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Polyurethane foam (PUF) pads are widely used in semiconductor manufacturing, particularly for chemical mechanical polishing (CMP). This study prepares PUF composites with microcrystalline cellulose (MCC) and nanocrystalline cellulose (NCC) to improve CMP performance. MCC and NCC were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD), showing average diameters of 129.7 ± 30.9 nm for MCC and 22.2 ± 6.7 nm for NCC, both with high crystallinity (ca. 89%). Prior to preparing composites, the study on the influence of the postbaked step on the PUF was monitored through Fourier-transform infrared spectroscopy (FTIR). After that, PUF was incorporated with MCC/NCC to afford two catalogs of polyurethane foam composites (i.e., PUFC-M and PUFC-N). These PUFCs were examined for their thermal and surface properties using a differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), dynamic mechanical analyzer (DMA), and water contact angle (WCA) measurements. Tgs showed only slight changes but a notable increase in the 10% weight loss temperature (Td10%) for PUFCs, rising from 277 °C for PUF to about 298 °C for PUFCs. The value of Tan δ dropped by up to 11%, indicating improved elasticity. Afterward, tensile and abrasion tests were conducted, and we acquired significant enhancements in the abrasion performance (e.g., from 1.04 mm/h for the PUF to 0.76 mm/h for a PUFC-N) of the PUFCs. Eventually, we prepared high-performance PUFCs and demonstrated their capability toward the practical CMP process.

Advanced oxidation (AOPs) utilizing peroxymonosulfate (PMS) are efficient processes for the degradation of organic pollutants. This study aimed to synthesize and characterize cobalt ferrite (CoFe2O4), graphene oxide (GO), MIL-101(Fe), and their composite structures. The nanomaterials were applied as catalysts by PMS for triclosan (TCS) decomposition. The maximum removal rates of TCS were 49.29, 66.13, 84.04, 89.73, and 100% for PMS alone, CoFe2O4, GO, MIL-101(Fe), and CoFe2O4/MIL-101(Fe)/GO with PMS, respectively. Metal ions leaching declined in CoFe2O4/MIL-101(Fe)/GO/PMS compared with others. Hence, the composite nanomaterials appear to be effective catalysts for the degradation of organic pollutants by PMS activation.

Applying nanotechnology, particularly nano zero-valent iron encapsulated by carboxymethyl cellulose (CMC-nZVI), is considered less expensive and provides high efficiency for the decolorization of textile wastewater. In this study, Congo red dye (CR) was used in synthesized wastewater to evaluate the treatment performance using different composition ratios of CMC-nZVI. At the initial CR concentration of 500 mg/L, decolorization efficiencies increased with the increase of CMC contents. The removal efficiencies reached almost completely at the CMC:Fe2+ ratio of 0.004 within 10 seconds after adding CMC-nZVI to the CR solution. The optimal decolorization rate was observed at the Fe concentration of 1 g/L, with the CR removal efficiency of approximately 90% and a removal capacity of 8.298 g CR/g nZVI. The core principle of dye decolorization is breaking down the chromophore groups (-NN-), which makes the color of the dye, into N–H bonds. CMC-nZVI is a promising key to solving the issues caused by dye-containing wastewater.

This research presents a study on the production of biojet fuel using crude palm kernel oil (CPKO) as a novel source. The aim of the research is to explore an efficient and high-throughput process for biojet production from CPKO. The experiment was conducted using a reactor packed with 5 wt% platinum on carbon (Pt/C). Several key operating variables, such as reaction temperature, hydrogen-to-nitrogen ratio, pressure, gas flow rate, and CPKO flow rate, were investigated to optimize the yield of liquid product and biojet fuel. The optimal conditions determined were a reaction temperature of 400 °C, pressure of 500 psi, CPKO flow rate of 0.02 mL/min, hydrogen-to-nitrogen ratio of 75:25, and gas flow rate of 25 mL/min. Under these conditions, the biojet fuel yield reached 59 %, with a productivity of 330.6 gproduct/gcat-h. The results demonstrated superior production performance compared to other existing processes in the field.

