Ratio Of Phenol Research Articles

Synthesis of a water‐soluble high hydroxymethyl content phenolic resin crosslinker and the associated polyacrylamide weak gel property investigation

AbstractAs an in‐depth profile control agent, water‐soluble phenolic resin crosslinking polyacrylamide weak gel has been widely used in the middle and high water cut stage of water flooding reservoir. In this study, the phenolic resin was synthesized by two‐step alkali catalysis. Factors influencing the synthesis of phenolic resin, including the molar ratio of phenol and formaldehyde, catalyst types, reaction time, were investigated with hydroxylmethyl and aldehyde content as the criterion. When the molar ratio of phenolic resin was 1:2 and NaOH was catalyst, at 80°C for 4 h, the phenolic resin had the highest hydroxymethyl content (49.37%) and the lowest free aldehyde content (2.95%). Weak gel was formed by the reaction of LT002‐polyacrylamide with phenolic resin. Taking the gelation time and strength as criteria, the factors influencing the crosslinking property, including hydroxymethyl content, crosslinker addition, and polyacrylamide concentration were investigated respectively. Under optimal formulation, the property investigation shows that the hydroxymethyl group in the phenolic resin can be crosslinked with the amide group in polyacrylamide, the gelation time is long (50–60 h), and the gelation strength is larger than 5 × 104 mPa s, which is conductive to the plugging of deep oil layers. When the permeability was 5061 × 10−3 μm2, the plugging rate was 72.73%.

High-Temperature-Resistant Profile Control System Formed by Hydrolyzed Polyacrylamide and Water-Soluble Phenol-Formaldehyde Resin.

To realize the effective profile control of a heavy oil reservoir, hydrolyzed polyacrylamide (HPAM) and water-soluble phenol-formaldehyde resin (PR) were chosen to prepare the profile control system, which gelled at medium or low temperatures and existed stably at high temperatures in the meantime. The effects of phenolic ratios, PR concentration, and HPAM concentration on the formation and strength of the gels were systematically studied by the gel-strength code method and rheological measurements. And the microstructure of the gels was investigated by scanning electron microscope measurements. The results showed that the gelling time of the HPAM-PR system was 13 h at 70 °C. The formed gel could stay stable for 90 days at 140 °C. In addition, the gels showed viscoelastic properties, and the viscosity reached 18,000 mPa·s under a 1.5 s-1 shearing rate due to their three-dimensional cellular network structure. The formation of the gels was attributable to the hydroxyl groups of the PR crosslinking agent, which could undergo the dehydration condensation reaction with amide groups under non-acidic conditions and form intermolecular crosslinking with HPAM molecules. And the organic crosslinker gel system could maintain stability at higher temperatures because covalent bonds formed between molecules.

Acquisition of para-(1-methylcyclopentyl)phenol and its acylation reaction with acetyl- and benzoyl chlorides

The article is devoted to the study of phenol cycloalkylation reactions 1-methylcyclopentene in a in periodical action installation in the presence of zeolite-containing catalyst KN-30 and acylation reactions of obtained p-(1-methylcyclopentyl)phenol with acetyl and benzoyl chlorides in the presence of a ZnCl2 catalyst. First of all, the influence kinetic parameters (temperature, time, molar ratios starting components, the amount of catalyst) on the yield and selectivity reactions of cycloalkylation of phenol with 1-methylcyclopentene in the presence of catalyst KN-30 was investigated. In the found optimal conditions for the cycloalkylation reaction: temperature – 110 оС, time – 5 hours, molar ratio of phenol to MCF 1:1, amount of catalyst 12 %, yield of the target product – p-(1-methylcyclopentyl)phenol is 77.3 % (based on phenol), the selectivity of the target product is 92.6 %. Acylation reactions of the obtained p-(1-methylcyclopentyl)phenol with acetyl- and benzoyl chlorides were performed in the presence of anhydrous catalyst ZnCl2. In order to obtain effective conditions for acylation reactions, the influence of the reaction temperature, duration, and molar ratio of the starting components on the yield and selectivity of methylcyclopentylaceto- and benzophenones was studied. As a result, it was found that for acylation reactions of p-(1-methylcyclopentyl)phenol with acetyl and benzoyl chloride in the presence of a ZnCl2 catalyst, the reaction temperature is 140–150 оC, the duration should be 35–40 minutes, and the molar ratio phenol AC(BC) should be 1:2. Under these conditions, the yield of target products is 57.2–61.7 % (based on the taken alkylphenol).

