Search

We have previously reported that sequence-controlled copolyesters such as poly((ethylene diglycolate) terephthalate) (poly(GEGT)) showed higher melting temperatures than those of the corresponding random copolymers and high biodegradability in seawater. In this study, to elucidate the effect of the diol component on their properties, a series of new sequence-controlled copolyesters composed of glycolic acid, 1,4-butanediol or 1,3-propanediol, and dicarboxylic acid units was studied. 1,4-Butylene diglycolate (GBG) and 1,3-trimethylene diglycolate (GPG) were prepared by the reactions of 1,4-dibromobutane or 1,3-dibromopropane with potassium glycolate, respectively. Polycondensation of GBG or GPG with various dicarboxylic acid chlorides produced a series of copolyesters. Terephthalic acid, 2,5-furandicarboxylic acid, and adipic acid were used as the dicarboxylic acid units. Among the copolyesters bearing terephthalate or 2,5-furandicarboxylate units, the melting temperatures (Tm) of the copolyesters containing 1,4-butanediol or 1,2-ethanediol units were substantially higher than those of the copolyester containing the 1,3-propanediol unit. Poly((1,4-butylene diglycolate) 2,5-furandicarboxylate) (poly(GBGF)) showed a Tm at 90 °C, while the corresponding random copolymer was reported to be amorphous. The glass-transition temperatures of the copolyesters decreased as the carbon number of the diol component increased. Poly(GBGF) was found to show higher biodegradability in seawater than that of poly(butylene 2,5-furandicarboxylate) (PBF). On the other hand, the hydrolysis of poly(GBGF) was suppressed in comparison with that of poly(glycolic acid). Thus, these sequence-controlled copolyesters have both improved biodegradability compared to PBF and lower hydrolyzability than PGA. [ABSTRACT FROM AUTHOR]

The enzymatic degradation of the recalcitrant poly(ethylene terephthalate) (PET) has been an important biotechnological goal. The present review focuses on the state of the art in enzymatic degradation of PET, and the challenges ahead. This review covers (i) enzymes acting on PET, (ii) protein improvements through selection or engineering, (iii) strategies to improve biocatalyst–polymer interaction and monomer yields. Finally, this review discusses critical points on PET degradation, and their related experimental aspects, that include the control of physicochemical parameters. The search for, and engineering of, PET hydrolases, have been widely studied to achieve this, and several examples are discussed here. Many enzymes, from various microbial sources, have been studied and engineered, but recently true PET hydrolases (PETases), active at moderate temperatures, were reported. For a circular economy process, terephtalic acid (TPA) production is critical. Some thermophilic cutinases and engineered PETases have been reported to release terephthalic acid in significant amounts. Some bottlenecks in enzyme performance are discussed, including enzyme activity, thermal stability, substrate accessibility, PET microstructures, high crystallinity, molecular mass, mass transfer, and efficient conversion into reusable fragments. [ABSTRACT FROM AUTHOR]

With the development of industrialization, the production scale and complexity of process industries are getting larger and larger. But, limited by the small amounts of samples and the uneven sample distribution in the process industry, it is difficult to establish accurate and efficient data-driven soft sensor models to predict some variables. To further develop the application of soft sensor models, generating new virtual samples based on the original sample distribution to extend the sample set is an ideal approach to solve this problem. In this paper, a novel virtual sample generation method based on the co-training of two K-Nearest Neighbor (KNN) models is proposed. First, according to the sparse parameter, sparse regions in each dimension of the feature space are identified. Second, the input features of virtual samples are generated in these sparse regions by performing interpolation operations. Third, the outputs of virtual samples are predicted by double KNN regressors based on co-training. The qualified virtual samples are screened and the model is updated using these virtual samples to improve the prediction accuracy of the double KNN models. To verify the effectiveness and superiority of the proposed virtual sample generation method based on the co-training (CTVSG), case studies are conducted using two standard functions and a Purified Terephthalic Acid (PTA) industrial dataset, where the effectiveness of CTVSG is confirmed. • A novel co-training based virtual sample generation method is proposed. • Sparse regions in each dimension on the feature space are identified. • The input features of virtual samples are generated by performing interpolation. • The outputs of virtual samples are predicted by double KNN based on Co-training. • The effectiveness of the proposed virtual sample generation method is conformed. [ABSTRACT FROM AUTHOR]

Large-scale terephthalic acid production from the oxidation of p-xylene is an especially important process in the polyester industry, as it is mainly used in polyethylene terephthalate (PET) manufacturing, a polymer that is widely used in fibers, films, and plastic products. This review presents and discusses catalytic advances and new trends in terephthalic acid production (since 2014), innovations in terephthalic acid purification processes, and simulations of reactors and reaction mechanisms. [ABSTRACT FROM AUTHOR]

Post-consumer polyethylene terephthalate (PET) plastic bottles, after some pre-processing, were chemically depolymerized for the production of terephthalic acid (TPA), an important monomer of PET resin. The optimized condition of PET hydrolysis was 100°C with 80% v/v aqueous sulfuric acid liquor for 30 min reaction time. The terephthalic acids (TPAs) were filtered out from the reaction mixtures with a sintered glass filter. The viscosity of recycled hydrolysis liquor was measured before it was used in a successive batch of PET depolymerization. The viscosity of hydrolysis liquor increased gradually from 5 mm2/s to 87 mm2/s. TPA yields were obtained from 85.03 ± 0.03% to 99.20 ± 0.06% and the color of TPA changed from bright white to off-white in the final batches. The structure of TPA was confirmed by FTIR, mass analysis, and 1H-NMR spectroscopy. The purity of TPA was found to be 95–98% from the HPLC study via external calibration technique. Thermogravimetric analysis (TGA) determined the thermal degradation patterns of TPAs and residual weights. This experiment reveals that repeated use of sulfuric acid hydrolysis liquor would be a good option for PET depolymerization in terms of resource utilization, TPA quality as well as sustainability. Graphical Abstract [ABSTRACT FROM AUTHOR]

Global warming and plastic pollution result from the massive use of fossil fuels, calling for the development of sustainable bioplastics derived from modern biomass. Bioplastic production is expected to increase to 2.43 million tons globally in 2024. In particular, the production of biopolymers from bioresources and organic waste should highly reduce waste accumulation. Biopolymers can be produced by employing microbes or by using monomers from agro-resources. Here we review the use of lignin and polylactic acid for polymer production using enzymes and microorganisms. Carnobacterium, Enterococcus and Aspergillus niger show high lactic acid productivity of about 0.4–1.4 g/L/h. Lignin and polylactic acid can also be transformed into value-added chemicals such as muconic acid, hydrouronic acid, adipic acid and terephthalic acid. [ABSTRACT FROM AUTHOR]

Three crystal complexes were designed and synthesised through the solvothermal method, with Cu2+, Zn2+, and Cd2+ ions as the metal centres and 2,4,6‐tri(2‐pyridyl)‐s‐triazine (TPTZ) and terephthalate (BDC2−) as the ligands. Their compositions were determined to be Cd(TPTZ)Cl2 (Cd‐MOF), {[Zn(TPTZ)(BDC)] ⋅ 3H2O}n (Zn‐MOF), and Cu2(PCA)2(BDC)(H2O)2 (Cu‐MOF) (PCA−=2‐pyridinium amide), respectively. Cd‐MOF can adsorb 90 % of Congo red (CR) in 10 s at room temperature and atmospheric pressure, and CR removal was complete at 20 s over a wide pH range. The adsorption capacity for CR reached 1440 mg g−1 in 5 min. Selective adsorption was demonstrated in mixed dyes. The adsorption kinetic data agree well with the pseudo‐second‐order kinetic model. The Temkin model was successfully used to evaluate the adsorption isotherms of CR on Cd‐MOF at room temperature, suggesting that adsorption occurs through a hybrid of monolayer and multilayer mechanisms. [ABSTRACT FROM AUTHOR]

Hydrolysis of protein samples into amino acids facilitates the use of NMR spectroscopy for protein and peptide quantification. Different conditions have been tested for quantifying aromatic amino acids and proteins. The pH-dependent signal shifts in the aromatic region of amino acid samples were examined. A pH of 12 was found to minimize signal overlap of the four aromatic amino acids. Several aromatic compounds, such as terephthalic acid, sulfoisophthalic acid, and benzene tricarboxylic acid, were applied as internal standards. The quantification of amino acids from an amino acid standard was performed. Using the first two suggested internal standards, recovery was ~97% for histidine, phenylalanine, and tyrosine at a concentration of approximately 1 mM in solution. Acidic hydrolysis of a certified reference material (CRM) of bovine serum albumin (BSA) and subsequent quantification of Phe and Tyr yielded recoveries of 98% ± 2% and 88% ± 4%, respectively, at a protein concentration of 16 g/L or 250 µM. [ABSTRACT FROM AUTHOR]