Highlights Sewage sludge (SS) was converted into biodiesel and biochar catalyst. Thermally induced reaction using SS biochar had high biodiesel yield. SS biochar was more effective than porous silica in reaction kinetics.

Abstract Azorubin S (ARS) represents one of the most common and frequently-utilized toxic azo dyes produced from industrial activities. While various conventional treatment techniques could not effectively eliminate ARS from water, heterogeneous metal-based catalyst coupled with monopersulfate (MPS) is a highly-efficient process for eliminating ARS, in which tricobalt tetroxide (Co3O4) has been attracted increasing attention as a preeminent MPS activator due to its outstanding physicochemical properties. However, the nanoscale Co3O4 particles usually pose a limitation of serious agglomeration in the aqueous environment, thus lowering their efficiency. Thus, developing an easy-synthesized and exceptionally efficient Co3O4-based catalyst is crucially paramount. Therefore, in this work, a special hollow-structured oval-like cobalt oxide (abbreviated as HOCO) was successfully constructed using Co-metal organic framework as a precursor, which was then utilized for catalyzing activation of MPS to degrade ARS. This as-obtained HOCO exhibited distinct physicochemical characteristics from commercially-available Co3O4, which subsequently resulted in superior activities for MPS activation in ARS degradation. Specifically, 100% of ARS could be degraded in 30 min with a corresponding reaction kinetic of 0.22 min− 1 by HOCO + MPS system. SO4 •– radicals were validated to be primary reactive species for ARS degradation while the degradation pathway of ARS was also elucidated. This study further provides insightful information about the development of novel hollow-structured Co3O4-based catalyst for catalyzing activation of MPS to remove toxic dyes from water.

LaFexNi1−xO3 perovskite oxides were prepared by the sol–gel method under various conditions, including different pH values (pH 0 and pH 7) and different calcination temperatures (500–800 °C) as well as different Fe/Ni ratios (1/9, 3/7, 5/5, 7/3, 9/1). The samples were examined by XRD, DRS, BET, and SEM to reveal their crystallinity, light-absorption ability, specific surface area, and surface features, respectively. The photocatalytic Fenton reaction was conducted using various LaFexNi1−xO3 perovskite oxides to decompose the methylene blue molecules. Accordingly, the synthesis condition of pH 0, calcination temperature at 700 °C, and Fe/Ni ratio = 7/3 could form LaFe0.7Ni0.3O3 perovskite oxides as highly efficient photocatalysts. Moreover, various conditions during the photocatalytic degradation were verified, such as pH value, catalyst dosage, and the additional amount of H2O2. LaFe0.7Ni0.3O3 perovskite oxides could operate efficiently under pH 3.5, catalyst dosage of 50 mg/150 mL, and H2O2 concentration of 133 ppm to decompose the MB dye in the 1st order kinetic rate constant of 0.0506 s−1.

Although in a critical position in the economy, the paper industry releases a lot of wastewater that requires adequate treatment for sustainable development. This study presents an application of Life cycle assessment (LCA) with the ReCiPe tool on the wastewater treatment plant (WWTP) of a paper factory in Vietnam to evaluate the environmental effect of the individual techniques in WWTP, especially the internal circulation (IC) reactor, a pioneer and practical anaerobic technology. Both Midpoint and Endpoint categories results demonstrated that chemical use and electricity consumption mainly contributed to the environmental impact in the WWTP. The Dissolved air flotation (DAF) and Moving bed biofilm reactor (MBBR) are classified as effective techniques to reduce the impacts on the environment. Moreover, the comparison of LCA between IC and up-flow anaerobic sludge bed (UASB) shows that IC is the better practically green technique for the environment. HIGHLIGHTS Life cycle assessment was applied in a paper mill wastewater treatment plant.; Midpoint and Endpoint indicators were employed to evaluate environmental impact.; Two scenarios of electricity generating from biogas between Internal circulation and up-flow anaerobic sludge bed were investigated.; Chemicals use and energy consumption were determined to be the most factors to damage indicators.;

