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During thermal utilization of biomass, a complex array of reactions ensues in the oxidative environment between fragments of the biomass and reactive species. In the low-temperature window, hydroperoxyl (HO 2) radicals assume a central role prior to the establishment of the O/H radical pool. Anisole, cresol, guaiacol and vanillin are often utilized as representative model compounds to comprehend the combustion chemistry of the phenolic entities in biomass and oxygen-containing derived bio-oil. This paper reports thermo-kinetic parameters for the reactions of HO2 radicals with anisole, cresol, guaiacol and vanillin. Computed activation enthalpies entail facile values for H abstraction from the side-chain functional groups in the investigated compounds. H abstraction from the hydroxyl groups incurs lower activation energies in reference to methyl sites in cresol and guaiacol. Hence, H abstraction from the OH sites in these two molecules proceeds at a faster reaction rate constant when compared to abstraction from the methyl site. In the vanillin molecule, abstraction from the aldehydic and hydroxyl sites portrays comparable importance. The effect of scaling vibrational frequencies and the type of applied quantum tunneling on the computed reaction rate constants were thoroughly explored. Analysis of entropies of activation indicates that the transition states exhibit a product-like character. While ignition delay times of fuels often exhibit a profound sensitivity towards initial H abstraction reactions by HO2, we found that ignition delay times of the four title molecules remain almost unchanged when updating literature kinetics models with new reaction rate constants calculated herein. It is anticipated that reported outcomes from this study aid in formulating a better understanding of the complex chemical reactions that dictate oxidative decomposition of oxygenated bio-oil model compounds. The work reports thermo-kinetic parameters for the reactions of HO2 radicals with prominent biomass model compounds. Abstraction from various sites have been explored. The effect of the title reaction in the ignition delay times of these compounds is rather limited. [ABSTRACT FROM AUTHOR]

As candidates for intravesical exfoliants to treat bladder cancer, we have prepared fourteen new imidazolium compounds substituted at the 2 position. These compounds were produced by use of the Knoevenagel reaction between a series of aryl aldehydes and 2‐methyl imidazolium salts. Two azolium systems were examined (benzimidazole and 4,5‐dichloroimidazole) and each of these heterocycles are substituted off the nitrogen atom positions with naphthalen‐2‐ylmethyl groups. NMR spectroscopy confirms formation of the carbon‐carbon double bond, and X‐ray crystallography confirmed that the alkenes adopt the E conformation. These new imidazolium salts were evaluated for their chemotherapeutic activity using the NCI‐60 Human Tumor Cell Line Screen, and we observed that the benzimidazolium systems were more toxic than the dichloroimidazolium systems, and that the methyl phenol ether or dimethyl aniline modified compounds showed the highest activities. [ABSTRACT FROM AUTHOR]

Rapid and visual detection of SARS‐CoV‐2 variants is vital for timely assessment of variant transmission in resource‐limited settings. Here, a closed‐tube, two‐stage, mixed‐dye‐based isothermal amplification method with ribonuclease‐cleavable enhanced probes (REP), termed REP‐TMAP, for dual‐visualization detection of SARS‐CoV‐2 variants including JN.1, BA.2, BA.4/5, and Delta is introduced. The first stage of REP‐TMAP is reverse transcription recombinase polymerase amplification and the second stage is dual‐visualization detection synergistically mediated by the REP and the mixed dyes of cresol red and hydroxy naphthol blue. In REP‐TMAP reaction, the color change under ambient light indicates SARS‐CoV‐2 infection, while the fluorescence change under blue light excitation specifies variant type. On detecting transcribed RNA of SARS‐CoV‐2 spike gene, this assay is rapid (within 40 min), highly sensitive (10–200 copies per reaction), and highly specific (identification of single‐base mutations). Furthermore, the assay has been clinically validated to accurately detect JN.1, BA.2, and BA.4/5 variants from 102 human oropharyngeal swabs. The proposed assay therefore holds great potentials to provide a rapid, dual‐visualization, sensitive, specific, point‐of‐care detection of SARS‐CoV‐2 variants and beyond. [ABSTRACT FROM AUTHOR]

• Erythrina fusca undergo acid-base extraction employing HCl and tartaric acid. • 1H NMR chemometric analysis was employed to vary phytochemical profiles of extracts. • HCl was selective in extracting alkaloids compared to tartaric acid. • The value of targeting extraction process for alkaloids. Erythrina fusca Lour. (Fabaceae) has been used traditionally to relieve toothache and migraine headaches, cleansing putrid ulcers, and reducing skin inflammations and irritation. Interestingly, most of the reported biological activities on the plant are attributed to its Erythrina alkaloids which are usually extracted through the acid-base method. While the selection of acids for the extraction process is crucial, there is limited information on comparing the efficacy of strong organic and inorganic acids in extracting Erythrina alkaloids, and, more broadly, other types of alkaloids. In this study, comparison between hydrochloric acid (HCl) and tartaric acid (H 2 T) was made to extract the Erythrina alkaloids. From the same mass (10 g) of the crude methanolic leaf extract, a significantly higher (9-fold) alkaloidal yield was obtained using H 2 T compared to the HCl. The alkaloidal extracts displayed different proton nuclear magnetic resonance (1H NMR) profile where identification of their phytochemical constituents was done extensively through comparison with respective data of previously isolated compounds from the Erythrina species. Forty-seven phytochemicals were identified in the HCl extract and they were mostly alkaloids. While the H 2 T extract not only contained alkaloids, but also flavonoids, and pterocarpans. Cumulatively, 83 phytochemicals were identified from the extracts, including 35 alkaloids, 18 flavonoids, 14 pterocarpans, 9 terpenes, 3 phenols, and 4 saponins. Based on multivariate analysis (MVDA), the alkaloids erysodine (1), erysovine (2), erysopine (3), warangalone (39), calopocarpin (53), and dolichin A (60) were found in both alkaloidal extracts. The PLS-DA model further identified the variation in the two extracts where the HCl extract was characterized by the flavonoids lupinifolin (41) and erythrisenegalone (43). Conversely, the H 2 T extract contained a broader range of phytochemicals, including the alkaloids glucoerysodine (21) and erythratidinone (28), the flavonoids 5,3′-dihydroxy-4′‑methoxy-5′-(3-methyl-1,3-butadienyl)-2′′,2′′dimethylpyrano-[5,6:6,7]-isoflavanone (51), 5,3′-dihydroxy-5′-(3‑hydroxy-3-methyl-1-butenyl)-4′‑methoxy-2′′,2′′dimethylpyrano-[5,6:6,7]-isoflavanone (52), and catechin (82), the pterocarpans calopocarpin (53) and sandwicensin (63), the terpenes loliolide (70), ursolic acid (80), propyloxyamyrin (83), and stigmast-3-en-4-one (73), the saponins sigmoisides A, B, and E (75, 76 , and 77), and the phenol methyl gallate (81). The present findings highlight the value of targeting the extraction process for alkaloids, in this instance Erythrina alkaloids, using different type of acids. Furthermore, these compounds may be considered potential markers that were selectively extracted through the acid-base extraction process. [ABSTRACT FROM AUTHOR]