The fabrication of bio-based copolyester fiber with adjustable crystallization, orientation structure and mechanical property still remains a great challenge. In this study, a series of copolyester fibers based on terephthalic acid (PTA), ethylene glycol (EG) and l -Lactide (L-LA) were prepared via melt copolymerization and spinning. The resultant PLA- co -PET (PETLA) fibers exhibited tunable structure and property due to the synergistic effects of chemical structure and drawing process. The chemical structure of PETLA was confirmed by NMR, FTIR and XRD, which suggested that the random degree of copolymer increased with LA content and the viscosity decreased with the increase of LA content. The crystallization behavior, melting characteristic, thermal stability and rheological property were investigated by DSC, TGA and rheometer, the results indicated that all the PETLA exhibited the crystallization capacity, melting temperature and thermal stability were slightly affected by LA segment. The synergistic effects of LA segment and spinning process on PETLA structure and property were analyzed by WAXD and SAXS. The breaking strength of PETLA fibers dropped from 5.3 cN/dtex of PET to 2.8 cN/dtex of PET 85 LA 15 , which still met the requirements of most textile applications. Therefore, our work presented a feasible approach to prepare bio-based polyester fibers with tunable property. [ABSTRACT FROM AUTHOR]

A sorbent consisting of a lanthanum-loaded metal–organic framework, involving terephthalic acid (La@TPA) and amino terephthalic acid (La@ATPA) as organic linkers, was synthesized and evaluated for fluoride (F) removal from groundwater. F sorption on La@ATPA was unaffected by the initial pH and remained constant over pH 3–10. For a sorbent dose of 1.0 g L−1 in deionized water, the fluoride concentration decreased from 10 mg L−1 to 1.5 mg L−1 within 20 min with an F sorption capacity of 238 mg g−1. Besides, the fluoride removal rate remained unaffected by other anions as determined through binary sorption experiments. Leaching tests, including the toxicity characteristic leaching procedure (TCLP), revealed that an insignificant amount of fluoride (∼0.60 mg L−1) was released from the fluoride-loaded sorbent. F uptake primarily occurred due to the formation of LaF3(s), whose presence in fluoride-loaded La@ATPA was confirmed by transmission electron microscopy-selected area (electron) diffraction (TEM-SAED), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Besides, electrostatic and Lewis acid–base interactions were also suggested by Fourier-transform infrared spectroscopy (FTIR) and XPS analyses. Furthermore, the synthesized sorbent removed fluoride from 6.0 mg L−1 to 1.2 mg L−1 in groundwater within 90 min, with a relatively low dose of 2.5 g L−1. These results were consistent with the thermodynamic favorability of the formation of LaF3(s) over a wide range of conditions tested. The excessively high fluoride uptake, applicability to a broad pH range, recyclability, stability of the sorbed fluoride, and insignificant interference from common anions including those in fluoride-contaminated groundwater makes La@ATPA an attractive candidate for defluoridation. [ABSTRACT FROM AUTHOR]

Removal of 1,3-butadiene from cigarette smoke plays an important role in human health and environmental protection. Herein, a series of UiO-66 X% containing different ratios of the -NH2 group was synthesized via the solvothermal method by using terephthalic acid (H2BDC) and 2-aminoterephthalic acid (NH2-BDC) as ligands. Using GO as support, a series of UiO-66-NH2/GO Y% were prepared by controlling the ratio of UiO-66-NH2 and GO. The effects of -NH2 and GO contents on the structure and composition of MOFs were investigated. Finally, the different -NH2 contents of UiO-66 X% and the different GO contents of UiO-66-NH2/GO Y% were applied in 1,3-butadiene removal from cigarette smoke. The results showed that UiO-66 X% with the higher contents of -NH2 showed a higher rate of 1,3-butadiene removal, and UiO-66-NH2/GO Y% with the GO contents of 5% showed the highest removal rate of about 33.85%, which was 25.54% higher than that of activated carbon. In addition, the saturation capacity of the adsorbent materials for 1,3-butadiene was as high as 210.01–239.54 mg/g, showing great potential in reducing harmful components in cigarette smoke and environmental protection. [ABSTRACT FROM AUTHOR]

Waste polyester textiles are not recycled due to separation challenges and partial structural degradation during use and recycling. Chemical recycling of polyethylene terephthalate (PET) textiles through depolymerization can provide a feedstock of recycled monomers to make "as‐new" polymers. While enzymatic PET recycling is a more selective and more sustainable approach, methods in development, however, have thus far been limited to clean, high‐quality PET feedstocks, and require an energy‐intensive melt‐amorphization step ahead of enzymatic treatment. Here, high‐crystallinity PET in mixed PET/cotton textiles could be directly and selectively depolymerized to terephthalic acid (TPA) by using a commercial cutinase from Humicola insolens under moist‐solid reaction conditions, affording up to 30±2 % yield of TPA. The process was readily combined with cotton depolymerization through simultaneous or sequential application of the cellulase enzymes CTec2®, providing up to 83±4 % yield of glucose without any negative influence on the TPA yield. [ABSTRACT FROM AUTHOR]

• Environmental impact of the biorefinery varied with the allocation approach. • Technology maturity and byproduct valorization limit the use of economic allocation. • Oligosaccharides' price and byproduct valorization influence economic profitability. • Environmental prices reduced the environmental cost of fossil-based chemicals. • Ecotax and Ecovalue12 benefited the environmental cost of biobased chemicals. Sugar beet pulp, a byproduct from sugar beet refining, is used by farmers as fertilizer or sold as animal feed. Both options underestimate the potential of sugar beet pulp as a platform to produce specialty and bulky chemicals as a promising pathway for sustainable biochemicals – mind the pulp. This study proposes a biorefinery concept to produce food additives (pectin-derived oligosaccharides) and bulky chemicals (terephthalic acid). Since the biorefinery has a low technology readiness level (TRL = 1), it is relevant to evaluate the feasibility of this biorefinery concept to provide guidance (at an early stage) on the environmental and economic advantages and limitations. For this purpose, the life cycle assessment and techno-economic assessment frameworks are used to assess the environmental impact and economic performance of the biobased terephthalic acid, respectively. Moreover, environmental impacts are accounted for in economic terms using different monetary valuation methods (environmental prices, Ecovalue12, and Ecotax). The environmental impact of biobased terephthalic acid was higher in most impact categories than the fossil counterpart, depending on the selected allocation approach (mass vs economic). The economic feasibility of the proposed biorefinery is highly dependent on the pectin-derived oligosaccharides market price and the valorization of byproducts (humins and levulinic acid). The selection of the monetary valuation method is critical for monetizing environmental impacts when comparing biobased against fossil-based alternatives. [ABSTRACT FROM AUTHOR]

Sulfuric anhydrides, generated from the cycloaddition reaction of SO 3 with carboxylic acids, have been revealed to be potential participants in the nucleation process of new particle formation (NPF). Hence the reaction mechanisms of typical aromatic acids (benzoic acid (BA), phenylacetic acid (PAA), phthalic acid (PA), isophthalic acid (mPA), and terephthalic acid (PTA)) with SO 3 to generate the corresponding aromatic sulfuric anhydrides were investigated by density functional theory calculations at the level of M06-2X/6-311++G(3df,3pd). As a result, these reactions were found to be feasible in the gas phase with barriers of 0.34, 0.30, 0.18, 0.08 and 0.12 kcal/mol to generate corresponding aromatic sulfuric anhydrides, respectively. The thermodynamic stabilities of clusters containing aromatic sulfuric anhydrides and atmospheric nucleation precursors (sulfuric acid, ammonia and dimethylamine) were further analyzed to identify the potential role of aromatic sulfuric anhydrides in NPF. As the thermodynamic stability of a cluster depends on both the number and strength of hydrogen bonds, the greater stability of the interactions between atmospheric nucleation precursors and aromatic sulfuric anhydrides than with aromatic acids make aromatic sulfuric anhydrides potential participators in the nucleation process of NPF. Moreover, compared with BA, the addition of a -CH 2 - functional group in PAA has little influence on the reaction barrier with SO 3 but an inhibitive effect on the thermodynamic stability of clusters. The position of the two -COOH functional groups in PA, mPA and PTA does not have a consistent impact on the reaction barrier with SO 3 or the thermodynamic stability. [Display omitted] [ABSTRACT FROM AUTHOR]

