The alkylation of p-cresol with tert-butanol(TBA)to 2-tert-butyl-p-cresol(TBC)catalyzed by a novel multiple-SO3H functioned ionic liquid(IL1)was investigated.Meanwhile,the catalytic activity of this novel ionic ...The alkylation of p-cresol with tert-butanol(TBA)to 2-tert-butyl-p-cresol(TBC)catalyzed by a novel multiple-SO3H functioned ionic liquid(IL1)was investigated.Meanwhile,the catalytic activity of this novel ionic liquid was compared with other four traditional ionic liquids.The results showed that IL1 has superior catalytic activity to other four traditional ionic liquids with the conversion of 85.3%and selectivity of 95.2%.Also,the reaction conditions were investigated to obtain the optimum conditions.Operational simplicity,small amount of usage,high activity,reusability and selectivity are the key features of this methodology.展开更多
Laboratory-scale experiments were carried out to evaluate the influences of operational parameters on the melt crystallization efficiency for p-cresol purification.The optimal crystallization conditions were determine...Laboratory-scale experiments were carried out to evaluate the influences of operational parameters on the melt crystallization efficiency for p-cresol purification.The optimal crystallization conditions were determined:dynamic pulsed aeration at 90 L·h-1 and the cooling rate of 0.6-0.8 ℃·min-1,followed by sweating at 0.2-0.3 ℃·min-1 for 40 min.Results also demonstrate that the melt crystallization efficiency is sensitive to feed concentration,which highlights this technology for separation and purification of high purity products.展开更多
Biological removal of sulfide, nitrate, and p-cresol at a loading rate of 340 gS/(m^3 · d), 340 gN/(m^3 · d) and600 gC/(m^3 · d), respectively, was achieved in an upflow anaerobic sludge blanket(UASB) r...Biological removal of sulfide, nitrate, and p-cresol at a loading rate of 340 gS/(m^3 · d), 340 gN/(m^3 · d) and600 gC/(m^3 · d), respectively, was achieved in an upflow anaerobic sludge blanket(UASB) reactor. The ratio of C/S could affect the elemental sulfur(S^0) accumulation, and the C/S ratio of 1.75:1 was optimal for S^0 accumulation. Strains Pseudomonas sp., Simplicispira sp., and Rhizobium sp. could likely yield heterotrophs. Strains Arcobacter sp.,Sulfurimonas sp., Sulfurovum sp., and Sulfurospirillum sp. are the autotrophics required for the proposed UASB system. At high loading rate, the autotrophic denitrification pathway declined faster than the heterotrophic pathway.展开更多
In this study,extraction of p-cresol from the simulated wastewater has been studied using centrifugal extractors and QH-1 extractant.The distribution ratio of p-cresol was approximately 308.5 in the QH-1-p-cresol(pH=2...In this study,extraction of p-cresol from the simulated wastewater has been studied using centrifugal extractors and QH-1 extractant.The distribution ratio of p-cresol was approximately 308.5 in the QH-1-p-cresol(pH=2.0)system.The extraction stage efficiency of the single-stage centrifugal extractor was higher than 92%,and the extraction rate of the three-stage cascade was higher than 99%.When 15% NaOH was used for the stripping of p-cresol in QH-1 solution,the stripping rate of the three-stage cascade reached 100%.A mathematical model of multistage countercurrent extraction process that considers the phase volume change,extraction stage efficiency,and phase entrainment was used to simulate the extraction of p-cresol using centrifugal extractors.The calculated results using this model were in good agreement with the experimental results.展开更多
A silica-supported cross-linked poly(maleic acid -co- styrene)-platinum complex (PMS-Pt) has been prepared and found to be active in the hydrogenation of p-cresol under mild conditions (303-323K, 1.01 x 10(5)Pa). In t...A silica-supported cross-linked poly(maleic acid -co- styrene)-platinum complex (PMS-Pt) has been prepared and found to be active in the hydrogenation of p-cresol under mild conditions (303-323K, 1.01 x 10(5)Pa). In this hydrogenation system water serves as a solvent and p-cresol can be converted to 4-methylcyclohexanol quantitatively via 4-methylcyclohexanone as intermediate.展开更多