Corrosion is a major issue in steel applications for industrial purposes and other fields. In order to combat this, extensive research has been done on anti-corrosive materials, resulting in the development of various types of precursors. This work presents a polyurethane-based material that uses benzoxazine as a monomer. The synthesized monomer has been characterized extensively and systematically using NMR, UV-visible, and FT-IR spectroscopic methods. The monomer's electronic properties have been explained by DFT analysis, including FMO's analysis and molecular mapping studies. Moreover, three different ratios of polyurethane precursor have been used to create an anti-corrosive co-polymer material. The hygroscopic nature and gel formation of the synthesized polymer have been tested, demonstrating superior results. Additionally, the Tafel experiment was used to test the coated polymer's activity, and the results showed that it was more active than bare mild steel. [ABSTRACT FROM AUTHOR]

Maskwio'mi (Mi'kmaw language for "oil made from birch bark") is a traditional topical skin medicine of the Mi'kmaq people of Atlantic Canada and is produced in a torrefaction process by heating birch bark (Betula papyrifera, paper birch) inside a metal container in a fire. The resulting viscous, oily mixture is traditionally mixed with goose fat or bear grease to create a topical salve that is subsequently applied to affected skin areas. When birch bark is exposed to high temperatures, pyrolytic chemical processes produce a complex mixture of pharmacologically active compounds, including potentially harmful side products such as ortho-, meta-, and para-cresol. This study discusses the qualitative and quantitative GC-MS analysis of cresols found in maskwio'mi and the challenges of the complex organic matrix. Using caffeine as an internal standard, ortho-, meta-, and para-cresol in birch bark extract were determined to be in the approximate order of 50–1500 ppm range with 3.24 ± 0.09 × 102 ng mg−1 (324 ppm), 8.7 ± 1.0 × 102 ng mg−1 (87 ppm), and 12.4 ± 1.6 × 102 ng mg−1 (1240 ppm), respectively, and thus suitable by Health Canada and FDA cosmetics regulation standards when the extract is co-formulated in creams to concentrations of 0.1–5 wt.% for topical use. [ABSTRACT FROM AUTHOR]

Emergent strategies to valorize lignin, an abundant but underutilized aromatic biopolymer, include tandem processes that integrate chemical depolymerization and biological catalysis. To date, aromatic monomers from C–O bond cleavage of lignin have been converted to bioproducts, but the presence of recalcitrant C–C bonds in lignin limits the product yield. A promising chemocatalytic strategy that overcomes this limitation involves phenol methyl protection and autoxidation. Incorporating this into a tandem process requires microbial cell factories able to transform the p-methoxylated products in the resulting methylated lignin stream. In this study, we assessed the ability of Rhodococcus jostii RHA1 to catabolize the major aromatic products in a methylated lignin stream and elucidated the pathways responsible for this catabolism. RHA1 grew on a methylated pine lignin stream, catabolizing the major aromatic monomers: p-methoxybenzoate (p-MBA), veratrate, and veratraldehyde. Bioinformatic analyses suggested that a cytochrome P450, PbdA, and its cognate reductase, PbdB, are involved in p-MBA catabolism. Gene deletion studies established that both pbdA and pbdB are essential for growth on p-MBA and several derivatives. Furthermore, a deletion mutant of a candidate p-hydroxybenzoate (p-HBA) hydroxylase, ΔpobA, did not grow on p-HBA. Veratraldehyde and veratrate catabolism required both vanillin dehydrogenase (Vdh) and vanillate O-demethylase (VanAB), revealing previously unknown roles of these enzymes. Finally, a ΔpcaL strain grew on neither p-MBA nor veratrate, indicating they are catabolized through the β-ketoadipate pathway. This study expands our understanding of the bacterial catabolism of aromatic compounds and facilitates the development of biocatalysts for lignin valorization. IMPORTANCE Lignin, an abundant aromatic polymer found in plant biomass, is a promising renewable replacement for fossil fuels as a feedstock for the chemical industry. Strategies for upgrading lignin include processes that couple the catalytic fractionation of biomass and biocatalytic transformation of the resulting aromatic compounds with a microbial cell factory. Engineering microbial cell factories for this biocatalysis requires characterization of bacterial pathways involved in catabolizing lignin-derived aromatic compounds. This study identifies new pathways for lignin-derived aromatic degradation in Rhodococcus, a genus of bacteria well suited for biocatalysis. Additionally, we describe previously unknown activities of characterized enzymes on lignin-derived compounds, expanding their utility. This work advances the development of strategies to replace fossil fuel-based feedstocks with sustainable alternatives. [ABSTRACT FROM AUTHOR]

The present work focuses on the investigation of protective coatings produced on zinc from chitosan (Chit) and an anionic dye, namely cresol red. Cresol red (CR) fulfills the basic requirements to be used as a corrosion inhibitor because it possesses a relatively high molecular weight and includes in its structure oxygen and sulfur atoms as well as aromatic rings. Moreover, it is an anionic compound that can interact with positively charged chitosan to produce reinforced coatings for zinc anti-corrosion protection. The influence of cresol red as a possible corrosion inhibitor for zinc substrates was investigated either in solution or incorporated in Chit coatings. Two preparation methods for the coatings were used: (i) Chit coating impregnation by immersion in the CR solution after Chit deposition on Zn, and (ii) chitosan mixing with the CR solution before applying the dip-coating technique. Potentiodynamic polarization curves were used to determine the kinetic parameters of the corrosion process. Long-term measurements were carried out in wet/dry cyclic conditions by using electrochemical impedance spectroscopy. EIS measurements recorded in 0.2 g/L Na2SO4 at pH = 7 show an important increase in the impedance of the coatings occurring from the first until the fifty-fifth day in a row, in dry–wet cycles. This increase is due to the beneficial effect of CR incorporated in Chitosan and could be, at least partially, related to a consolidation of the Chit coating structure in the presence of CR by crosslinking between Chit and CR molecules. The structure of the coatings was studied, and the interactions between chitosan and cresol red were put into evidence by using FT-IR spectroscopy. Adhesion and wettability measurements were also carried out. The adhesion of Chit incorporating CR on Zn was better than that on glass substrates and reached ~99.99%, suggesting a better affinity of the chitosan coating towards the Zn substrate due to the existence of ZnO on the substrate surface. All the results show that CR could be used on zinc as a corrosion inhibitor incorporated in chitosan at basic pHs, but without taking advantage of its pH-indicating properties, which are lost due to the interactions occurring between the positively charged biopolymer and the negatively charged dye molecule. The preparation method of Chit coating impregnation with CR by immersion in the solution after deposition on Zn led to poorer results than the method in which chitosan was previously mixed with CR before applying the dip-coating technique. [ABSTRACT FROM AUTHOR]