Microplastics have become a ubiquitous contaminant in the environment. The present study focuses on the identification, characterization, and quantification techniques for tracking microplastics. Due to their unique compositional structure, unambiguous identification of individual polymers in various plastic samples, usually comprised of mixtures of individual polymers, remains a challenge. Therefore, there is limited research on the pyrolysis characterization of mixed samples. In this study, two analytical methods, TG-FTIR and TED-GC-MS combined with thermogravimetric analysis were used to evaluate the thermal-degradation process of individual and mixed samples of polypropylene (PP), polyethylene terephthalate (PET), and polyvinyl chloride (PVC). The primary interaction was the volatilization of terephthalic acid bound to chlorine molecules. The reduction of vinyl-ester functional groups and aromatic hydrocarbon intermediates related to olefin branching was confirmed. Char formation was increased, due to aromatic compounds from PET and PVC. All of the polymers used in the study may be underestimated in quantity, due to combined volatilizations during pyrolysis. TG-FTIR and TED-GC-MS showed forceful advantages in identifying mixed microplastics through different discrimination mechanisms. The study provides deep insight into pyrolysis behaviors and the interactions of mixed polymers, and the obtained results can help better comprehend the complex pyrolysis process. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is a prevalent synthetic polymer that is known to contaminate marine and terrestrial environments. Currently, only a limited number of PET-active microorganisms and enzymes (PETases) are known. This is in part linked to the lack of highly sensitive function-based screening assays for PET-active enzymes. Here, we report on the construction of a fluorescent biosensor based on Comamonas thiooxidans strain S23. C. thiooxidans S23 transports and metabolizes TPA, one of the main breakdown products of PET, using a specific tripartite tricarboxylate transporter (TTT) and various mono- and dioxygenases encoded in its genome in a conserved operon ranging from tphC-tphA1. TphR, an IclR-type transcriptional regulator is found upstream of the tphC-tphA1 cluster where TPA induces transcription of tphC-tphA1 up to 88-fold in exponentially growing cells. In the present study, we show that the C. thiooxidans S23 wild-type strain, carrying the sfGFP gene fused to the tphC promoter, senses TPA at concentrations as low as 10 mM. Moreover, a deletion mutant lacking the catabolic genes involved in TPA degradation thphA2-A1 (ΔtphA2A3BA1) is up to 10,000-fold more sensitive and detects TPA concentrations in the nanomolar range. This is, to our knowledge, the most sensitive reporter strain for TPA and we demonstrate that it can be used for the detection of enzymatic PET breakdown products. [ABSTRACT FROM AUTHOR]

A novel ion-mediated self-assembly method was applied for integration of graphene oxide (GO), propanoic- and glutaric-substituted perylenes (glu-PDI and PA-PDI), and Zn (OAc)2 into new hybrid materials with photocatalytic properties. The structuring of chromophores through coordination bonding on the GO surface is controlled by the chemistry of the PDI linkers. Four-substituted glu-PDI forms consolidated microporous particles, whereas di-substituted PA-PDI binds with GO into a macroporous gel-like structure. The GO/PDI controls without Zn2+ ions form only non-integrated dispersions. Both hybrids can initiate photodestruction of 1,5-dihydroxynaphtalene (DHN) due to the effective charge separation between the PDI components and GO by generating hydroxyl radicals determined by luminescent probing with terephthalic acid. The reduction mechanism of photodegradation was confirmed by MALDI-TOF spectroscopy. The structure of the hybrids controls the rate of photodegradation process. The glu-PDI-based photocatalyst shows a smaller rate of photoreduction of 3.3 × 10−2 min−1 than that with PA-PDA (4 × 10−2 min−1) due to diffusion limitations. Our results suggest that the ion-mediated synthesis is a useful and rational alternative for the conventional synthesis of GO-based functional hybrid materials through aromatic stacking between the graphene oxide and organic chromophores to produce new affordable and efficient photocatalysts. [ABSTRACT FROM AUTHOR]

Background: Over the 70 years since the introduction of plastic into everyday items, plastic waste has become an increasing problem. With over 360 million tonnes of plastics produced every year, solutions for plastic recycling and plastic waste reduction are sorely needed. Recently, multiple enzymes capable of degrading PET (polyethylene terephthalate) plastic have been identified and engineered. In particular, the enzymes PETase and MHETase from Ideonella sakaiensis depolymerize PET into the two building blocks used for its synthesis, ethylene glycol (EG) and terephthalic acid (TPA). Importantly, EG and TPA can be re-used for PET synthesis allowing complete and sustainable PET recycling. Results: In this study we used Saccharomyces cerevisiae, a species utilized widely in bioindustrial fermentation processes, as a platform to develop a whole-cell catalyst expressing the MHETase enzyme, which converts monohydroxyethyl terephthalate (MHET) into TPA and EG. We assessed six expression architectures and identified those resulting in efficient MHETase expression on the yeast cell surface. We show that the MHETase whole-cell catalyst has activity comparable to recombinant MHETase purified from Escherichia coli. Finally, we demonstrate that surface displayed MHETase is active across a range of pHs, temperatures, and for at least 12 days at room temperature. Conclusions: We demonstrate the feasibility of using S. cerevisiae as a platform for the expression and surface display of PET degrading enzymes and predict that the whole-cell catalyst will be a viable alternative to protein purification-based approaches for plastic degradation. [ABSTRACT FROM AUTHOR]

Is‐PETase has become an enzyme of significant interest due to its ability to catalyse the degradation of polyethylene terephthalate (PET) at mesophilic temperatures. We performed hybrid quantum mechanics and molecular mechanics (QM/MM) at the DSD‐PBEP86‐D3/ma‐def2‐TZVP/CHARMM27//rev‐PBE‐D3/dev2‐SVP/CHARMM level to calculate the energy profile for the degradation of a suitable PET model by this enzyme. Very low overall barriers are computed for serine protease‐type hydrolysis steps (as low as 34.1 kJ mol−1). Spontaneous deprotonation of the final product, terephthalic acid, with a high computed driving force indicates that product release could be rate limiting. [ABSTRACT FROM AUTHOR]

An attempt at the treatment of the waste fiber (WF) from the wind turbine blade (WTB) was made through the modifier of dopamine hydrochloride and the compound modifier of dopamine hydrochloride and 2,5-dihydroxy terephthalic acid or 3,4-dihydroxy cinnamic acid or 3,4-dihydroxy benzonitrile, corresponding to obtain four modified waste fibers (MWF1, MWF2, MWF3, and MWF4). The MWFs samples' microstructure properties were characterized using SEM, EDS, XPS, FTIR analyses, and water contact angle tests. The results revealed that all the MWF surfaces were wrapped by a distinct coating layer and had different elemental compositions and chemical groups, demonstrating the significant effect of the four modifications on the WF surfaces. The hydroxyl, amino, or nitrile groups were grafted onto the WF surfaces causing improvement of the hydrophilicity and reactivity. Furthermore, all the MWFs as the reinforced materials were incorporated into the industrial waste phosphogypsum (PG) to manufacture the phosphorous-building gypsum composites (PBGC). The effects on the micro-morphology and mechanical properties of the PBGC were evaluated. The results also show the improvement in flexural and compressive strength with the addition of MWFs into the PBGC, due to the enhancement of the compactness between the MWF and phosphogypsum matrix. In particular, the effects of three compound modifiers on the flexural and compressive strength are more significant. The highest flexural and compressive strength was contributed by the PBGC-MWF4 with 2% dosage using a compound modifier of dopamine hydrochloride and 3,4-dihydroxy benzonitrile, which were enhanced 61.04% and 25.97% compared with the PBG. [ABSTRACT FROM AUTHOR]

Summary: Flexible, lightweight, and freestanding zinc‐manganese oxide carbon nanofibers are promising materials for the fabrication of portable electronic devices. Composite nanofibers were synthesized using terephthalic acid and sodium dodecyl sulfate. Terephthalic acid improves the flexibility of the composite fibers and facilitates the diffusion of electrolytic ions. Meanwhile, sodium dodecyl sulfate aids to elevate the metal (zinc) oxide particles to the surface of the nanofibers during annealing. The texturing of the carbon nanofiber surface with ZnO enhances the electrochemical activity of the composite fibers. Parametric studies were conducted by varying the weight ratio of zinc and manganese acetates from zero to unity. The optimal case with a ratio of 0.75 produces specific capacitances of 1080 and 817 F·g−1 at current densities of 1 and 10 A·g−1, respectively, with a wide potential window of 1.6 V, indicating outstanding energy storage capabilities. The capacitance retention was 92% after 10 000 galvanostatic charge‐discharge cycles. The bending angle test confirmed the mechanical durability of the freestanding carbon nanofiber electrodes, and the corresponding change in the cyclic voltammetry curve was negligible. [ABSTRACT FROM AUTHOR]

Plastics and plasticizers accumulate in the ecological niches affecting biodiversity, and human and environmental health. Bacteria degrading polyethylene terephthalate (PET) were screened and PETases involved in PET degradation were characterized. Here, we identified a carboxylesterase Dkca1 of 48.44 kDa molecular mass from Dietzia kunjamensis IITR165 shown to degrade amorphous PET film into bis(2-hydroxyethyl) terephthalate (BHET) and terephthalic acid (TPA) formed 64.35 μM and 35.26 μM, respectively within 96 h at 37 °C as revealed by LC-MS analysis showed significant PET hydrolase activity similar to reported PETases. SEM analysis confirms the surface erosion as cavities and holes. Dkca1 also hydrolysed BHET and dibutyl phthalate (DBP) at a concentration of 1 mM within 3 h indicating its versatility. Fluorescence quenching shows Dkca1 protein has a maximum affinity (K d) towards BHET (86.55 μM) than DBP (134.2 μM). The protein demonstrated high stability under temperatures above 40 °C and at the pH range of 6.0–9.0. Moreover, Amino acid composition showed that the Dkca1 enzyme belongs to family VII carboxylesterase containing conserved catalytic triad of Ser183-Glu289-His378 with pentapeptide motif GXSAG and an oxyanion hole H103GGG106, sharing 37.47 % and 32.44 % similarity with a PET hydrolase TfCa from Thermobifida fusca and PAE hydrolase CarEW from Bacillus sp. K91, respectively. A docking study revealed that ligand PET, BHET, and DBP showed favourable binding in the catalytic pocket of the Dkca1 protein. • Dkca1 showed evolutionary significance of carboxylesterase from unknown genus like Dietzia. • Carboxylesterase, Dkca1 had catalytic triad of Ser183-Glu289-His378 sharing 37.47 % similarity. • Docking provided the possible molecular basis for carboxylesterase substrate specificity. [ABSTRACT FROM AUTHOR]