Even though transition metals can activate Oxone to degrade toxic contaminants, bimetallic materials possess higher catalytic activities because of synergistic effects, making them more attractive for Oxone activation. Herein, nanoscale CuCo-bearing N-doped carbon (CuCoNC) can be designed to afford a hollow structure as well as CuCo species by adopting cobaltic metal organic frameworks as a template. In contrast to Co-bearing N-doped carbon (CoNC), which lacks the Cu dopant, CuCo alloy nanoparticles (NPs) are contained by the Cu dopant within the carbonaceous matrix, giving CuCoNC more prominent electrochemical properties and larger porous structures and highly nitrogen moieties. CuCoNC, as a result, has a significantly higher capability compared to CoNC and Co3O4 NPs, for Oxone activation to degrade a toxic contaminant, Rhodamine B (RDMB). Furthermore, CuCoNC+Oxone has a smaller activation energy for RDMB elimination and maintains its superior effectiveness for removing RDMB in various water conditions. The computational chemistry insights have revealed the RDMB degradation mechanism. This study reveals that CuCoNC is a useful activator for Oxone to eliminate RDMB.

Nanomaterials (NMs) have piqued the attention of scientists and researchers across many biomedical sciences due to their superior physical, chemical, and magnetic properties. The efficacy and efficiency of NMs depend on adapting to specific site conditions and soil composition. NMs have lately received much attention in the context of polycyclic aromatic hydrocarbons (PAHs) polluted soil remediation and water mitigation because of their unique properties resulting from their nanoscale sizes. The remediation of hazardous PAHs in water and soil is a hot research subject. Because the exposure of PAHs in water and soil results in pollution, which raises major human health concerns. The current review reports novel advancements in NMs that subsidize enhancement for degradation of PAHs. Challenges to the fabrication of high activity-based photocatalytic materials are also discussed. Furthermore, this review delivers exclusive and wide-ranging perspectives on the fabrication of nanomaterial-based photocatalytic systems. The knowledge of both soil remediation and water mitigation is also updated.

Tremendous amounts of plastic waste are generated daily. The indiscriminate disposal of plastic waste can cause serious global environmental issues, such as leakages of microplastics into the ecosystem. Thus, it is necessary to find a more sustainable way to reduce the volume of plastic waste by converting it into usable materials. Pyrolysis provides a sustainable solution for the production of carbonaceous materials (e.g., char). Plastic-waste-derived char can be used as an additive in epoxy composites to improve the properties and performance of neat epoxy resins. This review compiles relevant knowledge on the potential of additives for epoxy composites originating from plastic waste. It also highlights the potential of plastic-waste-derived char materials for use in materials in various industries.

The invention of an easy synthetic approach for extremely impactful nanomaterials (NMs) is one of the crucial research areas in modern science and engineering. In the present work, we describe a cost-effective, simple, rapid and environmentally gracious biogenic fabrication of nickel/nickel oxide nanoparticles (Ni/NiO NPs) using Gymnema sylvestre as a natural fuel. The textural characteristics of as-prepared Ni/NiO NPs were explored using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectra (DRS), photoluminescence spectroscopy (PL), field-emission scanning electron microscope (FESEM), energy dispersive X-ray analysis (EDX), and high-resolution transmission electron microscopy (HRTEM). XRD affirmed the crystalline nature and phase formation of Ni/NiO NPs. The FTIR spectrum ascertains the formation of Ni/NiO NPs, and the band gap of 4.29 eV is revealed from DRS studies. Ni/NiO NPs display an intense emission peak at 576.2 nm in their PL spectrum. The fabrication of pseudo-spherical Ni/NiO NPs was displayed by FESEM and HRTEM images. The particle size obtained from HRTEM was 21 nm, which resembles the median crystallite size ascertained from the XRD data. Additionally, the plausible mechanism for Ni/NiO NPs formation is illustrated. Moreover, as-synthesized Ni/NiO NPs displayed considerable antifungal potential against Candida albicans and Aspergillus niger. Results revealed that the Gymnema sylvestre leaves extract can synthesize Ni/NiO NPs with appealing biological effectiveness for application in the nanomedicine sector.