Wet-Spinning Preparation of High-Performance Phenol-Modified Melamine-Formaldehyde Fibers

In order to improve the toughness of melamine formaldehyde (MF) fibers, the modified fibers with varying synthesis mole ratios were fabricated through wet spinning utilizing melamine and paraformaldehyde as the primary constituents and phenol as the modifying agent. The structural characteristics and properties of the fibers were assessed and examined through Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and mechanical property evaluations. The results showed that the incorporation of phenol led to a significant enhancement in both the thermal stability and mechanical properties of the fibers. Specifically, when the mole ratio of melamine, phenol, and paraformaldehyde was 1:1:4 and the heat curing temperature was 180 °C, the fiber exhibited a breaking strength of 151 MPa and an elongation at break of 15.1%. This represented an increase in elongation at break of approximately 84% compared to the unmodified fiber without phenol. Furthermore, the thermal properties of the modified fibers were notably improved, as evidenced by an increase in char yield at 700 °C from 27.7% to 62.5%.

Wpływ napięcia międzyfazowego między ropą a wodą na stabilność emulsji ropnych

"The stability of crude oil emulsions sourced from wells in two distinct fields distinguished by varying physical-chemical properties was analysed. The oil taken from the wells of Muradkhanli and Balakhani fields of State Oil Company of the Azerbaijan Republic (SOCAR) has been used as the research object. Demulsification of both oils, whose composition differs in the amount of high molecular compounds, has been investigated through the static settling method for 2, 4, 6, 8, 10 and 12 hours, and the amount of residual water in the oil has been recorded. In the same time interval, the oils have been tested by adding n-hexane and phenol to them, respectively. During the experiments, it was discovered that after the addition of n-hexane, which is a saturated hydrocarbon, the surface tension force increased in both oil samples and caused the formation of water in the form of a dispersed phase in the oil, which resulted in an increase in stability. In particular, as the concentration of n-hexane in oil increased, oil emulsions became aggregative and kinetically stable. The experiments conducted involving the addition of phenol to oils revealed that an increase in the volume of phenol in the oil led to a decrease in the surface tension force at the oil-water boundary, thereby accelerating the demulsification process. Subsequently, the research extended to investigating the emulsion stability of the oil samples by adding phenol and n-hexane in varying proportions. It was observed that an increase in the phenol ratio expedited the demulsification process, whereas a higher hexane ratio weakened it. Throughout the experimental tests, fluctuations in demulsification rates were noted upon the addition of organic substances to the oil samples. Furthermore, an increase in the concentration of high molecular compounds in the oil composition resulted in elevated surface tension, posing challenges in separating the water phase from the oil. The demulsification ability of organic substances added to crude oil samples, compositions A, B and C (25% n-hexane and 75% phenol (conditional name A), 50% n-hexane and 50% phenol (conditional name B), 75% n-hexane and 25% phenol (conditional name C)) prepared on the basis of these organic substances was examined depending on the surface tension.

Self-carbon-thermal-reduction strategy for boosting the Fenton-like activity of single Fe-N4 sites by carbon-defect engineering

Carbon-defect engineering in metal single-atom catalysts by simple and robust strategy, boosting their catalytic activity, and revealing the carbon defect-catalytic activity relationship are meaningful but challenging. Herein, we report a facile self-carbon-thermal-reduction strategy for carbon-defect engineering of single Fe-N4 sites in ZnO-Carbon nano-reactor, as efficient catalyst in Fenton-like reaction for degradation of phenol. The carbon vacancies are easily constructed adjacent to single Fe-N4 sites during synthesis, facilitating the formation of C-O bonding and lowering the energy barrier of rate-determining-step during degradation of phenol. Consequently, the catalyst Fe-NCv-900 with carbon vacancies exhibits a much improved activity than the Fe-NC-900 without abundant carbon vacancies, with 13.5 times improvement in the first-order rate constant of phenol degradation. The Fe-NCv-900 shows high activity (97% removal ratio of phenol in only 5 min), good recyclability and the wide-ranging pH universality (pH range 3-9). This work not only provides a rational strategy for improving the Fenton-like activity of metal single-atom catalysts, but also deepens the fundamental understanding on how periphery carbon environment affects the property and performance of metal-N4 sites.