• Three ternary Cd(II)-CPs derived from new ligands were synthesized and characterized. • 1 − 3 are the first multi-responsive sensors for Cu2+, Hg2+, levofloxacin, and acetylacetone. • 1 − 3 demonstrated high sensitivity and selectivity in sensing these analytes. • The luminescent sensing mechanisms were discussed in detail. Employing coordination polymers (CPs) developing effective organic contaminants and heavy metal ions luminescent detection systems is an ongoing challenge. Three ternary Cd(II) CPs namely [Cd(MIP)(L) 0.5 (H 2 O)] n (1), [Cd 2 (TPA) 2 (L)(H 2 O)] n (2), and [Cd 2 (DCTP) 2 (L)(H 2 O)] n (3), (L = 1,6-bis(2-((1 H -imidazol-1-yl)methyl)-1 H -benzo[ d ]imidazol-1-yl)hexane, H 2 MIP = 5-methylisophthalic acid, H 2 TPA = terephthalic acid, and H 2 DCTP = 2,5-dichloroterephthalic acid) containing new L ligands, were hydrothermally synthesized and characterized. 1 displays a (4,4)-connected 4,4L28 layer and further extended into the 3D supramolecular framework via π − π stacking interactions. 2 exhibits a (4,4,5)-connected trinodal network with the point symbol of {42.5.62.8}{42.52.72}{42.53.62.73} 2. 3 takes on a (3,5,6)-connected framework with the point symbol {3.42.52.7}{3.82} 2 {33.44.5.62.82.92.10} 2. 1 − 3 show highly good thermal stability, and highly acid-base tolerance. The limits of detection (LOD) of 1 − 3 were calculated as follows: for Cu2+, the LODs are 8.92 × 10−8, 5.74 × 10−7, and 9.37 × 10−8 mol L−1, respectively; for Hg²⁺, the LOD values are 3.73 × 10−7, 5.22 × 10−7, and 8.45 × 10−7 mol L−1, respectively. Regarding levofloxacin (LEV), the LODs for 1 − 3 were found to be 5.11 × 10−8 mol L−1, 2.45 × 10−8 mol L−1, and 8.54 × 10−8 mol L−1, respectively. Finally, for acetylacetone (acac), the LODs of 1 − 3 are 5.53 × 10−6, 5.66 × 10−6, and 1.23 × 10−6 mol L−1, respectively. 1 − 3 represent the first examples of exceptional multi-responsive sensing platforms for the detecting of Cu2+, Hg2+, LEV, and acac with high sensitivity, outstanding anti-interference abilities, and low LODs. The possible sensing mechanisms were investigated in detail. Three new ternary Cd(II)-based coordination polymers were hydrothermally synthesized and characterized, which can act as exceptional multi-responsive sensing platforms for the detecting of Cu2+, Hg2+, levofloxacin, and acetylacetone with high sensitivity, outstanding anti-interference abilities, and low limit of detections. The possible sensing mechanisms were investigated in detail. [Display omitted] [ABSTRACT FROM AUTHOR]

Controlling the structure of metal-organic frameworks (MOFs) is a crucial strategy to enhance electrochemical performance. In this work, nanosheet-assembled hollow Ni-MOF spheres are synthesized by controlling the transition states through a facile trace water-assisted solvothermal method. During the research, it is found that water in the system, whether from the precursor Ni(NO 3) 2 ·6H 2 O or from an additional source, is a key influencing factor that can regulate the reaction process to control structural changes. Theoretical calculations prove that the water present in the reaction system can affect the distribution of terephthalic acid (TPA) and Ni2+, indicating that trace water can provide an accelerating effect. The nanosheet-assembled sphere shells can expose more active surface area, and the hollow structure can prevent the restacking of nanosheets and shorten the charge transport path. Based on these structural advantages, the prepared Ni-TPA MOF electrode achieves a high specific capacitance of 1010 F g−1 at 1 A g−1 and a 61 % rate capability at 20 A g−1. This work offers a feasible and highly effective strategy to design nanosheet-assembled hollow MOF spheres for high-performance supercapacitors and helps to understand the key factors influencing the formation of hollow MOF spheres. A small amount of water present in reaction system can show an accelerating effect for the formation of nanosheet-assembled hollow structure, where the obtained sample exhibits good electrochemical performance. [Display omitted] • A small amount of water present in reaction system can show an accelerating effect to prepare the hollow Ni-TPA MOFs. • The nanosheets as shells of Ni-TPA MOFs can expose the rich active sites. • The hollow structure can protect serious agglomeration of the nanosheets and reduce the transport path of electrolyte. • A good performance of 1010 F g−1 was obtained for the prepared Ni-TPA MOFs at 1 A g−1. [ABSTRACT FROM AUTHOR]

A terephthalic framework, Ni-BDC-NH 2 , was used to synthesize the nickel nanoparticles and nanoclusters on-site encapsulated within mesoporous carbon nanoflakes (NiO/Ni/CNF) for ammonia electrolysis. Ni2+ nodes recrystallized to form a core-shell oxide film covering the Ni metal, with the dispersity and particles size influenced by the pyrolysis temperature in a N 2 atmosphere. Electrochemical characterization and Raman spectra identified the solid-state Ni(II) ⇌ Ni(III) transition as the electron mediator, while its lowered onset potential (+1.3 V vs. RHE), compared to that of oxygen evolution reaction (+1.7 V) enhanced the Faradaic efficiency. The performance of electrodes in ammonia oxidation was assessed, which revealed a N 2 selectivity of at least 80 % under electrolytic conditions of current density = 0.5 – 1.5 mA cm−2, pH > 10, and initial NH 3 level = 50–300 mg-N L−1 using NiO/Ni/CNF(700). An undivided cell equipped with NiO/Ni/CNF(700) anode and Cu/Ni cathode was utilized to treat a real wastewater (∼500 mg-N L−1, pH 4.5). Consequently, both the removal efficiency of NH 3 and N 2 selectivity surpassed 90 % in a continuous flow mode for 4 days, indicating the durability of electrode system. [Display omitted] • Ni encapsulated within 2D mesoporous carbon nanoflakes was synthesized using Ni-MOF. • Pyrolysis temperature was critical to convert Ni2+ to core-shell NiO/Ni NPs or NCs. • NiO in reduced carbon substrate synergistically improved Faradaic efficiency. • NiO ⇌ NiOOH transition mediated NH 3 to N 2 or NO x depending on electrode potential. • Continuous-flow electrolysis of real wastewater validated the electrode stability. [ABSTRACT FROM AUTHOR]

Replacing fossil resource with biomass is one of the promising approaches to reduce our carbon footprint. Lignin is one of the three major components of lignocellulosic biomass, accounting for 10-35 wt% of dried weight of the biomass. Hydrogenolytic depolymerization of lignin is attracting increasing attention because of its capacity of utilizing lignin in its uncondensed form and compatibility with the biomass fractionation processes. Lignin is a natural aromatic polymer composed of a variety of monolignols associated with a series of lignin linkage motifs. Hydrogenolysis cleaves various ether bonds in lignin and releases phenolic monomers which can be further upgraded into valuable products, i.e. , drugs, terephthalic acid, phenol. This review provides an overview of the state-of-the-art advances of the reagent (lignin), products (hydrol lignin), mass balance, and mechanism of the lignin hydrogenolysis reaction. The chemical structure of lignin is reviewed associated with the free radical coupling of monolignols and the chemical reactions of lignin upon isolation processes. The reactions of lignin linkages upon hydrogenolysis are discussed. The components of hydrol lignin and the selectivity production of phenolic monomers are reviewed. Future challenges on hydrogenolysis of lignin are proposed. This article provides an overview of lignin hydrogenolysis reaction which shows light on the generation of optimized lignin ready for hydrogenolytic depolymerization. [Display omitted] [ABSTRACT FROM AUTHOR]

Rapid, sensitive and highly selective detection of nitro-aromatic explosives (NAEs) has become one of the most pressing environmental and safety issues. Metal-organic frameworks (MOFs) offer new possibilities for the development of new photoactive materials with excellent sensing properties. In this paper, three robust UiO-66-type fluorescent MOFs were prepared from the self-assembly of yttrium cations (Y3+) and linear dicarboxylic acid ligands, named terephthalic acid (BDC), 2-hydroxyterephthalic acid (OHBDC) and 2,5-dihydroxyterephthalic acid (DHBDC). The solid and solution fluorescence properties of three MOFs were successfully modulated by regulating the number of –OH functional groups from zero to two. At 370 nm excitation, Y-BDC MOF without –OH group was almost non-fluorescent, Y-OHBDC MOF with one –OH group emitted blue fluorescence, and Y-DHBDC MOF with two –OH groups emitted green fluorescence. Thanks to the suitable porous structures and stable frameworks, Y-OHBDC and Y-DHBDC MOFs both can quantificationally detect at least seven nitro-aromatic explosives (NAEs) by a fluorescence quenching process. Remarkably, the detection performance for 2,4,6-trinitrophenol (TNP) is the most outstanding with the K SV values of 8.4 × 104 M−1 and 2.1 × 105 M−1. Fast response, high sensitivity, strong anti-interference ability and good reusability make UiO-66-Y MOFs potential fluorescent sensors for TNP. Regulated by the –OH functional groups, the luminescent properties of three MOFs (Y-BDC, Y-OHBDC and Y-DHBDC) and the fluorescence sensing performance of Y-OHBDC and Y-DHBDC for more than seven nitro-aromatic explosives were systematically investigated. Y-OHBDC was found to have high degree of sensitivity, low LOD and excellent recoverability for explosives detection. [Display omitted] • Regulation on the ligand fluorescence in UiO-66-Y MOFs. • Fluorescence quenching. • Fast and sensitive detection of aromatic nitro explosives. [ABSTRACT FROM AUTHOR]