Phosphorus (P) is an essential yet non-renewable nutrient, so recovering it from urine is getting more attention since it has a high concentration of nutrients. This study aimed to investigate the impacts of temperature, storage condition on urine's characteristics, and the effects of pH, Mg:P ratio, and calcium (Ca) ion on yielded magnesium phosphate hydrate (Mg3(PO4)2•xH2O) crystallization from fresh urine. The results indicated that the urine stored at 4 °C in a sealed environment created less spontaneous precipitation. The findings showed that the favorable condition for Mg3(PO4)2•xH2O recovery was at pH 10.5 and Mg:P of 1.3. The XRD analysis confirmed that P was crystallized as Mg3(PO4)2•xH2O phase with an average particle size of 0.5 mm. Furthermore, SEM-EDS images suggested the Ca and K might co-precipitate with Mg3(PO4)2•xH2O. These findings indicate that the potential of P recovery from nutrient-rich wastewater can both reduce environmental pollution and profit from phosphate fertilizers.

Hydrogen peroxide (H2O2) is one of the most promising, green, and effective oxidants that can be used in different applications. In this study, zeolitic imidazolate frameworks (ZIFs), consisting of organic ligands and metal sites, were selectively prepared from zinc or nickel nitrate solutions for use in photocatalytic H2O2 production. High concentrations of zinc nitrate solution provided more metal sites to coordinate with 2-methylimidazole, producing ZIF-8 with larger particle size, whereas low zinc nitrate concentrations resulted in more interconnected N–H⋯N hydrogen bonds, forming 2D-layered ZIF-L, with smaller particle size. Various concentrations of zinc and nickel nitrate solutions produced ZIFs that exhibited ZIF-8 or ZIF-L topology, with bandgap energies of 5.45 and 4.85 eV, respectively. These samples could serve as promising photocatalyst for the successful production of H2O2 under Xenon lamp irradiation.

As cobalt (Co) has been the most useful element for activating Oxone to generate SO4•−, this study aims to develop a hierarchical catalyst with nanoscale functionality and macroscale convenience by decorating nanoscale Co-based oxides on macroscale supports. Specifically, a facile protocol is proposed by utilizing Cu mesh itself as a Cu source for fabricating CuCo2O4 on Cu mesh. By changing the dosages of the Co precursor and carbamide, various nanostructures of CuCo2O4 grown on a Cu mesh can be afforded, including nanoscale needles, flowers, and sheets. Even though the Cu mesh itself can be also transformed to a Cu-Oxide mesh, the growth of CuCo2O4 on the Cu mesh significantly improves its physical, chemical, and electrochemical properties, making these CuCo2O4@Cu meshes much more superior catalysts for activating Oxone to degrade the Azo toxicant, Acid Red 27. More interestingly, the flower-like CuCo2O4@Cu mesh exhibits a higher specific surface area and more superior electrochemical performance, enabling the flower-like CuCo2O4@Cu mesh to show the highest catalytic activity for Oxone activation to degrade Acid Red 27. The flower-like CuCo2O4@Cu mesh also exhibits a much lower Ea of Acid Red 27 degradation than the reported catalysts. These results demonstrate that CuCo2O4@Cu meshes are advantageous heterogeneous catalysts for Oxone activation, and especially, the flower-like CuCo2O4@Cu mesh appears as the most effective CuCo2O4@Cu mesh to eliminate the toxic Acid Red 27.

