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Chinese Journal of Chemical Engineering 2022年第4期35卷 377-383页

作者： Hanghang Li Wei Zhao Licheng Wu Qian Wang Danhong Shang Qin Zhong School of Energy&Power Engineering Jiangsu UniversityZhenjiang 212013China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

A series of B-doped V_(2)O_(5)/TiO_(2) catalysts has been prepared the by sol-gel and impregnation methods to investigate the influence of B-doping on the selective catalytic reduction(SCR)of NOxwith NH_(3).X-ray diffraction,Brunauer-Emmett-Teller specific surface area,scanning electron microscope,X-ray photoelectron spectroscopy,temperature-programmed reduction of H_(2) and temperature-programmed desorption of NH_(3)technology were used to study the effect of the B-doping on the structure and NH_(3)-SCR activity of V_(2)O_(5)/TiO_(2) *** experimental results demonstrated that the introduction of B not only improved the low-temperature SCR activity of the catalysts,but also broadened the activity temperature *** best SCR activity in the entire test temperature range is obtained for VTiB_(2.0) with 2.0%doping amount of B and the NO_(x) conversion rate is up to 94.3%at 210℃.The crystal phase,specific surface area,valence state reducibility and surface acidity of the active components for the as-prepared catalysts are significantly affected by the B-doping,resulting in an improved NH_(3)-SCR *** results suggest that the V_(2)O_(5)/TiO_(2) catalysts with an appropriate B content afford good candidates for SCR in the low temperature window.

关键词： B-doping catalyst SCR NO_(x) Support

Non-phosgene synthesis of hexamethylene-1,6-diisocyanate from thermal decomposition of hexamethylene-1,6-dicarbamate over Zn–Co bimetallic supported ZSM-5 catalyst

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Chinese Journal of Chemical Engineering 2019年第3期27卷 549-555页

作者： Yan Cao Yafang Chi Ammar Muhammad Peng He liguo Wang Huiquan Li CAS Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

A non-phosgene route for the synthesis of hexamethylene-1,6-diisocyanate(HDI) was developed via catalytic decomposition of hexamethylene-1,6-dicarbamate(HDC) over Zn–Co bi-metallic supported ZSM-5 *** catalyst was characterized by FTIR and XRD analyses. Three solvents dioctyl sebacate(DOS), dibutyl sebacate(DBS) and 1-butyl-3-methylimidazolium tetrafluoroborate(BMIMBF_4) were investigated and compared; DOS gave better performance. The catalytic performances for thermal decomposition of HDC to HDI using DOS as solvent were then investigated, and the results showed that, under the optimized reaction conditions, i.e.,10 wt%concentration of HDC in DOS, 250 °C temperature, 60 min reaction time, 83.8% yield of HDI had been achieved over Zn–Co/ZSM-5. Decomposition of the intermediate hexamethylene-1-carbamate-6-isocyanate(HMI) over Zn–Co/ZSM-5 in DOS solvent was further studied and the results indicated that yield of HDI from HMI reached to 69.6%(98.6% HDI selectively) at 270 °C, which further increased the yield of the total HDI(HDI_(tol)) to as high as 95.0%. Recycling of catalyst showed that HDI and HMI yield slightly decreased, and by-product yield increased after the catalyst was reused for 4 times. At last possible reaction mechanism was proposed.

关键词： Non-phosgene Thermal decomposition Hexamethylene-1,6-diisocyanate Hexamethylene-1,6-dicarbamate Bimetallic supported ZSM-5 catalyst

Local structural evolutions of CuO/ZnO/Al2O3 catalyst for methanol synthesis under operando conditions studied by in situ quick X-ray absorption spectroscopy

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Nuclear Science and Techniques 2017年第2期28卷 35-43页

作者： Xue-Ping Sun Fan-Fei Sun Song-Qi Gu Jing Chen Xian-Long Du Jian-Qiang Wang Yu-Ying Huang Zheng Jiang Shanghai Institute of Applied Physics Chinese Academy of Sciences Zhangjiang Campus Shanghai 201204 China University of Chinese Academy of Sciences Beijing 100049China

In situ quick X-ray absorption spectroscopy(QXAFS) at the Cu and Zn K-edge under operando conditions has been used to unravel the Cu/Zn interaction and identify possible active site of CuO/ZnO/Al_2O_3 catalyst for methanol synthesis. In this work, the catalyst, whose activity increases with the reaction temperature and pressure, was studied at calcined, reduced, and reacted conditions. TEM and EDX images for the calcined and reduced catalysts showed that copper was distributed uniformly at both conditions. TPR profile revealed two reduction peaks at 165 and 195 °C for copper species in the calcined catalyst. QXAFS results demonstrated that the calcined form consisted mainly of a mixed Cu O and Zn O, and it was progressively transformed into Cu metal particles and dispersed Zn O species as the reduction treatment. It was demonstrated that activation of the catalyst precursor occurred via a Cu^+intermediate, and the active catalyst predominantly consisted of metallic Cu and Zn O evenunder higher pressures. Structure of the active catalyst did not change with the temperature or pressure, indicating that the role of the Zn was mainly to improve Cu *** indicates the potential of QXAFS method in studying the structure evolutions of catalysts in methanol synthesis.