It is imperative to carry out more research on the proton conduction in metal-organic frameworks (MOFs) made of main group metals. Inspired by this, we synthesized a 3D indium-based MOF, [In(BDC-NH 3)(BDC-NH 2)]∙1.5DMF∙1.5H 2 O (namely In-MOF 1) , which is made up of [In(CO 2) 4 ] metal nodes and 2-amino terephthalic acid (H 2 BDC-NH 2) organic linkers. Meanwhile, organic ligand functionalization has been proven to be one of the effective techniques to boost the proton conductivity of the corresponding metal-organic frameworks. In light of this, the functionalized MOF was successfully synthesized using In(III) ions and H 2 BDC-NH 2 , which not only has excellent water stability but also bear some hydrophilic groups such as –NH 2 and carboxylate units, which may act as a pivotal role in improving the proton conductivity (σ). Consequently, the σ of In-MOF 1 was thoroughly examined. As expected, its optimal σ can reach 0.81 × 10−2 S cm−1 under 100 °C and 98 % relative humidity (RH), substantially higher than the In-MOF composed only of terephthalic acid. Finally, we estimated its activation energy (E a) at 98 % and 68 % RHs using the Arrhenius equation, and the proton transport mechanism was further explored. High intrinsic proton conduction in one three-dimensional indium(III)-organic framework built by amino terephthalic acidOne highly stable 3D In(III) MOF built by 2-amino terephthalic acid was synthesized, and its proton conductivity was explored fully. Moreover, its proton-conducting mechanism was deduced. [Display omitted] • One 3D In(III) MOF was prepared. > Amino terephthalic acid ligand was employed. > The MOF's proton-conductive properties were examined. > Its conducting mechanism was highlighted. >. [ABSTRACT FROM AUTHOR]

Two new Cd(II) metal-organic frameworks (MOFs) with the formula [Cd (TA) (L) (H 2 O)·DMF] n (1) and [Cd 3 (BTA) 2 (L) 2 (H 2 O) 4 (NO 3) 2 ] n (2) based on terephthalic acid (H 2 TA) and 2-bromoterephthalic acid (H 2 BTA) have been successfully synthesized using semi-rigid N-donor 3,5-di (1H-imidazole-1-yl)pyridine (L). The sensing results illustrated that both of them could be prospective candidates for developing luminescent sensors for the probing of Fe3+ and Cr 2 O 7 2−.The probe effects remained highly selective to the Fe3+ and Cr 2 O 7 2− ions even if there are other interfering ions. This may be attributed to the accessible open Lewis-base sites and uncoordinated pyridyl which make it simple to recognize diverse analytes. The detection limits for Fe3+, and Cr 2 O 7 2− are 4.459 ppm and 1.486 ppm respectively. At further optimized concentrations of Fe3+ and Cr 2 O 7 2−, the fluorescence "turn off-on" technique exhibits outstanding selectivity and sensitivity, and low detection limit for detecting 4-hydroxy acid and 2-hydroxy acid. Hirshfeld surfaces and fingerprint plots are extensively used to investigate intermolecular interactions, which play a crucial role in creating diverse supramolecular designs that can be compared. [Display omitted] • Synthesis of two new CPs using an auxiliary N-donor ligand. • 1 is a promising multi-responsive sensing material for detecting ions through fluorescence quenching (turn-off). • The sensing mechanism was explored in detail. [ABSTRACT FROM AUTHOR]

In this study, a series of low dielectric liquid crystal polyarylates were designed and synthesized through the acetylation of hydroxyl-containing monomers followed by melt polycondensation with 4-hydroxybenzoic acid (HBA), 6-hydroxy-2-naphthoic acid (HNA), bisphenol A (BPA), bisphenol AF (BPAF), terephthalic acid (TA) acid and 2,3,5,6-tetrafluoroterephthalic acid (TFTA). The molar ratio of HBA to HNA was controlled at 7:3. The structures of the acetylated monomers and polyarylates were characterized using FTIR and NMR spectroscopy, while the elemental composition of the polyarylates was analysed via XPS. WAXD and POM analyses revealed that the prepared polyarylates exhibit a single crystalline form and are capable of forming liquid crystals. DSC and TGA analyses indicated that the incorporation of bisphenol-type monomers (BPA or BPAF) disrupted the regularity of the main chain, leading to a decrease in both the melting point and thermal stability. Finally, the incorporation of bulky monomers (BPA or BPAF) and fluorinated monomers (BPAF and TFTA) into polyarylates increases free volume and decreases polarization, leading to a significant reduction in the dielectric constant. [Display omitted] • Low dielectric TLCPs were created via acetylation and polycondensation with different monomers for enhanced performance. • Advanced analysis methods confirmed successful synthesis and elemental composition, revealing liquid crystal capabilities. • Dielectric constant significantly reduced after introducing bulky and fluorinated monomers into TLCPs. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) is a widely used thermoplastic polymer in the packaging and materials industries, and is predicted to have continuous market growth in the future. Methods such as glycolysis and methanolysis of PET have been identified as promising approaches in sustainable chemical recycling of PET. The latter produces dimethyl terephthalate (DMT), which can be easily hydrolyzed to terephthalic acid (TPA) at elevated temperatures and pressures, and further reused for PET production. The aim of this study was to develop a kinetic model for the hydrolysis of dimethyl terephthalate, using the experimental data. Various reaction conditions (temperature, pressure, time) have been investigated and used to calculate the activation energies and reaction rate constants, while the variation in reactor setup with methanol (MeOH) removal was conducted to show its detrimental effect on the efficiency of the reaction and selectivity towards terephthalic acid. The first reaction step of DMT to monomethyl terephthalate (MMT) is relatively irreversible, while the second reaction step of MMT to TPA ceases, as soon as the equilibrium is reached. Highest yields of TPA (76.7 %) were obtained after 40 min at 265 °C, with MeOH removal, and the activation energy was calculated to be 95 and 64 kJ mol−1 for the first and second hydrolysis reaction step, respectively. [Display omitted] • Kinetics of dimethyl terephthalate (DMT) hydrolysis during reactive distillation. • Reversible reaction between monomethyl terephthalate (MMT) and terephthalic acid (TPA). • The removal of methanol (MeOH) from the reaction mixture improves the final TPA yield. • Carbon balance loss is attributed to unavoidable sublimation of TPA during reactive distillation. [ABSTRACT FROM AUTHOR]

The increasing demand for plastic has resulted in a surge in plastic waste production. Polyethylene terephthalate (PET), commonly used in beverage bottle manufacturing, is only partially recycled, with an estimated recycling rate of just 28.4% in 2019. This accumulation of plastic waste is harmful to the environment and living organisms, necessitating effective recycling methods for PET waste. One promising method is alkaline hydrolysis using NaOH, which can break down PET into its monomer components, terephthalic acid (TPA) and ethylene glycol (EG). This process not only recycles PET efficiently but also manages contaminants effectively, producing high-quality TPA, supporting the development of a circular economy. This study looks into PET depolymerization via alkaline hydrolysis at low temperature by investigating effects of various factors: pH levels, water to ethanol ratio, NaOH concentration, NaOH to PET ratio, reaction time, PET size, reusability of unreacted PET, air plasma pretreatment of PET, and different kinds of PET. Promisingly, PET conversion rates of over 90% and a TPA purity of 99.6% were achieved in this study highlighting the efficacy of alkaline hydrolysis in depolymerizing post-consumer PET waste. Ultimately, this research advances sustainable plastic waste management and supports the integration of PET into a circular economy framework. [Display omitted] • Achieved ∼90 % PET conversion from bottle waste with NaOH:PET molar ratio of 2.2. • Reduced use of acidifying agents due to lower NaOH, resulting in less wastewater. • Lower reaction conditions: temperature of 82 °C and reaction time of 30 min. • Obtained nearly 98.4% TPA yield with a purity of about 99.6%. • Cascade depolymerization technique enhanced PET conversion within same timeframe. [ABSTRACT FROM AUTHOR]