Insight into the interaction mechanism between mulberry polyphenols and β-lactoglobulin

The interaction mechanism of components in complex food systems is one of the hot topics in food science. Both protein and polyphenols co-exists in many foods, but their interaction mechanism is very difficult to elucidate. In this paper, the interaction between mulberry polyphenols (MP) and β-lactoglobulin (β-LG) was investigated based on individual phenolic ratios in MP to explore impact of MP on β-LG. The results showed that the effects of MP on β-LG could be reproduced by simulated MP (sMP) which was composed of the main individual phenolics in MP. MP, sMP and individual phenolics interacted with β-LG through static quenching, in which MP, sMP, cyanindin-3-rutinoside (C3R) and epicatechin (EC) bound to β-LG via hydrogen bonds and van der Waals force; cyanindin-3-glucose (C3G) and p-coumaric acid (PCA) bound to β-LG via hydrogen bonds and hydrophobic interactions; but quercetin (Q), rutin (R), protocatechuic acid (PA) and pelargonidin-3-glucosid (Pg3G) bound to β-LG mainly through hydrophobic interaction. Addition of MP, sMP or most individual phenolics of MP significantly increased the particle size of β-LG. C3G, C3R, PCA, Q and R, with varying degrees of influence, markedly changed secondary structure of β-LG by affecting the microenvironment of amino acids residues. Furthermore, R, PCA, EC and Pg3G induced the transition from β-fold to α-helix of β-LG, making the protein more stable. The contribution of each individual phenolic to the interaction between MP and β-LG was mainly dose-dependent and also influenced by their chemical structures.

Reactivity Enhancement of Lignin Extracted from Preconditioning Refiner Chemical-Recycle Bleached Mechanized Pulp (PRC-RBMP) Black Liquor by Phenolation

Despite black liquor’s (BL) renown as a difficult-to-manage contaminant in the pulp and paper industry, BL has been found as a viable alternative material for adhesive formulation due to its high lignin content. Nevertheless, modification is required to enhance lignin’s reactivity, and there is currently a lack of study focusing on this aspect for BL-lignin. This study aims to increase the phenolic hydroxyl content of BL-lignin by phenolation. After being phenolated at lignin to phenol ratio of 1:1, at a temperature of 100°C for 110 minutes, and with the addition of 8% sulfuric acid (H2SO4) as a catalyst, the phenolic hydroxyl content improved by 51.5%. The results of Fourier transform infrared spectroscopy (FTIR), UV/Vis spectrophotometry, proton nuclear magnetic resonance (1H-NMR), thermogravimetry-differential scanning calorimetry (TG-DSC), and its differential curve showed that the structural change in phenolated lignin opened up more active sites, implying that this lignin could be a good substitute for phenol in phenol-formaldehyde resin manufacturing.

Investigation of the extraction ability and mechanism of environmentally friendly ionic liquids for phenol in the model oil

The large number of phenolic compounds contained in coal tar and coal-converted oil seriously increased their cost of processing and transportation difficulties, so methods for efficient separation of phenolic compounds is of great industrial significance. Based on the flexible designability of ionic liquids, hydroxyl functional group that can interact with phenol were introduced into ionic liquid’s cations, eight ionic liquids were synthesized and their separation properties of phenol in model oil (methylbenzene) were studied. Cations of these ionic liquids have a significant influence the phenol extraction efficiency, which follows the order: [Ch]+ > [HEMIM]+. But the anions show a relatively small influence, and the order is: [Pro]- > [Lac]- > [Gly]- > [Ac]-. Other effects such as extraction temperature, molar ratio of phenol to ILs, extraction time and other factors on the extraction efficiency and distribution coefficient were investigated, also the optimum parameters were obtained. Hydroxyl modified ionic liquids showed good extraction performance for phenol, and the choline propionate ionic liquids showed the best separating capacity and were selected as the best extractant. The extraction performance was analyzed by 1H NMR and FT-IR spectra analysis. Hydrogen bond was confirmed to be one of the extraction mechanisms and we found that there was an optimal distance between the cation and anion of ionic liquids to form hydrogen bonds with phenol, also the π-π interaction between imidazole ring and benzene ring in phenol contributed to the extraction. In addition, the ionic liquid showed good recyclability and the regenerated ionic liquids could be reused five times with highly extraction efficiency.