Quickly changing fashion trends generate tremendous amounts of textile waste globally. The inhomogeneity and complicated nature of textile waste make its recycling challenging. Hence, it is urgent to develop a feasible method to extract value from textile waste. Pyrolysis is an effective waste-to-energy option to processing waste feedstocks having an inhomogeneous and complicated nature. Herein, pyrolysis of denim jeans waste (DJW; a textile waste surrogate) was performed in a continuous flow pyrolyser. The effects of adding sodium carbonate (Na2CO3; feedstock/Na2CO3 = 10, weight basis) to the DJW pyrolysis on the yield and composition of pyrolysates were explored. For the DJW pyrolysis, using Na2CO3 as an additive increased the yields of gas and solid phase pyrolysates and decreased the yield of liquid phase pyrolysate. The highest yield of the gas phase pyrolysate was 34.1 wt% at 800 °C in the presence of Na2CO3. The addition of Na2CO3 could increase the contents of combustible gases such as H2 and CO in the gas phase pyrolysate in comparison with the DJW pyrolysis without Na2CO3. The maximum yield of the liquid phase pyrolysate obtained with Na2CO3 was 62.5 wt% at 400 °C. The composition of the liquid phase pyrolysate indicated that the Na2CO3 additive decreased the contents of organic acids, which potentially improve its fuel property by reducing acid value. The results indicated that Na2CO3 can be a potential additive to pyrolysis to enhance energy recovery from DJW.

Providing safe drinking water and clean water is becoming a more challenging task all around the world. Although some critical issues and limits remain unsolved, implementing ecologically sustainable nanomaterials (NMs) with unique features, e.g., highly efficient and selective, earth-abundance, renewability, low-cost manufacturing procedures, and stability, has become a priority. Carbon nanoparticles (NPs) offer tremendous promise in the sectors of energy and the environment. However, a series of far more ecologically friendly synthesis techniques based on natural, renewable, and less expensive waste resources must be explored. This will reduce greenhouse gas emissions and harmful material extraction and assist the development of green technologies. The progress achieved in the previous 10 years in the fabrication of novel carbon-based NMs utilizing waste materials as well as natural precursors is reviewed in this article. Research on carbon-based NPs and their production using naturally occurring precursors and waste materials focuses on this review research. Water treatment and purification using carbon NMs, notably for industrial and pharmaceutical wastes, has shown significant potential. Research in this area focuses on enhanced carbonaceous NMs, methods, and novel nano-sorbents for wastewater, drinking water, groundwater treatment, as well as ionic metal removal from aqueous environments. Discussed are the latest developments and challenges in environmentally friendly carbon and graphene quantum dot NMs.

Bis(4-hydroxyphenyl)methanone (BHPM), a common ultraviolet stabilizer and filter (USF), is extensively added in sunscreens; however, BHPM is proven as an endocrine disruptor, posing a serious threat to aquatic ecology, and BHPM should be then removed. As sulfate radical (SO4•−) could be useful for eliminating emerging contaminants, oxone appears as a favorable source reagent of SO4•− for degrading BHPM. Even though cobalt is a useful catalyst for activating oxone to generate SO4•−, it would be even more promising to utilize ambient-visible-light irradiation to enhance oxone activation using cobaltic catalysts. Therefore, in contrast to the conventional cobalt oxide, cobalt titanium oxide (CTO) was investigated for chemical and photocatalytic activation of oxone to eliminate BHPM from water. Especially, a special morphology of nanosheet-assembled configuration of CTO was designed to maximize active surfaces and sites of CTO. Thus, CTO outperforms Co3O4 and TiO2 in degrading BHPM via oxone activation. Furthermore, the substituent of Ti enabled CTO to enhance absorption of visible light and possessed a much smaller Eg. These photocatalytic properties intensified CTO’s activity for oxone activation. CTO possessed a significantly smaller Ea of degradation of USFs than other catalytic systems. Mechanistic insight for degrading BHPM by CTO + oxone was explicated for identifying contribution of reactive oxygen species to BHPM degradation. The BHPM degradation pathway was also investigated and unveiled in details via the DFT calculation. These results validated that CTO is a superior cobaltic alternative for activating oxone to eliminate BHPM.