[Display omitted] • Accelerating terephthalic acid formation is achieved in a hydrothermal semi-batch setup. • TPA is the main component mobilized in the flow-through water, oligomer products can be withheld in the hydrothermal system. • Approximative reactor signal deconvolution shows that the reaction is not solubility limited. This research delves into the hydrothermal decomposition of PET [poly(ethylene terephthalate)] between 523 and 573 K temperature at 10 MPa pressure. PET was placed in a packed column, and a constant water flow was maintained with an average residence time of water between 403 and 430 s as it travelled from the reactor to the end of the system. Terephthalic acid (TPA) recovery ranged from 87 % to 94 %, increasing with the temperature. The time of full conversion of the 0.5 g PET by 1 g/min water flow rate reduced from 2500 to 1200 sec, with increasing temperature. To prevent premature precipitation of TPA during cooling, an alkaline quench stream was employed. Terephthalic acid isolation involved acidification-driven precipitation and subsequent filtration at atmospheric pressure. The solid dry TPA product underwent NMR analysis, showing structural conformity and DSC/TGA measurement, which presented a purity of 99.5 w/w%. The fractional end-of-pipe sampling showed accelerating reaction rates at each temperature, which supports the autocatalytic nature of hydrothermal disintegration of the PET. Using the determined residence time distribution in the system, from the end-of-pipe data a crude Fourier transform-based backward calculation was carried out to map the variation of the TPA concentration in the high-temperature and −pressure reactor. [ABSTRACT FROM AUTHOR]

2,5-furandicarboxylic acid is an extremely appealing renewable chemical building block because of its potential to replace the petrochemical and industrially widespread terephthalic acid via the synthesis of poly(alkylene 2,5-furanoate)s (2,5-PAF). The recent interest in its structural isomer, 2,4-furandicarboxylic acid (2,4-FDCA), opened the study of poly(alkylene 2,4-furanoate)s (2,4-PAF). In this work, 2,4-FDCA was polymerized with linear glycols of increasing chain length, via a solvent-free polycondensation reaction, obtaining high molecular weight 2,4-PAF. Namely, poly(trimethylene 2,4-furanoate) (2,4-PTF), poly(pentamethylene 2,4-furanoate) (2,4-PPeF) and poly(hexamethylene 2,4-furanoate) (2,4-PHF). These polyesters were compression molded into films and subjected to NMR, GPC, WAXS, PLOM, TGA and DSC analyses. The functional properties for food packaging applications were evaluated by mechanical and gas permeability tests. 2,4-PAF had tunable mechanical properties, depending on the glycol used, and in some cases, the mechanical behavior of a thermoplastic elastomer and shape recovery after break. In particular, 2,4-PPeF had outstanding gas barrier properties, while DSC analyses on 2,4-PHF showed an endothermic phenomenon attributed to the isotropization of a partially-ordered phase: it was possible to demonstrate that this phase was disrupted during tensile tests and slowly recovered over time, at room temperature. Overall, the results offer new insights into the structure-property relationships of poly(alkylene 2,4-furanoate)s and display their great potential for the production of biobased, monomaterial, easily recyclable and sustainable food packaging. [Display omitted] • Green synthesis of high molecular weight 2,4-FDCA-based polyesters. • Functional properties suitable for sustainable food packaging. • Isomerism-properties relationship. [ABSTRACT FROM AUTHOR]

Based on this research, we anticipate that higher solubility and high permeability in molecular adducts will aid in the development of novel BIL formulations. [Display omitted] • Bilastine (BIL) is a novel 2nd generation antihistamine medication used to treat symptoms of chronic urticaria and allergic rhinitis. However, its poor solubility limits its therapeutic effectiveness. • To enhance the physicochemical characteristics of BIL, various molecular adducts of BIL with Terephthalic acid (TA), 2,4-Dihydroxybenzoic acid (2,4-DHBA), Vanillic Acid (VA), Hydroquinone (HQN), and Hippuric acid (HA) were prepared. • All of the molecular adducts were crystallized using liquid-assisted grinding (LAG) followed by crystallization. • Single-crystal X-ray diffraction (SCXRD) studies avowed that the architectures of the molecular adducts are maintained in the solid state by strong (N+-H···O-, N-H ···O, O-H···O) and weak (C-H···O) hydrogen bonds. • Powder X-ray diffraction (PXRD) was used to validate the bulk phase purity of novel solid forms, and thermal analytical methods were used to further analyse the thermal stability of those forms. • The post-solubility PXRD analysis demonstrated that the majority of the molecular adducts were stable and did not experience any phase shift or dissociation. Bilastine (BIL) is a novel 2nd generation antihistamine medication is used to treat symptoms of chronic urticaria and allergic rhinitis. However, its poor solubility limits its therapeutic efficacy. In order to enhance the physicochemical characteristics of BIL, various molecular adducts of BIL (Salt, hydrate and co-crystal) were discovered in this study using two distinct salt-formers: Terephthalic acid (TA), 2,4-Dihydroxybenzoic acid (2,4-DHBA), and three nutraceuticals (Vanillic Acid (VA), Hydroquinone (HQN) and Hippuric acid (HA)). Various analytical methods were used to examine the synthesised adducts, including Powder X-Ray Diffraction (PXRD), Single Crystal X-ray Diffraction (SCXRD), and thermal analysis (Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC)). Single-crystal X-ray diffraction (SCXRD) studies avowed that the architectures of the molecular adducts are maintained in the solid state by an array of strong (N+ H⋯O−, N H⋯O, O H⋯O) and weak (C H⋯O) hydrogen bonds. Additionally, a solubility test was performed to establish the in vitro release characteristics of newly synthesised BIL adducts and it observed that most of the molecular adducts exhibit higher rates of dissolution in comparison to pure BIL; in particular, BIL.TA.HYD showed the highest solubility and the fastest rate of dissolution. Moreover, experiments on flux permeability and diffusion demonstrated that the BIL.TA.HYD and BIL.VA salts had strong permeability and a high diffusion rate. In addition, the synthesized adduct's stability was assessed at 25 °C and 90 % ± 5 % relative humidity, and it was found that all the molecular salts were stable and did not undergo any phase changes or dissociation. The foregoing result leads us to believe that the newly synthesized molecular adducts' increased permeability and solubility will be advantageous for the creation of novel BIL formulations. [ABSTRACT FROM AUTHOR]

The technical and economic viability of producing fully bio-based polyethylene terephthalate (PET) or its monomers was investigated. First generation (1 G) biorefineries, utilizing A-molasses, and combined first and second generation (1G2G) biorefineries, utilizing molasses and sugarcane bagasse and brown leaves, were considered. Simulations were developed for self-sufficient biorefineries, where the energy demands were met by utilizing the existing sugar mill boiler, accompanied by a new medium-pressure boiler and biogas generator. 1G2G scenarios required the replacement of the sugar mill boiler with a new, high-efficiency combined heat and power (CHP) plant, where electricity and useful heat were generated from a portion of 2 G biomass and other residues. 1 G PET was unprofitable at a minimum selling price (MSP) of $2946.t−1. 1 G production of Ethylene ($1847.t−1), monoethylene glycol (MEG) ($1648.t−1), 5-Hydroxymethylfurfural (HMF) ($1576.t−1) and iso-butanol (iButOH) ($1292.t−1) were more economically viable than PET, terephthalic acid (TPA) ($2689.t−1) and p-xylene (PX) ($2983.t−1), due to less complex processing and lower energy demands. 1G2G biorefineries were less profitable than 1 G equivalents, due to the cost of pretreatment and new CHP plants. The most profitable scenario was 1 G iButOH, with an MSP 19.0 % lower than its market price. New technologies to produce p-xylene and TPA from biomass in fewer steps, such as Virent Inc.'s Bioforming® technology, could potentially improve the economic viability of PET in the future. • Biobased PET, monomers and precursors were studied. • Simulations were developed and TEAs were performed for 1 G and 1 G2G scenarios. • PET is not profitable due to high cost and energy demand of p-xylene production. • Ethylene, iButOH, MEG and HMF are more viable than PET. • 1G Iso-butanol was the most profitable scenario. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of nanorod TiO 2 @NH 2 -BDC MOF composite using hydrothermal method. • NH 2 -MIL-125@TiO 2 composite sensors exhibited selectivity towards ammonia detection. • NH 2 -MIL-125@TiO 2 demonstrated improved sensor response to ammonia at 50 ppm. • All materials are able to detect NH 3 , HCHO and CH 3 COOH at 1 ppm concentration. • Sensor behavior is explained based on enhanced surface activity, formation of oxygen depletion layer. Herein, we have developed a highly sensitive chemiresistive TiO 2 doped metal–organic framework(MOF) composite-based sensor for ammonia detection at room temperature. Two novel Ti-MOFs@TiO 2 composites are developed employing terephthalic acid and 2-amino terephthalic acid as organic linkers with Titanium tetra isopropoxide (TTIP) as a metal source by solvothermal technique. The morphology and crystallinity of synthesized compounds were characterized by using Field-emission scanning electron microscopy (FE-SEM) with EDX analysis, X-ray diffraction (PXRD), XPS and Brunauer–Emmett–Teller (BET) analysis techniques. MIL-125@TiO 2 sensors exhibited a more specific surface area (374.74 m2 g−1) than the other three compounds. For gas-sensing applications, all composite materials were exposed to different gas vapours like ammonia, formaldehyde, acetic acid, ethyl alcohol, acetone, xylene, toluene and benzene at room temperature. The sensing results indicate that the sensors exhibit excellent response at low concentrations of ammonia, formaldehyde and acetic acid gases (1 ppm level). The enhanced sensor response was attributed to MIL-125@TiO 2 (85 response at 50 ppm) and NH 2 -MIL-125@TiO 2 (71 response at 50 ppm) towards ammonia gas and shows a better selectivity, sensitivity and repeatability to ammonia gas. All the materials exhibited less response times (between 8 and 45 sec) and more recovery times (between 13 and 125 sec). [ABSTRACT FROM AUTHOR]