Since SARS-CoV-2 is a highly transmissible virus, a rapid and accurate diagnostic method is necessary to prevent virus spread. We aimed to develop and evaluate a new rapid colorimetric reverse transcription loop--mediated isothermal amplification (RT-LAMP) assay for SARS-CoV-2 detection in a single closed tube. Nasopharyngeal and throat swabs collected from at-risk individuals testing for SARS-CoV-2 were used to assess the sensitivity and specificity of a new RT-LAMP assay against a commercial qRT-PCR assay. Total RNA extracts were submitted to the RT-LAMP reaction under optimal conditions and amplified at 65 °C for 30 min using three sets of specific primers targeting the nucleocapsid gene. The reaction was detected using two different indicator dyes, hydroxynaphthol blue (HNB) and cresol red. A total of 82 samples were used for detection with HNB and 94 samples with cresol red, and results were compared with the qRT-PCR assay. The sensitivity of the RT-LAMP-based HNB assay was 92.1% and the specificity was 93.2%. The sensitivity of the RT-LAMP-based cresol red assay was 80.3%, and the specificity was 97%. This colorimetric feature makes this assay highly accessible, low-cost, and user-friendly, which can be deployed for massive scale-up and rapid diagnosis of SARS-CoV-2 infection, particularly in low-resource settings. [ABSTRACT FROM AUTHOR]

A fundamental understanding of the process parameters affecting the catalytic hydrodeoxygenation (HDO) of bio-oils is of significance for enabling further progression and improvement of industrial biofuel upgrading methods. Herein, a novel demonstration and evaluation of the effect of temperature, pressure, and weight hourly space velocity in the continuous HDO of vanillin to cresol over a Ni-Mo/δ-Al2O3 catalyst are presented. Response surface methodology was used as a statistical experimental design method, and the application of central composite design enabled the generation of a statistically significant simulation model and a true optimization parametric study. The distribution of Ni and Mo on δ-Al2O3 was confirmed using scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX). No gradients with EDX mapping could be identified, and the elemental analysis showed well-dispersion of the metals. The mesoporous character of the catalyst-support system was unraveled using N2 physisorption. Experiments were conducted within the parametric range of 250–350 °C, 3–9 bar, and 15–35 h−1. Both temperature and pressure were found to have statistically significant linear and quadratic effects on the selectivity for cresol. The parametric interaction of temperature with pressure and space velocity also had a significant effect on the resulting response. The optimal temperature range becomes more critical at lower space velocities. Optimal selectivity for cresol was established at 314 °C, 5 bar, and 35 h−1. The fitting quality of the generated regression model was statistically confirmed and experimentally validated to describe the specified HDO process within the 95% two-sided confidence interval. [ABSTRACT FROM AUTHOR]

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In this study, stir bar sorptive extraction as an easy to use, solventless, and novel sample enrichment technique combined with thermal desorption (TD)-gas chromatography triple quadrupole mass spectrometry (GC-MS/MS) was applied to determine cresols in wastewater samples for the first time. The analytical method is based on effortless extraction followed by TD-GC-MS/MS detection not requiring derivatization. The design of experiment procedure was utilized for improved extraction and analytical conditions. In this regard, the major sample extraction parameters (extraction time, salt addition, methanol content, pH, and stirring rate) and TD parameters (desorption flow, desorption temperature, desorption time, and cryo-focusing inlet temperature) were scrutinized and optimized. The fractional factorial design showed that stirring rate, extraction time, and methanol content were the major influential factors for extraction. While desorption flow, desorption temperature, and cryo-focusing inlet temperature significantly affected the instrumental analysis conditions. The optimized methodological conditions for the stir bar coated with polydimethylsiloxane were as follows: sample volume of 20 mL, methanol addition of 10%, stirring rate of 1200 rpm, desorption time of 10 min, desorption temperature of 240°C, desorption flow of 20 mL/min, and cryo-focusing inlet temperature of ‒20°C. The analytical characteristic of the proposed methodology presents good linearity (0.9909–0.9918), repeatability (11.5–15.1%), recovery (104.78 ± 0.27 to 106.19 ± 0.16%), and low detection limits (0.020–0.04 ng/mL). The established method was employed to measure trace levels of cresols in several wastewater samples taken from Istanbul. [ABSTRACT FROM AUTHOR]

The present study aims to explore the role of characterized hydrocarbons in thermally cracked shell liquid in determining its overall fuel properties and combustion characteristics in a CI engine. For this purpose, waste shell liquid was extracted from waste cashew nut shell by means of cold extraction technique using a simple electrically operated mechanical screw press, which reported maximum extractable oil content as 17.7 %. In addition, it was thermally cracked at 350-400 °C using conventional heating for both lab-scale and pilot-scale extraction. Based on its chemical composition, raw shell liquid contained anacardic acid and cardol, while thermally cracked shell liquid had cresol and methyl oleate as their dominant hydrocarbon compounds. Their composition was found to be 51.84 %, 33.68 %, 43.87 %, and 28.49 %, respectively. According to their contribution, both cyclic and aromatic as well as linear-chained hydrocarbons exhibited significant effect on the fuel properties of the cracked shell liquid, with carbon atoms contributing to its physical and thermal properties, whereas cyclic and aromatic hydrocarbons enhance its flow characteristics. Next, neat and blend samples of this cracked shell liquid with petro diesel reported higher peak in-cylinder pressure by 5.6 % (on average) due to the presence of fatty acid esters, which induced early ignition and provided sufficient time for combustion. Meanwhile, higher emission levels were attributed by both cyclic and aromatic and linear-chained hydrocarbons, citing aromaticity and unsaturation in their molecules, which also resulted in reduced thermal efficiencies by 12.5 % (on average), upon accounting for their inferior calorific content. In conclusion, it is evident that hydrocarbons in these treated shell liquids play a significant role in their fuel properties and engine characteristics.

Orthorhombic molybdenum trioxide (α-MoO3) is well known as a photocatalyst, adsorbent, and inhibitor during methyl orange photocatalytic degradation via TiO2. Therefore, besides the latter, other active photocatalysts, such as AgBr, ZnO, BiOI, and Cu2O, were assessed via the degradation of methyl orange and phenol in the presence of α-MoO3 using UV-A- and visible-light irradiation. Even though α-MoO3 could be used as a visible-light-driven photocatalyst, our results demonstrated that its presence in the reaction medium strongly inhibits the photocatalytic activity of TiO2, BiOI, Cu2O, and ZnO, while only the activity AgBr is not affected. Therefore, α-MoO3 might be an effective and stable inhibitor for photocatalytic processes to evaluate the newly explored photocatalysts. Quenching the photocatalytic reactions can offer information about the reaction mechanism. Moreover, the absence of photocatalytic inhibition suggests that besides photocatalytic processes, parallel reactions take place. [ABSTRACT FROM AUTHOR]