The cultivation of aerobic granules in sequencing batch reactor for the biodegradation of p-cresol was studied. The reactor was started with 100 mg/L of p-cresol. Aerobic granules first appeared within one month of st...The cultivation of aerobic granules in sequencing batch reactor for the biodegradation of p-cresol was studied. The reactor was started with 100 mg/L of p-cresol. Aerobic granules first appeared within one month of start up. The granules were large and strong and had a compact structure. The diameter of stable granules was in the range of 1-5 mm. The integrity coefficient and granules density was found to be 96% and 1046 kg/m3, raspectively, The settling velocity of granules was found to be in the range of 2×10^-2-6×10^-7 m/sec. The aerobic granules were able to degrade p-cresol upto 800 mg/L at a removal efficiency of 88%. Specific p-cresol degradation rate in aerobic granules followed Haldane model for substrate inhibition, High specific p-cresol degradation rate up to 0,96 g pcresol/(g VSS.day) were sustained upto p-cresol concentration of 400 mg/L, Higher removal efficiency, good settling characteristics of aerobic granules, makes sequencing batch reactor suitable for erLhaneing the microorganism potential for biodegradation of inhibitory compounds.展开更多
The influence of the wettability of a catalyst on the performance of the liquid phase oxidation of p-cresol was investigated. It was found that the surface hydrophobicity of a catalyst, which can be changed by modific...The influence of the wettability of a catalyst on the performance of the liquid phase oxidation of p-cresol was investigated. It was found that the surface hydrophobicity of a catalyst, which can be changed by modification with various loadings of polyvinylidene fluoride(PVDF), has a promotion effect on the catalytic performance. At the same time, the reaction parameters such as oxygen pressure, molar ratio of NaOH to p-cresol, reaction temperature and time on the catalytic performance in the liquid-phase oxidation of p-cresol were optimized. As a result, 10%(mass fraction) PVDF modified cobalt pyrophosphate gave the highest conversion of 94.2% of p-cresol with a selectivity of 94.4% for p-hydroxybenzaldehyde at 348 K and a molar ratio of4:l of NaOH/p-cresol and an oxygen pressure of 1.0 MPa for 3 h.展开更多
基金Supported by the National High Technology Research and Development Program of China(2006BAE03B06)Shanghai Leading Academic Discipline Project(B409)Shanghai International Cooperation of Science and Technology Project(06SR07101)
文摘The alkylation of p-cresol with tert-butanol(TBA)to 2-tert-butyl-p-cresol(TBC)catalyzed by a novel multiple-SO3H functioned ionic liquid(IL1)was investigated.Meanwhile,the catalytic activity of this novel ionic liquid was compared with other four traditional ionic liquids.The results showed that IL1 has superior catalytic activity to other four traditional ionic liquids with the conversion of 85.3%and selectivity of 95.2%.Also,the reaction conditions were investigated to obtain the optimum conditions.Operational simplicity,small amount of usage,high activity,reusability and selectivity are the key features of this methodology.
基金Supported by the National Basic Research Program of China (2009CB219905)Program for Changjiang Scholars and Innovative Research Team in University (IRT0936)Innovating Fund of Tianjin University
文摘Laboratory-scale experiments were carried out to evaluate the influences of operational parameters on the melt crystallization efficiency for p-cresol purification.The optimal crystallization conditions were determined:dynamic pulsed aeration at 90 L·h-1 and the cooling rate of 0.6-0.8 ℃·min-1,followed by sweating at 0.2-0.3 ℃·min-1 for 40 min.Results also demonstrate that the melt crystallization efficiency is sensitive to feed concentration,which highlights this technology for separation and purification of high purity products.