A super-hydrophilic honeycomb activated carbon evaporator for simultaneous salt rejection and VOCs removal during solar-driven seawater desalination

Salt accumulation and volatile organic compounds (VOCs) entering condensed freshwater are two main drawbacks in the new approach of solar-driven seawater desalination. In this work, a super-hydrophilic honeycomb activated carbon (SHHAC) evaporator was fabricated for simultaneous salt rejection and VOCs removal. The optimal water evaporation rate of the SHHAC evaporator was as high as 1.50 kg·m−2·h−1 under one sun illumination with the corresponding photothermal conversion efficiency of 99.4 %. Due to the super-hydrophilic properties, high water absorption capacity, fast water absorption rate and unique honeycomb structure of SHHAC, the salt-rejection property of the SHHAC evaporator was achieved by flowing back the concentrated brine to the underneath seawater. Simultaneously, the distillation concentration ratio (RD) of phenol was reduced from 75 % to 0 % by the SHHAC evaporator resulting in zero phenol entering condensed freshwater. Finally, the potential application of the SHHAC evaporator was demonstrated by an expanded outdoor experiment using the real seawater as the feedwater.

Dual-chamber microbial fuel cells as biosensors for the toxicity detection of benzene, phenol, chromium, and copper in wastewater: Applicability investigation, effect of various catholyte solutions, and life cycle assessment

Microbial fuel cells (MFCs) were investigated as biosensors for the toxicity detection of benzene, phenol, chromium, and copper in wastewater as they can instantaneously indicate the presence of these contaminants. In this study, two rectangular MFCs, each composed of anodic and cathodic chambers separated by a proton exchange membrane, were operated in parallel. The anode comprised plain carbon cloth, and the cathode comprised plain carbon cloth covered by 0.5 mg/cm2 20% Pt. The anode chamber was filled with synthetic wastewater containing the designated chemical oxygen demand (COD) concentration, while the cathode chamber was filled with ferricyanide (MFC-F) or aerated tap water (MFC-T). The external resistances varied from 100 − 10,000 Ω, and organic load was assessed at COD values of 500, 750, and 1000 mg/L at a pH of 7. Toxic injections were performed at concentrations of 1, 5, 20, and 100 mg/L. Scanning electron microscope images revealed the formation of biofilm after the start-up period. The results indicate that the contaminants investigated caused an inhibitory effect when present at high concentrations. The inhibition ratios of benzene, phenol, chromium, and copper reached 2.9%, 5.1%, 41.8%, and 13.3%, respectively, for MFC-F. For MFC-T, the inhibition ratios of benzene, phenol, chromium, and copper were 14.3%, 10%, 10%, and 4.7%, respectively. MFC-T was more sensitive to the toxicity of organic compounds, while MFC-F was found to be more sensitive to heavy metal toxicity. A life cycle assessment was also conducted to determine the environmental impacts associated with the two biosensors.

Оптимизация процесса каталитического циклоалкилирования фенола 1-метилциклопентеном