The biological synthesis of nanoparticles with copper, silver, and zinc (Cu, Ag, Zn) is reported in this study, adopting a greener, safe, reliable, and eco-friendly approach by using an aqueous leaf extract of Catharanthus roseus. The synthesised trimetallic nanoparticles were characterised using different characterisation techniques. The UV–visible spectroscopic technique was initially used to assess nanoparticle formation, in which absorption bands were observed at 220, 270, and 370 nm for Cu, Zn, and Ag nanocomposites, respectively. XRD revealed that the average crystalline size of the nanocomposites was 34.67 nm. The roles of reducing and capping/stabilising agents in the synthesis of Cu/Ag/Zn nanoparticles were confirmed by FTIR analysis, and the successful biosynthesis of the same was also confirmed by X-ray energy-dispersive spectroscopy (EDX) analysis. Potential applications of these synthesised trimetallic nanoparticles were evaluated by assessing their antioxidant and catalytic dye degradation activities. The antioxidant activity of the synthesised nanomaterial was studied using the DPPH assay. The catalytic breakdown of the harmful dyes phenol red and eosin yellow was examined using NaBH4 as a reducing agent. The results showed that the nanomaterial's radical scavenging capacity at 1000 ug/mL was 75.76% and the degradation of these dyes was up to 78% in the presence of NaBH4. Furthermore, the biogenic trimetallic nanomaterial exhibited effective catalytic degradation activity against methyl red and phenol red dyes. [ABSTRACT FROM AUTHOR]

In this work, flower-like β-Ni(OH)2 nanoarchitectonic particles were successfully synthesized via a simple homogeneous precipitation method. The crystal structure and morphology were detected by x-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The influence of the dosage of β-Ni(OH)2 and potassium persulfate (PS) on adsorption and degradation of cresol red dye was studied. The results indicate that when the dosage of β-Ni(OH)2 was larger than 5 g/L, the major reason for cresol red dye removal was adsorption due to its large specific surface area of 45 m2/g. However, when the dosage of β-Ni(OH)2 was 0.5–0.7 g/L, the adsorption effect on cresol red dye was not obvious, but the degradation effect became significant after adding 0.3–0.5 mmol/L PS, benefiting from the strong activation of PS to generate ·SO4−, ·OH− and S2O8− radicals by β-Ni(OH)2. The degradation efficiency of 0.1 mmol/L cresol red dye reached over 98% in a neutral or alkaline medium. In particular, at pH = 9, the initial degradation efficiency was 99.9% and remained 99.25% after eight cycles. Thus, the high activity and stability make β-Ni(OH)2 a promising catalyst for activating persulfate to degrade organic pollutants. [ABSTRACT FROM AUTHOR]

This study aims to enhance the energy use of two products of industry — Queen Palm residue and kraft lignin (KF) — through the combination of two technologies — briquetting and slow pyrolysis. The addition of 20% KF provided briquettes with higher physical, energy, and mechanical properties. The yields of the pyrolysis products were affected by both the pyrolysis temperature and the addition of KF. In the bio-oil, the presence of phenols, methyl phenols, and methoxy phenols was highlighted; these compounds were present in greater quantities in the treatments with KF. It is concluded that combining the briquetting and pyrolysis processes produces both energy and economic benefits because it is possible to transport lighter loads with the same amount of energy per volume. Under the briquetting conditions adopted in this study, the addition of KF as a binder is necessary because this results in briquettes with better physical, energy and mechanical properties. [ABSTRACT FROM AUTHOR]

O objetivo deste artigo é analisar as relações entre as ações estratégicas de uma cooperativa de crédito rural e as práticas de gestão nas dimensões econômicas, sociais e ambientais da sustentabilidade, por meio do uso dos critérios do Triple Bottom Line (TBL) e de conceitos e práticas relacionados ao cooperativismo de crédito. Quanto à metodologia, esta pesquisa caracteriza-se como estudo de caso único, com natureza aplicada com abordagem qualitativa com técnicas de análise quantitativa. Os resultados evidenciam que a cooperativa analisada do interior do estado do Paraná, não possui equilíbrio nos pilares econômico, social e ambiental para que se tenha vantagem competitiva para com a sustentabilidade organizacional.

The mechanism of adsorption of p-cresol over activated carbon adsorbent and the specific role of oxygen functional groups on cresol adsorption were studied using density functional theory (DFT) calculations. All the energy calculations and geometry optimization pertaining to DFT calculations were done using the B3LYP hybrid functional at basis set 6-31g level of theory in a dielectric medium of ε = 80 (corresponding to water). The interaction of cresol with different activated carbon models, namely pristine activated carbon, hydroxyl functionalized activated carbon, carbonyl functionalized activated carbon, and carboxyl functionalized activated carbon, were considered, and their adsorption energies corresponded to −416.47 kJ/mol, −54.73 kJ/mol, −49.99 kJ/mol, and −63.62 kJ/mol, respectively. The high adsorption energies suggested the chemisorptive nature of the cresol-activated carbon adsorption process. Among the oxygen functional groups, the carboxyl group tended to influence the adsorption process more than the hydroxyl and carbonyl groups, attributing to the formation of two types of hydrogen bonds between the carboxyl activated carbon and the cresol simultaneously. The outcomes of this study may provide valuable insights for future directions to design activated carbon with improved performance towards cresol adsorption.

The construction of highly efficient and selective hydrodeoxygenation (HDO) catalysts is of great significance for upgrading pyrolysis oil. In this work, nickel and iron-based NiFe(x)/FLRC-TiO 2 catalysts with a flower-like radial channel structure were successfully fabricated with a facile strategy. The effects of Ni/Fe molar ratios and operation conditions on the structure, morphology and HDO performance were investigated using p -cresol as model compound. Impressively, the NiFe(x)/FLRC-TiO 2 catalysts exhibit a well-defined radial channel structure with an average pore diameter of 27.4 nm and the NiFe(5)/FLRC-TiO 2 with appropriate Ni/Fe ratio of 5 exhibits the best HDO performance. Under the conditions of T=275 °C, p=3 MPa, and t=2.5, the conversion rate of p -cresol and the selectivity to the target product MCH reaches 100 % and 97.8 %, respectively, which supresses most of the reported Ni based catalysts. Combining with the structure and morphology charateriazation results, this excellent HDO performance could be ascribed to: (a) the unique flower-like radial channel structure of the catalysts stemmed from FLRC-TiO 2 provides more exposed active sites for HDO and fast mass transfer; (b) an appropriate Ni/Fe ratio contributes to the increase of specific surface area and pore volume of the catalyst, which boots the higher catalytic HDO activity; (c) the addition of Fe enhances acidity of catalyst and promotes the hydrodehydration of C–OH to target product MCH, together with the synergistic effect of FeNi metal sites, favoring the higher catalytic HDO activity. The proposed strategy for the preparation of radial channel structure FLRC-TiO 2 support can be extended to various other reactions. • The incorperation of Fe contributes to fast mass transfer. • FLRC-TiO 2 provides the catalysts more exposed active sites. • Synergistic effect between Fe and Ni promotes the removal of C-OH. [ABSTRACT FROM AUTHOR]

