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Modeling and analysis of air combustion and steam regeneration in methanol to olefins processes
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作者 Jinqiang Liang Danzhu Liu +1 位作者 Shuliang Xu Mao Ye 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期94-103,共10页
Light olefins is the incredibly important materials in chemical industry.Methanol to olefins(MTO),which provides a non-oil route for light olefins production,received considerable attention in the past decades.However... Light olefins is the incredibly important materials in chemical industry.Methanol to olefins(MTO),which provides a non-oil route for light olefins production,received considerable attention in the past decades.However,the catalyst deactivation is an inevitable feature in MTO processes,and regeneration,therefore,is one of the key steps in industrial MTO processes.Traditionally the MTO catalyst is regenerated by removing the deposited coke via air combustion,which unavoidably transforms coke into carbon dioxide and reduces the carbon utilization efficiency.Recent study shows that the coke species over MTO catalyst can be regenerated via steam,which can promote the light olefins yield as the deactivated coke species can be essentially transferred to industrially useful synthesis gas,is a promising pathway for further MTO processes development.In this work,we modelled and analyzed these two MTO regeneration methods in terms of carbon utilization efficiency and technology economics.As shown,the steam regeneration could achieve a carbon utilization efficiency of 84.31%,compared to 74.74%for air combustion regeneration.The MTO processes using steam regeneration can essentially achieve the near-zero carbon emission.In addition,light olefins production of the MTO processes using steam regeneration is 12.81%higher than that using air combustion regeneration.In this regard,steam regeneration could be considered as a potential yet promising regeneration method for further MTO processes,showing not only great environmental benefits but also competitive economic performance. 展开更多
关键词 Model Methanol to olefins REGENERATION Greenhouse gas Processes simulation
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Boosting CO_(2) hydrogenation to high-value olefins with highly stable performance over Ba and Na co-modified Fe catalyst 被引量:2
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作者 Joshua Iseoluwa Orege Na Liu +3 位作者 Cederick Cyril Amoo Jian Wei Qingjie Ge Jian Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期614-624,I0014,共12页
CO_(2)hydrogenation has been considered to be a highly promising route for the production of high-value olefins(HVOs)while also mitigating CO_(2)emissions.However,it is challenging to achieve high selectivity and main... CO_(2)hydrogenation has been considered to be a highly promising route for the production of high-value olefins(HVOs)while also mitigating CO_(2)emissions.However,it is challenging to achieve high selectivity and maintain stable performance for HVOs(ethylene,propylene,and linear a-olefins)over a prolonged reaction time due to the difficulty in precise control of carbon coupling and rapid catalyst deactivation.Herein,we present a selective Ba and Na co-modified Fe catalyst enriched with Fe_(5)C_(2)and Fe_(3)C active sites that can boost HVO synthesis with up to 66.1%selectivity at an average CO_(2)conversion of 38%for over 500 h.Compared to traditional NaFe catalyst,the combined effect of Ba and Na additives in the NaBaFe-0.5 catalyst suppressed excess oxidation of FeCxsites by H_(2)O.The absence of Fe3O4phase in the spent NaBaFe-0.5 catalyst reflects the stabilization effect of the co-modifiers on the FeCxsites.This study provides a strategy to design Fe-based catalysts that can be scaled up for the stable synthesis of HVOs from CO_(2)hydrogenation. 展开更多
关键词 CO_(2)hydrogenation High-value olefins Barium additive Iron carbide Catalytic stability
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Targeted Catalytic Cracking to Olefins(TCO):Reaction Mechanism,Production Scheme,and Process Perspectives 被引量:1
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作者 Youhao Xu Yanfen Zuo +3 位作者 Wenjie Yang Xingtian Shu Wei Chen Anmin Zheng 《Engineering》 SCIE EI CAS CSCD 2023年第11期100-109,共10页