基金supported by the National Natural Science Foundation of China under Grant No. 21307160the Fundamental Research Funds for the Central Universities under Grant No. 16CX02040A
文摘Biological removal of sulfide, nitrate, and p-cresol at a loading rate of 340 gS/(m^3 · d), 340 gN/(m^3 · d) and600 gC/(m^3 · d), respectively, was achieved in an upflow anaerobic sludge blanket(UASB) reactor. The ratio of C/S could affect the elemental sulfur(S^0) accumulation, and the C/S ratio of 1.75:1 was optimal for S^0 accumulation. Strains Pseudomonas sp., Simplicispira sp., and Rhizobium sp. could likely yield heterotrophs. Strains Arcobacter sp.,Sulfurimonas sp., Sulfurovum sp., and Sulfurospirillum sp. are the autotrophics required for the proposed UASB system. At high loading rate, the autotrophic denitrification pathway declined faster than the heterotrophic pathway.
文摘In this study,extraction of p-cresol from the simulated wastewater has been studied using centrifugal extractors and QH-1 extractant.The distribution ratio of p-cresol was approximately 308.5 in the QH-1-p-cresol(pH=2.0)system.The extraction stage efficiency of the single-stage centrifugal extractor was higher than 92%,and the extraction rate of the three-stage cascade was higher than 99%.When 15% NaOH was used for the stripping of p-cresol in QH-1 solution,the stripping rate of the three-stage cascade reached 100%.A mathematical model of multistage countercurrent extraction process that considers the phase volume change,extraction stage efficiency,and phase entrainment was used to simulate the extraction of p-cresol using centrifugal extractors.The calculated results using this model were in good agreement with the experimental results.
文摘A silica-supported cross-linked poly(maleic acid -co- styrene)-platinum complex (PMS-Pt) has been prepared and found to be active in the hydrogenation of p-cresol under mild conditions (303-323K, 1.01 x 10(5)Pa). In this hydrogenation system water serves as a solvent and p-cresol can be converted to 4-methylcyclohexanol quantitatively via 4-methylcyclohexanone as intermediate.
基金supported by UP Council of Science and Technology (UPCST), Uttar Pradesh, India
文摘The cultivation of aerobic granules in sequencing batch reactor for the biodegradation of p-cresol was studied. The reactor was started with 100 mg/L of p-cresol. Aerobic granules first appeared within one month of start up. The granules were large and strong and had a compact structure. The diameter of stable granules was in the range of 1-5 mm. The integrity coefficient and granules density was found to be 96% and 1046 kg/m3, raspectively, The settling velocity of granules was found to be in the range of 2×10^-2-6×10^-7 m/sec. The aerobic granules were able to degrade p-cresol upto 800 mg/L at a removal efficiency of 88%. Specific p-cresol degradation rate in aerobic granules followed Haldane model for substrate inhibition, High specific p-cresol degradation rate up to 0,96 g pcresol/(g VSS.day) were sustained upto p-cresol concentration of 400 mg/L, Higher removal efficiency, good settling characteristics of aerobic granules, makes sequencing batch reactor suitable for erLhaneing the microorganism potential for biodegradation of inhibitory compounds.
基金Supported by the National Natural Science Foundation of China(No.21177120) and the National High Technology Research and Development Program of China(No.2011AA03A406).
文摘The influence of the wettability of a catalyst on the performance of the liquid phase oxidation of p-cresol was investigated. It was found that the surface hydrophobicity of a catalyst, which can be changed by modification with various loadings of polyvinylidene fluoride(PVDF), has a promotion effect on the catalytic performance. At the same time, the reaction parameters such as oxygen pressure, molar ratio of NaOH to p-cresol, reaction temperature and time on the catalytic performance in the liquid-phase oxidation of p-cresol were optimized. As a result, 10%(mass fraction) PVDF modified cobalt pyrophosphate gave the highest conversion of 94.2% of p-cresol with a selectivity of 94.4% for p-hydroxybenzaldehyde at 348 K and a molar ratio of4:l of NaOH/p-cresol and an oxygen pressure of 1.0 MPa for 3 h.