Optical properties of a synthetic dye cresol red (CR) were investigated at its absorption band maxima (λ max) using double beam scanning UV/VIS spectrophotometer for the sample solutions having initial optimized dye-concentration. Urbach Edge method was utilized for the investigations of absorption edge ( A E = 2.35 eV) while Mott and Davis model was utilized for the investigations of band gap energy for direct ( E g , direct = 2.45 eV) and indirect ( E g , indirect = 2.23 eV) allowed transitions. The spectrophotometric-evaluations assisted most-sensitive working pH of sample solutions was optimized for a long spectrum of pH values from 1 to 12 for further investigations. Some spectrophotometric and comercial parameters e.g., molar extinction coefficient ε , stability, reproducibility and fading were figured out. The response efficacy was also observed to enhanc the sensitivity and stability of the CR solutions by incorporating a selected amount (by %vol) of a polar additive ethanol. The invariant aborbance related isosbestic wavelength for both acidic and alkaline samples remained unaffected from pH and firmly stood at 475 nm. The improved and reasonable pH values were found to be pH 4 and pH 9 and hence were opted for CR solutions and may further be applicable to the radiation-induced degradation phenomenon based on radiolytic bleaching. [ABSTRACT FROM AUTHOR]

[Display omitted] • g-C 3 N 4 synthesized by microwave, thermal and solvothermal methods. • Morphology and surface area changed by changing synthesis method. • Sheets obtained by thermal, particles obtained by solvothermal and nanofibers by microwave method. • Microwave prepared g-C 3 N 4 has the highest photocatalytic activity for phenol and MO degradation. Graphitic carbon nitride (g-C 3 N 4) nanomaterials have been eco-friendly synthesized using microwave and compared to the materials prepared by conventional thermal and solvothermal methods. The properties of as-synthesized g-C 3 N 4 nanomaterials were investigated by various techniques. The results demonstrated the successful synthesis of g-C 3 N 4 either by conventional or microwave methods. However, morphology and surface area have been changed by changing the method used. While small sheets were obtained using thermal decomposition of melamine for 4 hrs. at 500 °C, and irregular particles were obtained from the solvothermal synthesis by heating melamine and cyanuric chloride for 16 hrs. at 180 °C, nanofibers structure with the largest surface area was obtained by microwave irradiation of melamine and cyanuric chloride for 1hr. The photocatalytic performance of the synthesized materials has been assessed for the decomposition of phenol and methyl orange (MO) dye. All prepared g-C 3 N 4 materials have shown better solar light photocatalytic performance compared to TiO 2 nanoparticles. This has been directly correlated to the narrower band gab energies of g-C 3 N 4 materials (E g(TGCN) = 2.8 eV, E g(SGCN) = 2.4 eV, E g(MGCN) = 2.45 eV) compared to TiO 2 (3.1 eV). Moreover, the photocatalytic activity of microwave prepared g-C 3 N 4 (MGCN) is about 2 times higher than those prepared by the other methods (TGCN & SGCN) and ∼ 7 times higher than that of TiO 2. This can be readily related to the modified fibrous structure and the highest surface area of MGCN (31.84 m2/g) compared to other materials. [ABSTRACT FROM AUTHOR]

• The yield of cresol is 49.1 % by PG8@MOF catalysis and the ratio of o -/ p -isomer reaches 5:1. • MOF-199 promotes contact between PG8@MOF and toluene. • The optimal catalysts exhibited excellent reusability in the direct hydroxylation of toluene. The activation of aromatic Csp2-H bonds to achieve hydroxylation of aromatics has attracted widespread attention, but it remains a huge challenge. Therefore, developing a durable and efficient catalyst for selective hydroxylation of toluene is an important issue. This article synthesized MOF-199 using phthalic acid as a ligand and synthesized it using impregnation method PG8@MOF Catalysts. The experimental results indicate that, PG8@MOF In the hydroxylation reaction of toluene, it has strong advantages. Under the optimal conditions, the yield of cresol is 49.1 %, among which the yield of ortho cresol reaches 41.1 %. The regenerated catalyst has good reusability. These findings provide a convenient method for constructing highly active catalysts for direct hydroxylation of toluene. [Display omitted] [ABSTRACT FROM AUTHOR]

In the fight against fermentation-disrupting bacteriophages, UV-C irradiation is promising due to its capability of damaging nucleic acids and preventing organisms to replicate. The purpose of this study is to investigate the effect of this radiation on whey using three different devices (lab-/technical-scale, batch/continuous) and UV-C doses between 0.4 and 100 J mL−1. In vitro toxicity assays (Comet, WST-1, Ames) proved that irradiated whey does not exhibit any genotoxic, cytotoxic, or mutagenic activity and is presumed to be harmless to health. However, the irradiated product had an intense "cowish/stable-like/manure-like" off-flavor, which was identified as para- cresol by GC-MS-O. Riboflavin decay was observed as well as decreases in cystine and aromatic amino acids, whose degradation products are known to be odor-active. With our current data, we are not able to define a suitable process window or to recommend the application of this technology to treat whey. [ABSTRACT FROM AUTHOR]

Introduction. The increase in production volumes and the expansion of the scope of application of polyvinyl chloride (PVC) compounds contributes to the development of new additives and the attraction of new sources of raw materials for their production. The most important additives necessary for processing PVC are plasticizers. Plasticizers market is one of the largest segments of the global additives market. Since plasticizers are the most simple, cheap and affordable way to modify various properties of the polymeric compositions, their role in processing polymeric materials has recently increased significantly. In application the ester plasticizers, capable to plasticize almost all polymers, especially polyvinylchloride are considered as the most practical. Currently, the industry has mastered production of more than three hundred brands of plasticizers, most of which are esters of phthalic acid. Traditional phthalate plasticizers are the most widely used all over the world. Materials and methods. The paper describes the esterification reactions of phthalic anhydride with oxyethylated (degree of oxyethylation 1.2) and oxypropylated (degree of oxypropelation 1.1) cresols. New symmetric and asymmetric phthalate plasticizers were obtained – dikresoxycresylphthalate, butoxyethylcreoxyethylphthalate, cresylcresoxyethylphthalate and cresylcresoxypropylphthalate, optimum conditions for their preparationare picked up, studied their physical and chemical properties. The obtained experimental data were used to identify promising new phthalate-type plasticizers by the method of cluster analysis. Cluster analysis is the most effective method for solving this problem, because it is intended for combining some samples into classes (clusters) in such a way that the most similar in properties fall into one cluster, but at the same time the samples of different clusters differ as much as possible from each other. Clustering was carried out using the Statistica 10 program. Since at present the reference plasticizer is dioctylphthalate (DOP), the test results of the samples were compared with those of PVC compositions containing DOP. Results and discussions. According to the data obtained, it was found that butoxyethylcreoxyethyl phthalate has the best characteristics in terms of plasticizing ability. The influence of the selected plasticizer on the technological characteristics of PVC-compounds has been studied. The efficiency of the synthesized butoxyethylcreoxyethylphthalate in the PVC composition was evaluated by the indicator (index) of melt flow rate (MFR) and by the indicators of “thermal stability” and “color stability”. Conclusion. Use of the developed additive contributes to the production of PVC compounds with improved rheological characteristics, increased heat resistance and color stability.