The bismuth-rich strategy, which involves increasing the bismuth content within the BiOCl structure, offers an effective approach for tailoring the physicochemical and optoelectrical properties of BiOCl photocatalysts for enhanced photocatalytic performance. In this study, BiOCl, Bi 12 O 15 Cl 6 , and Bi 12 O 17 Cl 2 were selectively synthesized using the ethylene glycol (EG)-assisted microwave irradiation method by regulating the pH of the reaction solution. Photocatalytic performance was evaluated by studying bisphenol A (BPA) degradation and arsenite (As(III)) oxidation under visible-light irradiation. The energy structures and bandgaps of the materials were tuned according to their chemical compositions, affecting their photocatalytic activity. Bi 12 O 17 Cl 2 (EG-pH 9) exhibited superior photo-efficiency: 85.4 % of BPA and 97.6 % of As(III) were removed by Bi 12 O 17 Cl 2 (EG-pH 9) at rates 17.7 and 18.4 times higher than those of BiOCl (EG-initial pH 3), respectively. This superior performance attributed to the synergistic effect between the bismuth-rich nature and oxygen vacancies (OVs) induced by EG, along with the presence of OH− ions in the reaction solution. The increased number of OVs in Bi 12 O 17 Cl 2 led to enhanced photocurrent density and charge transfer efficiency. Trapping experiments, DMPO-ESR spin-trapping, nitroblue tetrazolium transformation, terephthalic acid photoluminescence probing, and o -tolidine oxidation experiments identified holes (h+), superoxide radicals (•O 2 −), superoxide radicals (•OH) and electrons (e−) as the reactive species. Density functional theory calculations further highlight the OV of Bi 12 O 17 Cl 2 as the active site for O 2 adsorption. This study not only developed an effective method for fabricating bismuth-rich oxychlorides with OVs but also demonstrated the potential of these photocatalysts for wastewater treatment. [Display omitted] • A series of bismuth oxychlorides was prepared using a microwave irradiation method. • Ethylene glycol and pH had impacted composition control and OVs formation. • Bi 12 O 17 Cl 2 showed excellent photocatalytic removal of BPA and As(III). • Enhanced photoactivity ascribed to high Bi content, rich OVs, and larger surface area. • Photocatalytic mechanisms were comprehensively studied. [ABSTRACT FROM AUTHOR]

In conjunction with the extensive production and widespread utilization of polyethylene terephthalate (PET) plastics, the issue of environmental pollution resulting from PET product disposal has gained increasing prominence. Consequently, researchers have been focusing on the development of cost-effective, sustainable, environmentally friendly, and efficient methodologies for recycling waste PET plastics and converting them into value-added products. PET, being a polymer with a high carbon content, serves as an exemplary carbon source for various carbon materials, encompassing porous carbon materials and carbon dots. Hence, it is imperative to design and develop carbon materials with solid functionality and wide-ranging applications utilizing waste PET. Additionally, PET can be depolymerized to produce terephthalic acid (TPA), which finds extensive application as an organic ligand for synthesizing metal-organic frameworks materials (MOFs). Consequently, low-cost waste PET is regarded as an optimal precursor for the large-scale preparation of MOFs. Converting waste PET into MOFs presents a novel strategy for chemical recycling. This review presents the recent advancements in functional upcycling and high value-added conversion of waste PET plastics, such as carbon materials, MOFs, aerogel and hydrogel. It comprehensively outlines the preparation methods for diverse categories of porous carbon materials and MOFs, emphasizing their applications in adsorption, energy storage, and catalysis, while also proposing future research directions pertaining to waste PET plastics. [Display omitted] • A review of various activation methods for converting PET into carbon materials. • Different synthesis methods for waste PET-based MOFs were summarized. • Outlines the specific applications of waste PET-based carbon materials in different fields. • Waste PET-based MOFs were categorized in various fields of application. • Potential future applications of waste PET-based carbon materials and MOFs were proposed. [ABSTRACT FROM AUTHOR]

2,5-Furanedicarboxylic acid (FDCA) is a valuable compound with the potential as a renewable and green alternative to terephthalic acid in polyester production. To address the issues of flammability, explosiveness, and product separation challenges associated with the current aerobic oxidation of 5-hydroxymethylfurfural (5-HMF) to FDCA route, herein, for the first time, a one-pot four-step direct reaction pathway for the synthesis of FDCA from 2,5-diformylfuran (DFF) and hydroxylamine salt is proposed. Under optimized conditions of 120 ℃ for 8 h, [HSO 3 -b-mim]·CF 3 SO 3 catalyst and p-xylene-water dual liquid phase solvent, 100 % DFF conversion and 91.0 % FDCA separation yield were obtained. Notably, [HSO 3 -b-mim]·CF 3 SO 3 exhibited excellent stability, maintaining its activity after being recycled more than five times. Through online experimentation and density functional theory (DFT) calculations, a four-step reaction mechanism involving aldehyde oximation, oxime dehydration, nitrile hydrolysis, and amide hydrolysis was proposed. This reaction pathway offers significant industrial application value due to its high FDCA yield, simple product separation, easy recovery and recycling of ionic liquid, and elimination of the need for oxygen. [Display omitted] • A completely new 2,5-Furanedicarboxylic acid synthesis pathway was constructed. • 2,5-furandicarboxylic acid was prepared from 2,5-diformylfuran without O 2. • The separation yield of 2,5-furanedicarboxylic acid was as high as 91.0 %. • [HSO 3 -b-mim]·CF 3 SO 3 retained high catalytic activity after 5 consecutive cycles. • The plausible reaction mechanism was proposed based on DFT calculations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The probes were prepared by integrating the dual-enzyme catalytic activity of CuO NPs and luminescent of Ln ICPs via facile self-assembly. • The self-cascade nanoenzyme activity of CuO nanoparticles was significantly enhanced upon encapsulated into Ln ICPs. • A versatile ratiometric platform for ultrahigh selective and sensitive detection of GSH was established. Tandem enzyme can catalyze some cascade reactions with high efficiency, and some few tandem enzyme-like mimics have been discovered recently. Further improving the catalytic efficiency of tandem nanoenzymes with facile method may undoubtedly promote and broaden their applications in various fields. In this work, cupric oxide nanoparticles (CuO NPs) with dual-functional enzyme mimics were synthesized using the rapid deposition method in advance, which simultaneously combined with lanthanide infinite coordination polymers (Ln ICPs) during the self-assemble of Tb3+, guanine-5′-triphosphate (GTP) and auxiliary ligand terephthalic acid (TA). Excitingly, the obtained Tb-GTP/TA@CuO ICPs, not only displayed obviously enhanced tandem catalytic activity compared with pure CuO NPs, but also provided a versatile ratiometric platform for ultrahigh selective and sensitive detection of glutathione (GSH) under single-wavelength excitation. A good linear relationship between the ratio signal and the GSH concentration was spanning from 0.001 to 20 μM with an impressive detection limit of 0.50 nM. This study opens a new and universal avenue for preparing integrated multifunctional probes by coupling of nanoenzyme catalytic activity with superior luminescent Ln ICPs through facile method. [ABSTRACT FROM AUTHOR]