Light olefins are important organic building blocks in the chemicals industry.The main low-carbon olefin production methods,such as catalytic cracking and steam cracking,have considerable room for improvement in their... Light olefins are important organic building blocks in the chemicals industry.The main low-carbon olefin production methods,such as catalytic cracking and steam cracking,have considerable room for improvement in their utilization of hydrocarbons.This review provides a thorough overview of recent studies on catalytic cracking,steam cracking,and the conversion of crude oil processes.To maximize the production of light olefins and reduce carbon emissions,the perceived benefits of various technologies are examined.Taking olefin generation and conversion as a link to expand upstream and downstream processes,a targeted catalytic cracking to olefins(TCO)process is proposed to meet current demands for the transformation of oil refining into chemical production.The main innovations of this process include a multiple feedstock supply,the development of medium-sized catalysts,and a diameter-transformed fluidizedbed reactor with different feeding schemes.In combination with other chemical processes,TCO is expected to play a critical role in enabling petroleum refining and chemical processes to achieve low carbon dioxide emissions. 展开更多
关键词 Light olefins Steam cracking Catalytic cracking TCO process Oil processing revolution
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Fischer-Tropsch wax catalytic cracking for the production of low olefin and high octane number gasoline: Process optimization and heat effect calculation
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作者 Mei Yang Gang Wang +2 位作者 Jian-Nian Han Cheng-Di Gao Jin-Sen Gao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1255-1265,共11页
To produce low olefin gasoline with high octane number by Fischer-Tropsch (F-T) wax fluid catalytic cracking (FCC) process, operating conditions optimization were carried out in the pilot-scale riser and turbulent flu... To produce low olefin gasoline with high octane number by Fischer-Tropsch (F-T) wax fluid catalytic cracking (FCC) process, operating conditions optimization were carried out in the pilot-scale riser and turbulent fluidized bed (TFB) FCC unit. The experimental results in the riser indicated that under the condition of low reaction temperature and regenerated catalyst temperature, large catalyst-to-oil weight ratio (C/O) and long reaction time, the gasoline olefin content could be reduced to 20.28 wt%, but there is large octane number loss owing to a great loss in high octane number olefin. Therefore, a novel FCC process using the TFB reactor was proposed to strengthen the aromatization reaction. The reaction performance of TFB reactor were investigated. The result demonstrated that the TFB reactor has more significant effect in reducing olefins and improving aromatics. At the expense of certain gasoline yield, the gasoline olefin content reduced to 23.70 wt%, aromatics content could increase to 26.79 wt% and the RON was up to 91.0. The comparison of reactor structure and fluidization demonstrated that the TFB reactor has higher catalyst bed density. The reaction heat and coke combustion heat was calculated indicating the feasibility of its industrial application of the TFB process. 展开更多
关键词 Fischer-Tropsch wax Catalytic cracking RISER TFB Gasoline olefin Reaction heat
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Reaction characteristics of maximizing light olefins and decreasing methane in C_(5) hydrocarbons catalytic pyrolysis
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作者 Mei-Jia Liu Gang Wang +3 位作者 Shun-Nian Xu Tao-Ran Zheng Zhong-Dong Zhang Sheng-Bao He 《Petroleum Science》 SCIE EI CAS CSCD 2023年第3期1909-1921,共13页
When converting C_(5) hydrocarbons to light olefins by catalytic pyrolysis,the generation of low value-added methane will affect the atomic utilization efficiency of C_(5) hydrocarbons.To improve the atomic utilizatio... When converting C_(5) hydrocarbons to light olefins by catalytic pyrolysis,the generation of low value-added methane will affect the atomic utilization efficiency of C_(5) hydrocarbons.To improve the atomic utilization efficiency,different generation pathways of light olefins and methane in the catalytic pyrolysis of C_(5) hydrocarbons were analyzed,and the effects of reaction conditions and zeolite types were inves-tigated.Results showed that light olefins were mainly formed by breaking the C_(2)-C_(3) bond in the middle position,while methane was formed by breaking the C_(1)-C_(2) bond at the end.Meanwhile,it was discovered that the hydrogen transfer reaction could be reduced by about 90%by selecting MTT zeolite with 1D topology and FER zeolite with 2D topology under high weight hourly space velocity(WHSV)and high temperature operations,thus leading to the improvement of the light olefins selectivity for the catalytic pyrolysis of n-pentane and 1-pentene to 55.12% and 74.60%,respectively.Moreover,the fraction ratio of terminal C_(1)-C_(2) bond cleavage was reduced,which would reduce the selectivity of methane to 6.63%and 1.83%.Therefore,zeolite with low hydrogen transfer activity and catalytic pyrolysis process with high WHsV will be conducive to maximize light olefins and to decrease methane. 展开更多