The utilization of CO2 attracts much research attention because of global warming. The CO2/epoxide cycloaddition reaction is one technique of CO2 utilization. However, homogeneous catalysts with both Lewis acidic and basic and toxic solvents, such as DMF, are needed in the CO2/epoxide cycloaddition reaction. As a result, this study focuses on the development of heterogeneous catalysts with both Lewis acidic and basic sites for the CO2 utilization of the CO2/epoxide cycloaddition reactions without the addition of a DMF toxic solvent. For the first time, the Zr–Mg mixed oxide aerogels with Lewis acidic and basic sites are synthesized for the CO2/propylene oxide (PO) cycloaddition reactions. To further increase the basic sites, 3-Aminopropyl trimethoxysilane (APTMS) with -NH2 functional group is successfully grafted on the Zr–Mg mixed oxide aerogels. The results indicate that the highest yield of propylene carbonate (PC) is 93.1% using the as-developed APTMS-modified Zr–Mg mixed oxide aerogels. The as-prepared APTMS-modified Zr–Mg mixed oxide aerogels are great potential in industrial plants for CO2 reduction in the future.

Nitrogen-containing phenolic contaminants (NCPCs) represent typical pollutants of industrial wastewaters. As catalytic reduction of NCPCs is a useful technique and Cu is an efficient metal catalyst, Cu-carboxylate frameworks (CuCF) are favorable materials. However, they are in powder form, making them difficult to use; thus, in this study, CuCF was grown on macroscale supports. Herein, we present a facile approach to develop such a CuCF composite by directly using a Cu mesh to grow CuCF on the mesh through a single-step electrochemical synthesis method, forming CuCF mesh (CFM). CFM could be further modified to afford CuCF mesh with amines (NH2) (CFNM), and CuCF mesh with carboxylates (COOH) (CFCM). These CuCF meshes are compared to investigate how their physical and chemical characteristics influenced their catalytic behaviors for reduction/hydrogenation of NPCPs, including nitrophenols (NPs) and dyes. Their nanostructures and surface properties influence their behaviors in catalytic reactions. In particular, CFCM appears to be the most efficient mesh for catalyzing 4-NP, with a much higher rate constant. CFCM also shows a significantly lower Ea (28.1 kJ/mol). CFCM is employed for many consecutive cycles, as well as convenient filtration-type 4-NP reduction. These CuCF meshes can also be employed for decolorization of methylene blue and methyl orange dyes via catalytic hydrogenation.

Climacteric fruits are harvested before they are ripened to avoid adverse damages during transport. The unripe fruits can undergo ripening processes associated with rind color changes on exposure to ethanol vapors. Although rind coloration is a common indicator showing fruit maturity, the attribute does not provide reliable assessment of maturity especially for melons. Herein, we report the achievement of sensitive and reversible melon maturity detection using macroporous hydrogel photonic crystals self-assembled by a roll-to-roll compatible doctor-blade-coating technology. The consumption of applied ethanol vapor during melon ripening results in less condensation of ethanol vapor in the pores (250 nm in diameter), leading to a distinct blue-shift of the optical stop band from 572 to 501 nm and an obvious visual colorimetric readout from yellow green to blue. Moreover, the dependence of the color change on Brix value within the melon has also been evaluated in the study.

As CeO2 is a useful catalyst for soot elimination, it is important to develop CeO2 with higher contact areas, and reactivities for efficient soot oxidation and catalytic soot oxidation are basically controlled by structures and surface properties of catalysts. Herein, a Ce-Metal organic framework (MOFs) consisting of Ce and benzene-1,3,5-tricarboxylic acid (H3BTC) is employed as the precursor as CeBTC exhibits a unique bar-like high-aspect-ratio morphology, which is then transformed into CeO2 with a nanoscale bar-like configuration. More importantly, this CeO2 nanobar (CeONB) possesses porou, and even hollow structures, as well as more oxygen vacancies, enabling CeONB to become a promising catalyst for soot oxidation. Thus, CeONB shows a much higher catalytic activity than commercial CeO2 nanoparticle (comCeO) for soot oxidation with a significantly lower ignition temperature (Tig). Moreover, while soot oxidation by comCeO leads to production of CO together with CO2, CeONB can completely convert soot to CO2. The tight contact mode also enables CeONB to exhibit a very low Tig of 310 °C, whereas the existence of NO also enhances the soot oxidation by CeONB to reduce the Tig. The mechanism of NO-assisted soot oxidation is also examined, and validated by DRIFTS to identify the formation and transformation of nitrogen-containing intermediates. CeONB is also recyclable over many consecutive cycles and maintained its high catalytic activity for soot oxidation. These results demonstrate that CeONB is a promising and easily prepared high-aspect-ratio Ce-based catalyst for soot oxidation.