Gold nanoparticles on the surface of cerium(IV) oxide were obtained by photochemical reduction of HAuCl4 in water–alcohol solutions. The spectral characteristics of the resultant nanocomposites, their phase composition and morphology, and the kinetics of the gold particles formation were examined depending on the nature of the monohydric alcohol and on the morphology of the cerium(IV) oxide particles. The catalytic activity of cerium(IV) oxide before and after modification with gold nanoparticles in the reactions of photodegradation of methyl orange and phenol was studied. It was shown that the CeO2 particles modified with gold nanoparticles upon irradiation with UV light have the highest photocatalytic activity. [ABSTRACT FROM AUTHOR]

BACKGROUND: The development of efficient synthetic pathways for bio‐based chemicals is beneficial to sustainable development of the chemical industry. However, directional production of phenolic chemicals using lignocellulose remains a challenging issue, because the reaction paths as well as intermediates in the catalytic transformation of lignocellulose are often complicated. RESULTS: Bio‐based cresol can be selectively prepared from lignocellulose biomass. This steerable transformation has been achieved by lignocellulose catalytic pyrolysis to aromatic intermediates over a magnetic oxide‐modified zeolite catalyst (Fe3O4@HZSM‐5) and intermediate hydroxylation to cresol over a metal–organic framework catalyst (Cu‐MOF). Based on the analysis of intermediates and on catalyst characterization, the corresponding reaction pathways are put forward. Using the Cu‐MOF catalyst, the highest selectivity of cresol (81.5%) and the highest conversion (76.8%) were gained at 40 °C in 4 h. CONCLUSIONS: The work presented proves that an important phenolic chemical (cresol) can be selectively prepared from lignocellulose raw materials. The Cu‐MOF catalyst shows superior performance and good reusability in the bio‐cresol synthesis. Reactive oxygen species take a prominent role in the cresol synthesis. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The mechanism of adsorption of p-cresol over activated carbon adsorbent and the specific role of oxygen functional groups on cresol adsorption were studied using density functional theory (DFT) calculations. All the energy calculations and geometry optimization pertaining to DFT calculations were done using the B3LYP hybrid functional at basis set 6-31g level of theory in a dielectric medium of ε = 80 (corresponding to water). The interaction of cresol with different activated carbon models, namely pristine activated carbon, hydroxyl functionalized activated carbon, carbonyl functionalized activated carbon, and carboxyl functionalized activated carbon, were considered, and their adsorption energies corresponded to −416.47 kJ/mol, −54.73 kJ/mol, −49.99 kJ/mol, and −63.62 kJ/mol, respectively. The high adsorption energies suggested the chemisorptive nature of the cresol-activated carbon adsorption process. Among the oxygen functional groups, the carboxyl group tended to influence the adsorption process more than the hydroxyl and carbonyl groups, attributing to the formation of two types of hydrogen bonds between the carboxyl activated carbon and the cresol simultaneously. The outcomes of this study may provide valuable insights for future directions to design activated carbon with improved performance towards cresol adsorption. [ABSTRACT FROM AUTHOR]

The innovative materials for the wastewater treatment have gained significant attention for the utilization to control environmental remediation. In the context, this study explores the fabrication and applications of Manganese doped molybdenum disulfide (Mn–MoS 2) with (0 %, 2 %, 3 %, 4 %, 5 %) concentrations by hydrothermal approach. This article highlights the successful incorporation of well-matched manganese (Mn+2) in base materials and evaluates their powers for the degradation of pharmaceutical phenol and methyl blue (MB) dye. The prepared nanostructures delve into various characterizations to study their structural, morphological, elemental, optical and electronic properties. The X-ray Diffraction (XRD) and Fourier-transform infrared Spectroscopy (FTIR) shed lights insight the structures. The Energy Dispersive X-ray Spectroscopy (EDX) and Scanning Electron Microscope (SEM) are used to showcase the imagery of elemental and morphological properties. The Zeta Potential examines the conductivity while Brunauer-Emmett-Teller (BET) is carried to determine the specific surface area. Additionally, Ultraviolet Visible Spectroscopy (UV) and Photoluminescence Spectroscopy (PL) elucidate the optical properties of the synthesized materials. The synergistic interplay between the dopant and host material MoS 2 resulted to effective degradation, integrating the potential of successful environmental remediation agent of Mn–MoS 2. [Display omitted] • This article presents an insights study of synthesis and novel dual applications. • This study unveils interplay of synergistic approach. • The enhanced 65 % outcome are perceived for novel phenol degradation. • The potent behavior of nanostructures against methyl blue dye accesed. [ABSTRACT FROM AUTHOR]

The anion photoelectron spectra of ortho-, meta-, and para-methylphenoxide, as well as methyl deprotonated meta-methylphenol, were measured. Using the Slow Electron Velocity Map Imaging technique, the Electron Affinities (EAs) of the o-, m-, and p-methylphenoxyl radicals were measured as follows: 2.1991 ± 0.0014, 2.2177 ± 0.0014, and 2.1199 ± 0.0014 eV, respectively. The EA of m-methylenephenol was also obtained, 1.024 ± 0.008 eV. In all four cases, the dominant vibrational progressions observed are due to several ring distortion vibrational normal modes that were activated upon photodetachment, leading to vibrational progressions spaced by ~500 cm-1. Using the methylphenol O–H bond dissociation energies reported by King et al. and revised by Karsili et al., a thermodynamic cycle was constructed and the acidities of the methylphenol isomers were determined as follows: ΔacidH298K0 = 348.39 ± 0.25, 348.82 ± 0.25, 350.08 ± 0.25, and 349.60 ± 0.25 kcal/mol for cis-ortho-, trans-ortho-, m-, and p-methylphenol, respectively. The excitation energies for the ground doublet state to the lowest excited doublet state electronic transition in o-, m-, and p-methylphenoxyl were also measured as follows: 1.029 ± 0.009, 0.962 ± 0.002, and 1.029 ± 0.009 eV, respectively. In the photoelectron spectra of the neutral excited states, C–O stretching modes were excited in addition to ring distortion modes. Electron autodetachment was observed in the cases of both m- and p-methylphenoxide, with the para isomer showing a lower photon energy onset for this phenomenon. [ABSTRACT FROM AUTHOR]

This study clarifies the mechanism behind the isomerization of cresol, focusing on a shaped cerium-modified Beta zeolite. The catalysts were characterized using a series of characterization techniques, including XRD, Py-IR, XPS, and TGA. The results emphasize the pivotal role of cerium, particularly at a 5 % modification concentration, in improving catalyst acidity. The mechanism of isomerization is revealed through kinetic calculation of reversible monomolecular systems, emphasizing the significance of acid sites. TGA analysis of catalyst deactivation reveals distinctive carbon deposition patterns, with the cerium-modified zeolite displaying enhanced resistance to pore blockage through Type II carbon deposition. XPS analysis post-deactivation indicates an increased proportion of Ce3+, suggesting elevated oxygen vacancies and unsaturated chemical bonds, influencing the catalytic activity negatively. In summary, an appropriate cerium modification, especially at the 5 % concentration, strikes a balance between enhanced acidity and resistance to carbon deposition, providing valuable insights for tailoring zeolite catalysts in cresol isomerization. [Display omitted] • Discovered a catalyst for cresol isomerization and determined the optimal metal Ce modification concentration. • It was determined that Brønsted acid played a positive role in the reaction. • According to the kinetic calculation results, the basic process of the isomerization reaction was verified. [ABSTRACT FROM AUTHOR]