关键词： In situ Quick X-ray absorption spectroscopy CuO/ZnO/Al2O3 catalyst Operando condition

DEVELOPMENT OF A catalyst FOR SOLUTION OF POLY(VINYL ALCOHOL) IN NON-AQUEOUS MEDIUM

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Chinese Journal of Polymer Science 2008年第4期26卷 501-506页

作者： Prafulla Chetri Narendra Nath Dass Neelotpal Sen Sarma Material Science Division IASSTPaschim BoragaonGuwahati-781035AssamIndia

Chloro ethane dimethyl sulfoxide,C_2H_5Cl·DMSO(ECI·DMSO)was prepared by interaction of acrylic acid with *** acid in dimethyl sulfoxide(DMSO)and subsequent decarboxylation with H_2O_2 *** formation of the compound was confirmed by spectral and analytical methods;the molecular weight was determined by cryoscopic *** solubility of poly(vinyl alcohol)(PVA)in different solvents or mixed solvents at 40℃,50℃and 60℃temperature in the presence of 0.01% of EC1·-DMSO was *** tu...

关键词： Chloro ethane dimethyl sulfoxide Poly(vinyl alcohol) catalyst Solubility

High nitrogen carbon material with rich defects as a highly efficient metal-free catalyst for excellent catalytic performance of acetylene hydrochlorination

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Chinese Journal of Chemical Engineering 2021年第1期34卷 196-203页

作者： Fangjie Lu Dong Xu Yusheng Lu Bin Dai Mingyuan Zhu School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832000China Key Laboratory for Green Processing of Chemical Engineering Xinjiang Production and Construction CorpsShihezi 832000China

In this work,we developed a simple strategy to synthesize a carbon material with high nitrogen and rich carbon *** approach polymerized diaminopyridine(DAP) and ammonium persulfate(APS).Following a range of different temperature pyrolysis approaches,the resulting rough surface was shown to exhibit edge defects due to N-doping on graphite carbon.A series of catalysts were evaluated using a variety of characterization techniques and tested for catalytic *** catalytic performance of the N-doped carbon material enhanced alongside an increment in carbon *** NC-800 catalyst exhibited outstanding catalytic activity and stability in acetylene hydrochlorination(C_(2) H_(2) GHSV=30 h^(-1),at 220℃,the acetylene conversion rate was 98%),with its stability reaching up to 450 *** to NC-800 having a nitrogen content of up to 13.46%,it had the largest specific surface area and a high defect amount,as well as strong C_(2) H_(2) and HCl ***-800 has excellent catalytic activity and stability to reflect its unlimited potential as a carbon material.

关键词： Carbon defects material High nitrogen content Acetylene hydrochlorination catalyst Chemical reaction Nanomaterials

Effect of cerium addition on catalytic performance of PtSnNa/ZSM-5 catalyst for propane dehydrogenation

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Journal of Natural Gas Chemistry 2012年第3期21卷 324-331页

作者： Mengwei Xue Yuming Zhou Yiwei Zhang Xuan Liu Yongzheng Duan Xiaoli Sheng School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189JiangsuChina School of Biochemical and Environmental Engineering Nanjing Xiaozhuang UniversityNanjing 211171JiangsuChina

The effect of cerium addition on the catalytic performance of propane dehydrogenation over PtSnNaIZSM-5 catalyst has been investigated by reaction tests and some physicochemical characterization such as XRD, BET, TEM, XPS, NH3-TPD, H2 chemisorption, TPR and TPO techniques. It has been found that with suitable amount of cerium addition, the platinum dispersion increased, while the carbon deposition tended to be eliminated easily. In these cases, the presence of cerium could not only realize the better distribution of metallic particles on the support, but also strengthen the interactions between Sn species and the support. Additionally, XPS spectra confirmed that more amounts of tin could exist in oxidized form, which was advantageous to the reaction. In our experiments, PtSnNaCe （1.1 wt%）/ZSM-5 catalyst exhibited the best catalytic performance. After running the reaction for 750 h, propane conversion was maintained higher than 30% with the corresponding selectivity to propylene of about 97%.

关键词： cerium Pt-Sn propane dehydrogenation catalyst

Mathematical analysis of physicochemical phenomena in the catalyst during hydrogenating depolymerization of coal extract benzene insoluble fraction

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Chinese Journal of Chemical Engineering 2015年第6期23卷 962-973页

作者： Jerzy Szczygie Marek Stolarski Department of Chemistry Wroclaw University of Technology

Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co–Mo/Al2O3 catalyst were assessed using a mathematical model. The analytical equations of the mathematical model were generated based on material balance incorporating the physico-chemical phenomena(reaction and diffusion) both in the autoclave and the catalyst grain. The equations offer the possibility for predicting changes of the reactants in the autoclave during the process and for determining the distribution of reactant concentrations in the grain as a function of its radius. The analytical equations of the model serve as the basis of the algorithm for assessing the influence of restrictive diffusion on the effectiveness and selectivity of the catalyst, and also for defining the optimal radii of the catalyst's pores to enable free transport of reactants in the grain interior.