Reversible-deactivation radical polymerization (RDRP) serves as a powerful tool nowadays for the preparations of unique linear and non-linear macromolecules. In this study, enhanced spin capturing polymerizations (ESCPs) of styrene (St) and tert-butyl acrylate (tBA) monomers were, respectively, conducted in the presence of difunctional (1Z,1′Z)-1,1′-(1,4-phenylene) bis (N-tert-butylmethanimine oxide) (PBBN) nitrone. Four-arm (PSt)4 and (PtBA)4 star macroinitiators (MIs) can be afforded. By correspondingly switching the second monomer (i.e., tBA and St), miktoarm star copolymers (μ-stars) of (PSt)2-μ-(PtBA-b-PSt)2 and (PtBA)2-μ-(PSt-b-PtBA)2) were thus obtained. We further conducted hydrolysis of the PtBA segments to PAA (i.e., poly(acrylic acid)) in μ-stars to afford amphiphilic μ-stars of (PSt)2-μ-(PAA-b-PSt)2 and (PAA)2-μ-(PSt-b-PAA)2. We investigated each polymerization step and characterized the obtained two sets of “sequence-isomeric” μ-stars by FT-IR, 1H NMR, differential scanning calorimeter (DSC), and thermogravimetric analysis (TGA). Interestingly, we identified their physical property differences in the case of amphiphilic μ-stars by water contact angle (WCA) and atomic force microscopy (AFM) measurements. We thus proposed two microstructures caused by the difference of polymer chain sequences. Through this polymerization transformation (Ŧ) approach (i.e., ESCP-Ŧ-NMP), we demonstrated an interesting and facile strategy for the preparations of μ-stars with adjustable/switchable interior and exterior polymer structures toward the preparations of various nanomaterials.

Herein, the pyrolysis of two types of single-use disposable waste (single-use food containers and corrugated fiberboard) was investigated as an approach to cleanly dispose of municipal solid waste, including plastic waste. For the pyrolysis of single-use food containers or corrugated fiberboard, an increase in temperature tended to increase the yield of pyrolytic gas (i.e., non-condensable gases) and decrease the yield of pyrolytic liquid (i.e., a mixture of condensable compounds) and solid residue. The single-use food container-derived pyrolytic product was largely composed of hydrocarbons with a wide range of carbon numbers from C1 to C32, while the corrugated fiberboard-derived pyrolytic product was composed of a variety of chemical groups such as phenolic compounds, polycyclic aromatic compounds, and oxygenates involving alcohols, acids, aldehydes, ketones, acetates, and esters. Changes in the pyrolysis temperature from 500 °C to 900 °C had no significant effect on the selectivity toward each chemical group found in the pyrolytic liquid derived from either the single-use food containers or corrugated fiberboard. The co-pyrolysis of the single-use food containers and corrugated fiberboard led to 6 times higher hydrogen (H2) selectivity than the pyrolysis of the single-use food containers only. Furthermore, the co-pyrolysis did not form phenolic compounds or polycyclic aromatic compounds that are hazardous environmental pollutants (0% selectivity), indicating that the co-pyrolysis process is an eco-friendly method to treat single-use disposable waste.