• A fungus Papiliotrema laurentii S2P4P with the capability of simultaneous degradation of PLA and PBAT was isolated from an agricultural field. • S2P4P decreased the half-life of PLA/PBAT blends from approximately 3 years to 138 days. • PLA/PBAT blends were degraded to their monomers or oligomers by S2P4P. Polylactic acid/polybutylene adipate- co -terephthalate blend (PLA/PBAT) has been widely used due to their good biodegradation. Recently, the biodegradation of PLA and PBAT has received increasing attention. However, PLA/PBAT blend-degrading strains have been rarely reported in comparison to that for pure PLA and PBAT. A fungus strain, Papiliotrema laurentii S2P4P, was isolated from agricultural soils and identified. S2P4P can efficiently degrade commercial PLA/PBAT films at 30°C in mineral salt medium (MSM) and obtained about 14% of weight loss within 30 days of incubation. Additionally, rough and uneven surface of PLA/PBAT film with cracks and creases, increased hydrophilicity, changes in mechanical property, and decreased intensity of C=O and C-O bonds were observed after S2P4P treatments. The strain secreted esterase to catalyze the degradation of the ester bonds in PLA/PBAT blend, resulting in the production of degradation products such as butanediol, adipic acid, lactic acid and terephthalic acid as well as their oligomers. Furthermore, as carbon and energy sources, the degradation products could participate in the metabolism of S2P4P and then accelerate degradation of PLA/PBAT blend. The advantages of P. laurentii S2P4P in simultaneous degradation of PLA and PBAT indicated that the strain has potential value for the bioremediation of PLA/PBAT blend in the actual environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Renewable chemicals produced from sustainable sources, such as lignocellulosic biomass, are gaining significance as viable alternatives for chemicals conventionally produced from fossil fuels. This shift aims to improve the sustainability of the chemical and petrochemical industries. Polyethylene terephthalate (PET), widely used in our daily lives, is typically produced by co-polymerising ethylene glycol (EG) with dimethyl terephthalate (DMT) or terephthalic acid (TPA). This review compares the catalytic production of PET co-monomers using biomass feedstock with fossil-fuel-based production processes. The biomass-based pathways for EG, DMT, and TPA are not as competitive as conventional fossil-fuel-based routes owing to their high feedstock prices. Although commercial processes for the direct conversion of biomass into EG, DMT, and TPA are not yet available, promising catalytic routes are emerging. Continued technological advancements in the renewable production of PET monomers are expected to render bio-based PET economically feasible soon. [Display omitted] • PET is made from terephthalic acid or dimethyl terephthalate with ethylene glycol. • The three monomers of PET can be derived from biomass feedstocks. • Ethylene glycol is made mainly from cellulose in biomass. • Terephthalic acid is made mainly from hemicellulose or lignin in biomass. • Dimethyl terephthalate production from biomass has relatively rarely been studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mole balance and process stability validate the reliability of the CRU. • Maximum reactor productivity of 356 g TPA h−1 L-1 was achieved at 310 °C. • nHTP solid products contain close to 80 % of the carbon present in PET. • Repolymerization of nHTP250°C solids delivered rPET similar to commercial PET. • Technical feasibility of PET closed-loop recycling based on nHTP was demonstrated. Plastics have undeniably played a crucial role in the technological and societal advancements over the past decades. However, the current linear consumption model and the reliance of the plastic industry on fossil carbon pose pressing environmental and economic challenges that cannot be ignored. In this context, poly(ethylene terephthalate) (PET) has emerged as one of the most studied plastics in the field of chemical recycling, given its extensive use in packaging and textiles, and its susceptibility to undergo solvolysis into its constituent monomers, which facilitates closed-loop recycling of PET waste. This study presents the validation of a first-of-its-kind continuous flow system that utilizes subcritical water for neutral hydrothermal processing of PET at three different reaction temperatures 250, 280 and 310 °C. Regardless of the processing conditions, PET underwent full conversion into monomers and low molecular weight esters like mono(2-hydroxyethyl) terephthalate (MHET) and bis(2-hydroxyethyl) terephthalate (BHET), with an approximate carbon distribution of 20 % and 80 % between aqueous and solid products, respectively. The product composition is strongly related to the processing conditions, with 77.5 % ethylene glycol and 94.2 % terephthalic acid recovered as monomers at 310 °C. Furthermore, solid products were repolymerized to assess the potential of reusing the heterogeneous precursor mixture as starting material for PET production. Results reveal that the solid products obtained at 250 °C yielded polymer chains with decomposition temperature, melting temperature, crystallinity, and average molecular weight (50.4 kDa) closest to commercial PET. These results underscore the potential of neutral hydrothermal processing in a future circular PET value chain. [ABSTRACT FROM AUTHOR]

Abstract Three crystal complexes were designed and synthesised through the solvothermal method, with Cu2+, Zn2+, and Cd2+ ions as the metal centres and 2,4,6‐tri(2‐pyridyl)‐s‐triazine (TPTZ) and terephthalate (BDC2−) as the ligands. Their compositions were determined to be Cd(TPTZ)Cl2 (Cd‐MOF), {[Zn(TPTZ)(BDC)] ⋅ 3H2O}n (Zn‐MOF), and Cu2(PCA)2(BDC)(H2O)2 (Cu‐MOF) (PCA−=2‐pyridinium amide), respectively. Cd‐MOF can adsorb 90 % of Congo red (CR) in 10 s at room temperature and atmospheric pressure, and CR removal was complete at 20 s over a wide pH range. The adsorption capacity for CR reached 1440 mg g−1 in 5 min. Selective adsorption was demonstrated in mixed dyes. The adsorption kinetic data agree well with the pseudo‐second‐order kinetic model. The Temkin model was successfully used to evaluate the adsorption isotherms of CR on Cd‐MOF at room temperature, suggesting that adsorption occurs through a hybrid of monolayer and multilayer mechanisms.

To manage the polycotton textile-waste fabric (PCWF), a modified alkaline hydrolysis method is used for decolorization and separation of polyester as terephthalic acid (TPA). The effects of optimum conditions on TPA yield (%) have been determined to be 97.66 ± 1.94 %. Dye degradations and K/S values are measured by UV-visible spectrophotometer. K/S value of PCWF is 37.06 and separated cotton fabric (SCF) is 0.035, respectively. The chemical functionalities and crystallinity of PCWF, SCF, and TPA are determined by using FTIR and XRD. FTIR peak values are 1684 cm-1, 1574 cm-1, 1512 cm-1, 1280 cm-1, and 1425 cm-1 that prove transformation of polyester to TPA. XRD peaks confirm polyester conversion to TPA, and the values are 17.4, 25.13, 28.12, 29.09, and 38.7. TGA, SEM, and EDX data showed the thermal stability, morphology, and elemental composition of TPA. [ABSTRACT FROM AUTHOR]

Automobile exhaust gases, plastic pollutants, smoking, and other harmful substances can cause serious harm to human beings and the environment. Styrene, as a common airborne toxin, enters the human body through breathing or the skin and is discharged in the form of phenylglyoxylic acid (PGA). Therefore, specific, sensitive and trace detection of PGA is particularly important. Here, two zinc-based metal–organic frameworks {[Zn2L1(DMF)2H2O](DMF)2H2O}n, {[Zn4(L2)2(DMF)2(H2O)3](DMF)8}n (L1 = 2,5-bis((3-carboxylphenyl)amino)terephthalic acid, L2 = 2,5-bis((4-carboxyphenyl)amino)terephthalic acid) have been reported as 1 and 2, respectively. Both 1 and 2 present 3D structures, which can both be simplified as 4,4,4-c net topology. It is worth mentioning that 2 has two different kinds of Zn SBUs as connecting nodes in the structure. Besides, compared with the other materials for the detection of PGA, 1 and 2 exhibit relatively low detection limits (LODs), both in water and in urine (where the LODs for 1 in water and urine were 0.33 μM and 0.43 μM in the range of 0–0.39 mM, and those for 2 were 0.28 μM and 0.49 μM in the range of 0–0.59 mM, respectively). In addition, the sensors have excellent anti-interference ability, high stability, rapid response, and can easily distinguish between different concentrations of PGA with the naked eye. The developed paper probes were suitable for practical sensing applications for portable detection of PGA in urine. [ABSTRACT FROM AUTHOR]

Public health concerns associated with the potential leaching of substances from Polyethylene terephthalate (PET) packaging have been raised due to the role of phthalates as endocrine-disrupting chemicals or obesogens. In particular, changes in the environment such as pH, temperature, and irradiation can improve contaminant migration from PET food packaging. In this study, the in vitro effects of p-phthalates terephthalic acid (TPA) and dimethyl terephthalate (DMT) on murine adipocytes (3T3-L1) were evaluated using concentrations that might be obtained in adult humans exposed to contaminated sources. TPA and, in particular, DMT exposure during 3T3-L1 differentiation increased the cellular lipid content and induced adipogenic markers PPAR-γ, C/EBPß, FABP4, and FASN, starting from low nanomolar concentrations. Interestingly, the adipogenic action of TPA- and DMT-induced PPAR-γ was reverted by ICI 182,780, a specific antagonist of the estrogen receptor. Furthermore, TPA and DMT affected adipocytes' thermogenic program, reducing pAMPK and PGC-1α levels, and induced the NF-κB proinflammatory pathway. Given the observed effects of biologically relevant chronic concentrations of these p-phthalates and taking into account humans' close and constant contact with plastics, it seems appropriate that ascertaining safe levels of TPA and DMT exposure is considered a high priority. [ABSTRACT FROM AUTHOR]

Several microorganisms have been reported as capable of acting on poly(ethylene terephthalate) (PET) to some extent, such as Yarrowia lipolytica, which is a yeast known to produce various hydrolases of industrial interest. The present work aims to evaluate PET depolymerization by Y. lipolytica using two different strategies. In the first one, biocatalysts were produced during solid-state fermentation (SSF-YL), extracted and subsequently used for the hydrolysis of PET and bis(2-hydroxyethyl terephthalate) (BHET), a key intermediate in PET hydrolysis. Biocatalysts were able to act on BHET, yielding terephthalic acid (TPA) (131.31 µmol L−1), and on PET, leading to a TPA concentration of 42.80 µmol L−1 after 168 h. In the second strategy, PET depolymerization was evaluated during submerged cultivations of Y. lipolytica using four different culture media, and the use of YT medium ((w/v) yeast extract 1%, tryptone 2%) yielded the highest TPA concentration after 96 h (65.40 µmol L−1). A final TPA concentration of 94.3 µmol L−1 was obtained on a scale-up in benchtop bioreactors using YT medium. The conversion obtained in bioreactors was 121% higher than in systems with SSF-YL. The results of the present work suggest a relevant role of Y. lipolytica cells in the depolymerization process. [ABSTRACT FROM AUTHOR]