关键词： Coal extract Benzene insolubles catalyst Depolymerization Kinetics

Petroleum coke conversion behavior in catalyst-assisted chemical looping combustion

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2417-2424页

作者： Xianyu Liu Huijun Ge Shiwei Ma Shangyi Yin Ping Lu Laihong Shen Hongcun Bai Wei Wang Tao Song School of Energy and Mechanical Engineering Nanjing Normal UniversityNanjing 210023China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education Southeast UniversityNanjing 210096China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China SUMEC Complete Equip.&Eng.Co. LtdNanjing210018China

Efficiently using petroleum coke as fuel and reducing carbon emission meanwhile have become attractive in oil processing *** paper is focused on the application of Chemical Looping Combustion(CLC)with petroleum coke,with the purpose of investigating its combustion performance and effects of *** experiments were performed in a laboratory scale fluidized bed facility with a natural manganese-based oxygen *** results indicated that the coke conversion is very sensitive to reaction *** pre sent natural manganese-based oxygen carrier decorated by K has little effect on the improvement of coke ***,SEM-EDX,and H2-TPR were adopted to characterize the reacted oxygen carrier *** being decorated by K,the oxygen carrier's capacity of transferring oxygen was decrea sed.A calcination temperature above the melting point of K2 CO3(891℃)shows better oxygen transfer reactivity in comparison to the one calcined at a lower *** natural oxygen carrier used in the work has a high content of Si,which can easily react with K to form K(FeSi2 O6).Further,irrespective of reaction temperature,the coke conversion can be significantly enhanced by decorating the coke with K,with a demonstration of remarkably shorter reaction time,faster average coke gasification rate and higher average carbon conversion rate.

关键词： Chemical looping combustion Oxygen carrier catalyst Coke

Zirconium-containing UiO-66 as an efficient and reusable catalyst for transesterification of triglyceride with methanol

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Journal of Energy Chemistry 2016年第5期25卷 874-879页

作者： Fan Zhou Ningyue Lu Binbin Fan Huigang Wang Ruifeng Li College of Chemistry and Chemical Engineering Taiyuan University of Technology Key Laboratory of Coal Science and Technology MOE Taiyuan University of Technology

Zirconium-based MOFs of the UiO family have attracted considerable attention due to their high thermal,chemical and mechanical stability. With the aim of further exploring the applications of zirconium-based UiO-66 in acid-catalyzed reactions and elucidating the effects of the defects in UiO-66 materials on their catalytic performances, in this work, a series of zirconium-containing UiO-66 samples were synthesized by varying the synthesis temperatures and BDC/Zr(terephthalic acid/ZrCl) ratios in the synthesis *** synthesized UiO-66 samples were characterized by X-ray diffraction(XRD), Nadsorption-desorption,scanning electron microscopy(SEM), thermogravimetrical analysis(TGA), temperature-programmed desorption of NH(NH-TPD). Their catalytic performances were investigated in transesterification of tributyrin and soybean oil with methanol. The results showed that UiO-66 samples with different amounts of defects could be successfully prepared by varying the synthesis temperatures and/or the BDC/Zr ratios used in the synthesis system. The catalytic activities of the UiO-66 materials greatly depended on their linker defects and enhanced with the increase of the defect amount. The UiO-66 was an efficient catalyst for transesterification of tributyrin and soybean oil with methanol under mild reaction conditions and its catalytic activity was comparable to other solid acid catalysts reported in the literatures. The UiO-66 catalyst was relatively stable and could be reused.

关键词： Metal organic frameworks Solid acid Transesterification UiO-66 catalyst

Conversion of Glucose to Valuable Platform Chemicals over Graphene Solid Acid catalyst

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Chinese Journal of Chemical Physics 2015年第2期28卷 230-234,I0002页

作者：蒋振亚闫立峰中国科学技术大学化学物理系合肥230026

Biomass-derived hexose sugars, the most abundant renewable resources in the world, have potential to be the sustainable resources for production of platform chemicals. Here, con- version of glucose is investigated by using sulfonated graphene （rGO-SOaH） as solid acid catalyst in water without any organic solvent. At first, graphene functionalized with sulfonic acid groups is prepared by using Nail and propane sultone, and then it is characterized by means of XPS, FT-IR, and TEM to confirm the existence of the sulfonic acid groups. The catalytic activity of rGO-SOaH in the conversion of glucose to valuable chemicals is studied under different reaction conditions. The maximum yield of 5-hydroxymethylfurfural （HMF） is 28.8%, and the total yield of formic acid, lactic acid and HMF is 51.94% when the reaction is conducted at the optimized reaction condition. In addition, the rGO-SOaH gives a rela- tively high total yield of the three kinds of products after five run experiments, indicating that the catalyst shows good thermal stability.

关键词： Glucose Graphene Solid acid catalyst