The work presents the results of a study of the cycloalkylation reaction of phenol with 1-methylcyclopentene and the calculation of a regression mathematical model of the process. KN-30 was used as a process catalyst. The effect of input factors (temperature, time, molar ratios of starting components and amount of catalyst) on the yield and selectivity of para-(1-methylcyclopentyl) phenol was studied. As a result, the optimal conditions for obtaining para-(1-methylcyclopentyl) phenol with high yield and selectivity were found. When studying the reaction of cycloalkylation of phenol with 1-methylcyclopentene in the presence of a KH-30 catalyst, it was found that a high yield of the target product of 71.2% (for taken phenol), a selectivity of -92.8% (for the target product) was obtained under the following conditions: temperature - 110 ° C, duration reactions - 5 hours, the molar ratio of phenol to 1-methylcyclopentene 1:1, the amount of catalyst 10% based on the taken phenol. The chemical structure of the synthesized para-(1-methylcyclopentyl) phenol was confirmed by IR, 1Н and 13С NMR methods and its physicochemical parameters were determined. A regression mathematical model of the cycloalkylation process was calculated and the parameters of the optimal mode were found. With the calculated optimal values of the input variables found, a control experiment was set up, which made it possible to find the yield values of the target product Y1=78%, which indicates the acceptability of the developed regression model.

Синтез 2-гидрокси-5(3-метилциклогексил) ацето- и бензофенонов в присутствии нано-каталитической системы

The results of studying of the cycloalkylation reaction of phenol with 3-methylcyclohexene in the presence of zeolite Y impregnated with phosphoric acid are presented. It was found that in order to achieve a high yield (71.2%) and selectivity (93.7%) during the cycloalkylation reaction of phenol with 3-methylcyclohexene, the reaction conditions should be as follows: reaction temperature 120 oC, molar ratio of phenol to 3-methylcyclohexene 1:1, volume velocity 0.5 h-1. The results of the synthesis of 2-hydroxy-5(3-methylcyclohexyl) aceto- and benzophenones by the reaction of p-(3-methylcyclohexyl) phenol with acetic acid (AcOH) and benzoyl chloride (BzCl) with the participation of nanosized ZnCl2 as a catalyst are presented. It was found that at a temperature of 140 oC, a reaction time of 40 minutes, and a molar ratio of p-(3-methylcyclohexyl) phenol to AcOH (BzCl) of 1:2, the yield of the target products was 63.3-66.7%.

A recyclable UCST-type biocatalyst to catalyze H2O2 degradation of phenol

Horseradish peroxidase (HRP) is a kind of enzyme commonly used in clinical trials that is rich in the plant horseradish. It has a wide range of applications in the fields of pharmacy and pollution control. However, free enzymes are easily denatured and inactivated by environmental influences, which is not conducive to the normal progress of the reaction. At the same time, the cost of enzymes is relatively high, and it is difficult to separate and recover during the reaction. In this study, the UCST-type temperature- responsive polymer was combined with HRP under the optimal immobilization reaction conditions of 3% polymer solution concentration, 60 ℃, and pH= 8 through affinity interaction to produce UCST-type smart polymerase. The smart polymerase has stronger temperature stability, pH stability and storage stability than free enzymes. In the simulated pollutant degradation experiment, under the molar ratio of phenol to H2O2 is 1:1, the temperature of 60 ℃, and pH= 7, smart polymerase can degrade 91% of phenol in a 100 mg/L phenol solution within 1 h. After five cycles of catalytic reaction, 68% of smart polymerase was recovered through cooling precipitation. In the phenol degradation experiments of two different real water samples, 88% and 90% of the phenol in the water were removed, respectively, and most of the highly active immobilized enzymes were recovered at the same time. Finally, the biotoxicity of the catalyzed reaction product is significantly reduced was demonstrated.

Molecular‐Multiproxy Assessment of Land‐Derived Organic Matter Degradation Over Extensive Scales of the East Siberian Arctic Shelf Seas