• Cresols have negative effects on the environment and the viability of aquatic organisms. • In this work, HDESs were used to extract m-cresol and o-cresol from wastewater. • Six terpene and carboxylic acid based HDES were synthesized and characterized. • An extraction efficiency higher than 94 % was achieved with all prepared HDESs. • The effect of various parameters on the extraction efficiency of HDESs was investigated. [Display omitted] Cresols have distinct effects on the environment and human health. For example, o-cresol is considered a toxic isomer and can cause serious health problems. Cresol isomers generally have a negative impact on the environment as they can be hazardous to aquatic life and can accumulate in the food chain. The introduction of these chemicals has the potential to disrupt the balance of ecological systems by reducing oxygen concentrations in aqueous environments, thus affecting the viability and reproductive capacity of aquatic organisms. This work involves the use of six hydrophobic deep eutectic solvents (HDESs) for the extraction of m-cresol and o-cresol from wastewater. The HDESs include menthol:thymol, menthol:decanoic acid, thymol:decanoic acid, hydrocinnamic acid:decanoic acid, thymol:coumarin and thymol:camphor. All HDESs were prepared in a molar ratio of 1:1. The effects of various parameters such as contact time, mass ratio of HDESs to water, molar ratio of HDESs and initial concentration were investigated. The experimental results indicate excellent efficiency in the removal of cresols from wastewater using all HDESs. The extraction efficiency of > 94 % was achieved for the removal of cresol isomers from wastewater using all prepared HDESs. In addition, COSMO-RS was used to understand the extraction process. [ABSTRACT FROM AUTHOR]

Understanding the hydrodeoxygenation (HDO) mechanism of phenolic compounds is crucial for advancing catalytic upgrading techniques of bio-oil. Herein, a comprehensive theoretical study of the HDO of lignin-derived phenolic compounds (phenol, cresols, and guaiacol) on the MoS 2 surface was carried out using periodic density functional theory (DFT) calculations. Adsorption of phenolic compounds on different crystal faces was first compared. The MoS 2 (100) crystal face is more favorable for the adsorption of phenolic compounds which show the horizontal adsorption configurations. Three kinds of HDO patterns were explored for the phenolic compounds. Phenol tends to transform into benzene via stepwise deoxygenation and hydrogenation under the induction of active hydrogen. For cresol isomers, their HDO mechanisms differ from each other due to the influence of the methyl group on the dehydroxylation process. Specifically, o -cresol follows a synergistic process of deoxidation and hydrogenation, m -cresol undergoes a two-step reaction involving direct dehydroxylation and hydrogenation, and p -cresol involves the identical HDO pathway as phenol. With regard to guaiacol, the preferred HDO route involves successive dehydroxylation and demethoxylation to benzene with the anisole intermediate. In addition, the adsorption of phenolics over transition metal-doped MoS 2 catalysts was further explored to examine the potential of metal doping for the HDO of phenolics. The doping of Ta and W increases the adsorption capacity, which shows the potential to enhance the HDO activity of the catalyst theoretically. [Display omitted] • The MoS 2 (100) plane with M-edge is favorable for phenol adsorption. • A two-step deoxygenation and hydrogenation process is preferred for phenol HDO. • Methyl and its position affect the competitiveness of the cresol HDO pathways. • The HDO of guaiacol prefers successive dehydroxylation and demethoxylation. • Potential metal-doped MoS 2 catalysts are determined based on adsorption energy. [ABSTRACT FROM AUTHOR]

Catalyst deactivation and shape selectivity in evolved products and retained coke are studied on medium, large and extra-large pore zeolites with varying Si/Al ratios in the disproportionation of anisole. Deactivation modelling as a function of time on stream highlights the key role of the catalyst pore volume. Changes in selectivity between the primary (methylanisole) and secondary (cresol) products are due to the overtaking of one path over a second for the production of cresol. The nature of the products (methyl phenols) inhibits the formation of "usual" polyaromatic and non-oxygenated coke via the Sullivan mechanism, leaving only adsorbed oxygenated monoaromatics, available for transalkylation reactions with the feed, having adsorbed and fouled most of the available surface in the catalyst channels. [Display omitted] • Pore shape and size has not impact on coke nature for anisole disproportionation. • MOR, FAU, *BEA and JZO zeolites yield to the same oxygenated coke molecules: methyl-phenolics. • Phenolic function blocks the ring contraction/expansion mechanism responsible for coke growth. • Deactivation is by fouling and depends mainly on the pore volume and channel interconnectivity. [ABSTRACT FROM AUTHOR]

Catalytic fast pyrolysis of biomass is a promising technology to generate biofuel blendstocks. This process generates a carbon-rich wastewater, which represents a loss of carbon that could be converted to co-products. Here, we explored the biological conversion of methyl phenols (cresols), a major component of biomass pyrolysis wastewater, into 2-methyl and 3-methyl muconic acids for use as polymer building blocks and plasticizers. We engineered Pseudomonas putida KT2440 to convert all three cresol isomers, o-, m-, and p-cresol, into their methyl muconic acid counterparts via the heterologous aromatic hydroxylase DmpKLMNOP from Pseudomonas putida CF600. We optimized conversion of cresols by expressing a heterologous (methyl)catechol dioxygenase ClcA from Rhodococcus opacus 1CP, followed by proof-of-concept fed-batch bioreactor cultivations. Methyl muconic acids and the hydrogenated methyl adipic acids were incorporated into nylons and plasticizers to evaluate potential performance advantages relative to existing materials. Methyl muconic acids in nylon-6,6 analogs substantially reduced melting and glass transition temperatures and enable post-polymerization modifications, and incorporating methyl adipic acid into nylon-6,6 analogs leads to a slightly reduced glass transition temperature and a 12% reduction in water permeability relative to nylon-6,6. When methyl diacids were incorporated into plasticizers for poly(vinyl chloride), they exhibit lower glass transition temperatures at the same mass loadings as phthalic acid and adipic acid-based plasticizers. The methyl diacids were also predicted to exhibit reduced health and environmental risks compared to phthalic acid. Overall, this study encompasses the selection of a target product from an exemplary waste stream to the demonstration of multiple industrially relevant performance advantages relative to petroleum-derived analogs and highlights the potential for biological waste stream valorization. [ABSTRACT FROM AUTHOR]