In this study, perovskite ZnTiO3 photocatalysts were fabricated by the sol–gel method. The photocatalytic capability was verified by the degradation of the emerging contaminant, the antibiotic amoxicillin (AMX). For the preparation, the parameters of the calcination temperature and the additional amount of polyvinylpyrrolidone (PVP) and ammonia are discussed, including the calcining temperature (500, 600, 700, 800 °C), the volume of ammonia (750, 1500, 3000 μL), and the weight of PVP (3 g and 5 g). The prepared perovskite ZnTiO3 was characterized by XRD, FESEM, BET, and UV-Vis. It is shown that the perovskite ZnTiO3 photocatalysts are structurally rod-like and ultraviolet light-responsive. Consequently, the synthesis conditions for fabricating the perovskite ZnTiO3 photocatalysts with the highest photocatalytic performance were a calcining temperature of 700 °C, an additional ammonia amount of 1500 μL, and added PVP of 5 g. Moreover, the photocatalytic degradation of perovskite ZnTiO3 photocatalysts on other pollutants, including the antibiotic tetracycline (TC), methyl orange (MO), and methylene blue (MB) dyes, was also examined. This provides the basis for the application of perovskite ZnTiO3 as a photocatalyst to decompose emerging contaminants and organic pollutants in wastewater treatment.

Herein, the pyrolysis of low-density polyethylene (LDPE) scrap in the presence of a H-ZSM-11 zeolite was conducted as an effort to valorize plastic waste to fuel-range chemicals. The LDPE-derived pyrolytic gas was composed of low-molecular-weight aliphatic hydrocarbons (e.g., methane, ethane, propane, ethylene, and propylene) and hydrogen. An increase in pyrolysis temperature led to increasing the gaseous hydrocarbon yields for the pyrolysis of LDPE. Using the H-ZSM-11 catalyst in the pyrolysis of LDPE greatly enhanced the content of propylene in the pyrolytic gas because of promoted dehydrogenation of propane formed during the pyrolysis. Apart from the light aliphatic hydrocarbons, jet fuel-, diesel-, and motor oil-range hydrocarbons were found in the pyrolytic liquid for the non-catalytic and catalytic pyrolysis. The change in pyrolysis temperature for the catalytic pyrolysis affected the hydrocarbon compositions of the pyrolytic liquid more materially than for the non-catalytic pyrolysis. This study experimentally showed that H-ZSM-11 can be effective at producing fuel-range hydrocarbons from LDPE waste through pyrolysis. The results would contribute to the development of waste valorization process via plastic upcycling.

This review presents the latest developments in (bio)degradable approaches and functional aliphatic polyesters and polycarbonates prepared by typical ring-opening polymerization (ROP) of lactones and trimethylene carbonates. It also considers several recent innovative synthetic methods including radical ring-opening polymerization (RROP), atom transfer radical polyaddition (ATRPA), and simultaneous chain- and step-growth radical polymerization (SCSRP) that produce aliphatic polyesters. With regard to (bio)degradable approaches, we have summarized several representative cleavable linkages that make it possible to obtain cleavable polymers. In the section on functional aliphatic polyesters, we explore the syntheses of specific functional lactones, which can be performed by ring-opening copolymerization of typical lactone/lactide monomers. Last but not the least, in the recent innovative methods section, three interesting synthetic methodologies, RROP, ATRPA, and SCSRP are discussed in detail with regard to their reaction mechanisms and polymer functionalities.

Hexamethylenediamine (HMDA), a chemical for producing nylon, was produced on Raney Ni and Raney Co catalysts via the hydrogenation of adiponitrile (ADN). HMDA was hydrogenated from ADN via 6-aminohexanenitrile (AHN). For the two catalysts, the effects of five different reaction parameters (reaction temperature, H2 pressure, catalyst loading, and ADN/HMDA ratio in the reactant) on the hydrogenation of ADN were investigated. Similar general trends demonstrating the dependence of ADN hydrogenation on the reaction conditions for both catalysts were observed: higher temperature (60–80 °C) and H2 pressure, as well as lower ADN/catalyst and ADN/HMDA ratios, led to higher HMDA yields. A further increase in temperature from 80 to 100 °C increased the HMDA yield from 90.5 to 100% for the Raney Ni catalyst, but did not affect the HMDA yield (85~87%) for the Raney Co catalyst. A 100% HMDA yield (the highest yield reported to date) was also achieved via ADN hydrogenation over the Raney Ni catalyst, with a high HMDA content in the reactant (e.g., ADN/HMDA volumetric ratio of 0.06). No sign of metal leaching into the product solution was found, meaning that the Raney Ni and Raney Co catalysts were stable during ADN hydrogenation.