AbstractGlobal warming triggers permafrost thaw, which increases the release of terrigenous organic matter (terr‐OM) to the Arctic Ocean by coastal erosion and rivers. Terrigenous OM degradation in the Arctic Ocean contributes to greenhouse gas emissions and severe ocean acidification, yet the vulnerability of different terr‐OM components is poorly resolved. Here, terr‐OM degradation dynamics are studied with unprecedented spatial coverage over the World's largest shelf sea system—the East Siberian Arctic Shelf (ESAS), using a multi‐proxy molecular biomarker approach. Mineral‐surface‐area‐normalized concentrations of terr‐OM compounds in surface sediments decreases offshore. Differences between terr‐OM compound classes (lignin phenols, high‐molecular weight [HMW] n‐alkanes, n‐alkanoic acids and n‐alkanols, sterols, 3,5‐dihydroxybenzoic acids, cutin acids) reflect contrasting influence of sources, propensity to microbial degradation and association with sedimenting particles, with lignin phenols disappearing 3‐times faster than total terr‐OM, and twice faster than other biomarkers. Molecular degradation proxies support substantial terr‐OM degradation across the ESAS, with clearest trends shown by: 3,5‐dihydroxybenzoic acid/vanillyl phenol ratios, acid‐to‐aldehyde ratios of syringyl and vanillyl phenols, Carbon Preference Indices of HMW n‐alkyl compounds and sitostanol/β‐sitosterol. The combination of terr‐OM biomarker data with δ13C/Δ14C‐based source apportionment indicates that the more degraded state of lignin is influenced by the relative contribution of river‐transported terr‐OM from surface soils, while HMW n‐alkanoic acids and stigmasterol are influenced by erosion‐derived terr‐OM from Ice Complex deposits. Our findings demonstrate differences in vulnerability to degradation between contrasting terr‐OM pools, and underscore the need to consider molecular properties for understanding and modeling of large‐scale biogeochemical processes of the permafrost carbon‐climate feedback.

Synthesis and characterization of poly(benzoxazine‐co‐siloxane) oligomers end‐capped with arylacetylene

AbstractFour poly(benzoxazine‐co‐siloxane) oligomers (PBcSs) were successfully synthesized by improving the synthesis step and controlling the ratio of phenol, bisphenol A, 1,3‐bis(3‐aminopropyl)tetramethyldisiloxane, m‐aminophenyl acetylene, and formaldehyde; the resulting compounds all exhibited good processing properties. Siloxane addition can significantly improve the toughness of the polybenzoxazines. Additionally, compared with the PBcSs containing only phenol structure, the introduction of bisphenol A has a decelerating effect on the polymerization process of the benzoxazine oligomer, which leads to an increase in the exothermic peak temperature. Simultaneously, the PBcS containing bisphenol A also exhibits a higher glass transition temperature and increased thermal stability, but reduced flexural strength. Conversely, compared to the benzoxazine oligomers that do not contain alkynyl groups, the introduction of the terminal alkynyl group can accelerate the polymerization process, decrease the exothermic peak temperature, significantly increase the glass transition temperature, and greatly improve the heat resistance; the 5% thermal decomposition temperature of cured product is increased by up to 101°C. Furthermore, under conditions that ensure high flexural strength, appropriate alkynyl content can also significantly increase the material's flexural modulus.

Phenol Liquefaction of Waste Sawdust Pretreated by Sodium Hydroxide: Optimization of Parameters Using Response Surface Methodology.

In this study, a two-step method was used to realize the liquefaction of waste sawdust under atmospheric pressure, and to achieve a high liquefaction rate. Specifically, waste sawdust was pretreated with NaOH, followed by liquefaction using phenol. The relative optimum condition for alkali-heat pretreatment was a 1:1 mass ratio of NaOH to sawdust at 140 °C. The reaction parameters including the mass ratio of phenol to pretreated sawdust, liquefaction temperature, and liquefaction time were optimized by response surface methodology. The optimal conditions for phenol liquefaction of pretreated sawdust were a 4.21 mass ratio of phenol to sawdust, a liquefaction temperature of 173.58 °C, and a liquefaction time of 2.24 h, resulting in corresponding liquefied residues of 6.35%. The liquefaction rate reached 93.65%. Finally, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) were used to analyze untreated waste sawdust, pretreated sawdust, liquefied residues, and liquefied liquid. SEM results showed that the alkali-heat pretreatment and liquefaction reactions destroyed the intact, dense, and homogeneous sample structures. FT-IR results showed that liquefied residues contain aromatic compounds with different substituents, including mainly lignin and its derivatives, while the liquefied liquid contains a large number of aromatic phenolic compounds. XRD showed that alkali-heat pretreatment and phenol liquefaction destroyed most of the crystalline regions, greatly reduced the crystallinity and changed the crystal type of cellulose in the sawdust.