Methyl-hydroxy-cyclohexadienyl radicals (OTAs) are the key products of the photooxidation of toluene, with implications for the fate of toluene. Hence, we investigated the photooxidation mechanisms and kinetics of three main OTAs (o -OTA, m -OTA, and p -OTA) with NO 2 using quantum chemical calculations as well as the fate of OTAs under the different concentration ratios of NO 2 and O 2. The mechanism results show that the pathway of H-abstraction by NO 2 to anti-HONO (anti-H-abstraction) is more favorable than the syn-H-abstraction pathway, because the strong interaction between OTAs and NO 2 is formed in the transition states of the anti-H-abstraction pathways. The branching ratios of the anti-H-abstraction pathways are more than 99% in the temperature range of 216−298 K. The total rate constant of the OTA-NO 2 reaction is 9.9 × 10−12 cm3/(molecule∙sec) at 298 K, which is contributed about 90% by o -OTA + NO 2 , and the main products are o -cresol and anti-HONO. The half-lives of the OTA-NO 2 reaction in some polluted areas of China are 35 times longer than those of the OTA-O 2 reaction. In the atmosphere, the NO 2 - and O 2 - initiated reactions of OTAs have the same ability to form cresols as [NO 2 ] is up to 142.1 ppmV, which is impossible to achieve. It implies that under the experimental condition, the [NO 2 ]/[O 2 ] should be controlled to be less than 7.8 × 10−5 to simulate real atmospheric oxidation of toluene. Our results reveal that for the photooxidation of toluene, the yield of cresol is not affected by the concentration of NO 2 under the atmospheric environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Co-biodegradation of phenol and cresols in binary and ternary mixtures was investigated in circulating packed-bed bioreactors (CPPBs). Effects of composition (phenol: 500 mg L−1, o-cresol and p-cresol: 100–500 mg L−1), phenolic loading rate (2–508 mg L−1 h−1), and bioreactor residence time (1–54 h) on the removal efficiency and removal rate of phenols and effluent toxicity were evaluated. In the binary mixtures, maximum phenol removal rate with 100, 300, and 500 mg L−1 p-cresol was 87.2, 89.2, and 90.7 mg L−1 h−1 at residence times of 4.0, 3.6, and 2.7 h, respectively. The corresponding values with o-cresol were 117.7, 76.6, and 68.9 mg L−1 h−1 at residence times of 4.2, 4.6, and 4.4 h. Increase of p-cresol or o-cresol concentration in the binary mixture with phenol enhanced the cresol removal rate, with the highest removal rates for p-cresol and o-cresol being 121.3 and 70.3 mg L−1 h−1, respectively. In the ternary mixture, increase of p-cresol or o-cresol concentration enhanced their removal rate and presence of each compound inhibited the biodegradation of the other. Cresols, specially o-cresol, impacted the biodegradation of phenol negatively. Consistent with the trend for biodegradation of individual phenols, the highest removal rate was achieved with p-cresol, followed by phenol, and o-cresol (135.3, 129.2, and 108.0 mg L−1 h−1). Effluents were less toxic than the influents, but the toxicity was not eliminated in the effluents obtained under maximum removal rate of phenolic compounds. This implies that removal efficiency is more influential than removal rate in eliminating the toxicity. [ABSTRACT FROM AUTHOR]

With the tremendous prosperity of industry, more and more hazardous waste is discharged from industrial production processes. Cresol distillation residue is a typical industrial hazardous waste that causes severe pollution without proper treatment. Herein, the co-pyrolysis of rice husk and cresol distillation residue was studied using thermogravimetry–mass spectrometry and kinetic studies. The Coats and Redfern method was employed to calculate the activation energy. The results indicated that the pyrolysis process of cresol distillation residue and RH/CDR (Rice Husk and Cresol Distillation Residue) blends can be divided into four stages and three stages for RH. The introduction of RH not only improved the thermo-stability of cresol distillation residue at a low temperature but also reduced the activation energy of the blends. The activation energy was the lowest when the proportion of rice husk in the blend was 60%. The main gaseous pyrolysis products included CH4, H2O, C2H2, CO2, C3H6 and H2. There existed an unusual combination of synergistic and inhibitive interactions between RH and cresol distillation residue, respectively, within different temperature ranges. The synergistic interaction decreased the reaction's activation energy, whereas the inhibitive interaction reduced the emission of main gaseous products, such as CH4 and CO2. It was concluded that the addition of RH was conducive to improving the pyrolytic performance of cresol distillation residue and the resource utilization of cresol distillation residue. [ABSTRACT FROM AUTHOR]

Diphenylmethyl (DPM) is a carboxyl protecting group which is often used in the synthesis of β-lactam antibiotics and there are many methods for its removal in industrial production. We have developed a continuous flow method to remove it for β-lactam antibiotics using cresol in microreactor. The method is a more efficient, faster and higher-yield method for removing DPM, which has been tested in several marketed β-lactam antibiotics. [ABSTRACT FROM AUTHOR]

A cyclodextrin-based polymer was prepared by crosslinking β-cyclodextrin with epichlorohydrin to be assessed as a sorbent material for cresols in packed-bed columns. Both Langmuir and Freundlich isotherms were appropriate to describe the sorption equilibrium in the conditions tested, and the thermodynamic parameters obtained for this process confirmed its exothermic nature with similar enthalpies (between − 6.8 and − 8.3 kJ/mol) for the three isomers. The removal of cresols from water was carried out in nine cycles of sorption–desorption in fixed-column experiments with the cyclodextrin hydrogel, achieving sorption capacities of 6.2, 11.6, and 15.1 mg/g for o-, m-, p-cresol, respectively. These differences in sorption capacities are due to the different chemical structures of cresols, that is, the relative position of the methyl and hydroxyl groups. However, similar sorption rates were observed for each isomer, with a mean value of 0.10 mg-cresol g-CDP–1 min–1 in all cases. The experimental data for the breakthrough and the elution curves have been successfully modeled by two effective two-parameter equations, a dose–response model for the sorption step and a pulse-peak model for the regeneration step. The cyclodextrin polymer matrix has been proven to be an effective a good sorbent material for removing cresols from water, exhibiting remarkable reusability performance and structural stability throughout the successive elution steps carried out with methanol. [ABSTRACT FROM AUTHOR]

Naomaohu lignite (NL) was extracted with isometric acetone/carbon disulfide mixed solvent under ultrasonic irradiation. The extraction residue (ER) was subjected to non‐catalytic hydroconversion (NCHC) and one/two‐step cascade catalytic hydroconversion (CHC) in n‐hexane at 300 °C under 4 MPa of H2 over magnetic solid superacid (MSSA) and superbase (MSSB). The NCHC‐soluble portion from the NCHC (SPNCHC) and CHC‐soluble portion from the one/two‐step cascade CHC (SPA, SPB, SPA‐B, and SPB‐A) were analyzed with a gas chromatograph/ mass spectrometer (GC/MS). The results show that the yields of SPA and SPB are 18.65 % and 16.31 %, respectively, which are much higher than that of SPNCHC (1.26 %). According to the analysis with GC/MS, SPA and SPB are rich in phenol, dimethylnaphthalene, cresol, trimethylphenols, and xylenols, while alkanes are the predominant group component in the SPNCHC, indicating that MSSA selectively catalyzed the cleavage of Car−Calk and Calk−O bridged bonds, whereas MSSB tended to cleave Car−O and Calk−O bridged bonds connecting some aromatic rings in the ER. The yield of SPB‐A was as high as 11.07 % and SPA‐B was only 0.59 %. The results showed that more soluble species in the ER could be further released through the cascade CHC procedures. Benzyloxybenzene was used as a coal‐related model compound to probe the possible mechanisms of one/two‐step cascade CHC of the ER. [ABSTRACT FROM AUTHOR]