Bifunctional Pt/Hβ catalyzed alkylation and hydrodeoxygenation of phenol and cyclohexanol in one-pot to synthesize high-density fuels

Synthesis of fuels from lignin bio-oil feedstock significantly alleviates energy crises and environmental pollution. Phenol is the simplest model compound for lignin bio-oil feedstocks, and the synthesis of fuel precursors from phenol through alkylation has received increasing attention. Here we report a one-pot strategy for preparing polycyclic alkane high-density fuels from phenol and cyclohexanol over bifunctional Pt/Hβ catalyst by combining alkylation with following hydrodeoxygenation (HDO). The activity of different zeolites for catalyzing the alkylation of phenol and cyclohexanol was explored. It was found that the larger pore size of alkali treated Hβ would not limit the production of polycyclic compounds, and good acid content in a particular mesoporous specific surface area can speed up the reaction rate. The one-pot reaction conditions were then optimized. When the alkali treatment concentration is 0.2 mol/L, the metal loading is 0.2 wt%, and the molar ratio of phenol and cyclohexanol is 1:1, the highest conversion of phenol can reach more than 83 %. The selectivity of alkylphenol can reach more than 97 %, and the yield of bicyclic and tricyclic rings in the final product after HDO can reach 83.42 %. The bifunctional catalyst can also realize the coupling of other acid-catalyzed carbon growth reactions and metal-catalyzed HDO reactions, which allows the direct synthesis of fuel from lignin oil or other biomass compounds.

Diagnostic ratio of nitrated phenols as a new method for the identification of pollution emission sources

Nitrated phenols (NPs) are emitted from biomass burning and vehicles emissions, or produced by oxidation of phenolic precursors. Previous studies have investigated the emission factors of NPs from various primary emission sources. However, there is no study on the source apportionment method for the diagnostic ratio of NPs. In this study, a new source apportionment method is established using a diagnostic ratio of NPs. Two categories (methyl-nitrocatechols and methyl-nitrophenols) of NP diagnostic ratios, are proposed for source apportionment of primary aerosols. In order to show the accuracy of this source apportionment method, it was applied to the source apportionment of atmospheric NPs in both urban (Kathmandu, Nepal) and remote areas (Lulang, Tibetan Plateau, China). The results show that biomass burning is a common emission source for atmospheric NPs in Kathmandu and Lulang, with vehicle emissions being another important emission source. The atmospheric NPs in the urban area of Kathmandu are commonly from gasoline motorbike emissions, while the atmospheric NPs in Lulang derive from diesel vehicles, throughout the year. The conclusions of the source apportionment study were consistent with the actual vehicle types of local residents in Kathmandu and Lulang, which further proves the reliability of the NP diagnostic ratios method.

Inhibition of Phenol from Entering into Condensed Freshwater by Activated Persulfate during Solar-Driven Seawater Desalination.

Recently, solar-driven seawater desalination has received extensive attention since it can obtain considerable freshwater by accelerating water evaporation at the air-water interface through solar evaporators. However, the high air-water interface temperature can cause volatile organic compounds (VOCs) to enter condensed freshwater and result in water quality safety risk. In this work, an antioxidative solar evaporator, which was composed of MoS2 as the photothermal material, expandable polyethylene (EPE) foam as the insulation material, polytetrafluoroethylene (PTFE) plate as the corrosion resistant material, and fiberglass membrane (FB) as the seawater delivery material, was fabricated for the first time. The activated persulfate (PS) methods, including peroxymonosulfate (PMS) and peroxodisulfate (PDS), were applied to inhibit phenol from entering condensed freshwater during desalination. The distillation concentration ratio of phenol (RD) was reduced from 76.5% to 0% with the addition of sufficient PMS or PDS, which means that there was no phenol in condensed freshwater. It was found that the Cl- is the main factor in activating PMS, while for PDS, light, and heat are the dominant. Compared with PDS, PMS can make full utilization of the light, heat, Cl- at the evaporator's surface, resulting in more effective inhibition of the phenol from entering condensed freshwater. Finally, though phenol was efficiently removed by the addition of PMS or PDS, the problem of the formation of the halogenated distillation by-products in condensed freshwater should be given more attention in the future.