关键词 N-PENTANE 1-Pentene Catalytic pyrolysis Light olefins METHANE
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Long-Chain Gemini Surfactant-Assisted Blade Coating Enables Large-Area Carbon-Based Perovskite Solar Modules with Record Performance
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作者 Yumin Ren Kai Zhang +5 位作者 Zedong Lin Xiaozhen Wei Man Xu Xianzhen Huang Haining Chen Shihe Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期463-477,共15页
Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air.However,scaling up to high-efficiency carbon-based solar modules hinges on reliable dep... Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air.However,scaling up to high-efficiency carbon-based solar modules hinges on reliable deposition of uniform defect-free perovskite films over large areas,which is an unsettled but urgent issue.In this work,a long-chain gemini surfactant is introduced into perovskite precursor ink to enforce self-assembly into a network structure,considerably enhancing the coverage and smoothness of the perovskite films.The long gemini surfactant plays a distinctively synergistic role in perovskite film construction,crystallization kinetics modulation and defect passivation,leading to a certified record power conversion efficiency of 15.46%with Voc of 1.13 V and Jsc of 22.92 mA cm^(-2)for this type of modules.Importantly,all of the functional layers of the module are printed through a simple and high-speed(300 cm min^(-1))blade coating strategy in ambient atmosphere.These results mark a significant step toward the commercialization of all-printable carbon-based perovskite solar modules. 展开更多
关键词 long-chain gemini surfactant Blade-coating Capillary number Carbon-based perovskite photovoltaics All-printable module
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Study on the epoxidation of olefins with H_(2)O_(2)catalyzed by biquaternary ammonium phosphotungstic acid
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作者 Zijie Zhang Qianyu Zha +3 位作者 Ying Liu Zhibing Zhang Jia Liu Zheng Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第6期146-154,共9页
Selective epoxidation of olefins is an important field in chemical industry.In this work,we developed a new phosphotungstic acid catalyst{[(C_8H_(17))(CH_(3))_(2)N]_(2)(CH_(2))_(3)}_(1.5){PO_(4)[WO(O_(2))_(2)]_(4)}wit... Selective epoxidation of olefins is an important field in chemical industry.In this work,we developed a new phosphotungstic acid catalyst{[(C_8H_(17))(CH_(3))_(2)N]_(2)(CH_(2))_(3)}_(1.5){PO_(4)[WO(O_(2))_(2)]_(4)}with long carbon chain and biquaternary ammonium cation.Cyclohexene could be epoxidized to cyclohexene oxide in 96.3%conversion and 98.2%selectivity.The catalyst type,solvent type,catalyst loading,initial molar ratio,temperature,cycle performance and substrate extensibility were studied and optimized,the kinetic parameters about overall reaction and unit reaction were also calculated.Dynamic light scattering analysis was carried out to explain the different catalytic performance between catalysts with different carbon chain length.This novel catalyst and the corresponding dynamics and mechanism study could probably help the industrial application on the epoxidation of cyclohexene with H_(2)O_(2). 展开更多
关键词 Epoxidation of olefins Phosphotungstic acid CYCLOHEXENE Kinetic study
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Haplotype analysis of long-chain non-coding RNA NONHSAT102891 promoter polymorphisms and depression in Chinese individuals: A case-control association study
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作者 Yue Li Yi-Xi Wang +5 位作者 Xing-Ming Tang Peng Liang Jing-Jie Chen Feng Jiang Qiang Yang Yun-Dan Liang 《World Journal of Psychiatry》 SCIE 2023年第12期1005-1015,共11页
BACKGROUND Our previous study reported that the single-nucleotide polymorphism(SNP)rs155979 GC in the promoter region of long-chain non-coding RNA(lncRNA)NONHSAT102891 affects depression susceptibility in a Chinese po... BACKGROUND Our previous study reported that the single-nucleotide polymorphism(SNP)rs155979 GC in the promoter region of long-chain non-coding RNA(lncRNA)NONHSAT102891 affects depression susceptibility in a Chinese population.AIM To explored associations of two SNPs and haplotypes in the lncRNA NONHSAT102891 promoter region with depression susceptibility in Chinese population.METHODS This this case-control association study was approved by the Ethics Committee of Chengdu Medical College(approval number:201815).Patient diagnosis was based on DSM-IV criteria.We selected a total of 480 patients with depression and 329 healthy controls with no history of psychopathology,and performed genotyping of two SNPs by extracting peripheral venous blood samples from the subjects.The function of the two lncRNA NONHSAT102891 promoter G/C and A/T haplotypes was detected by dual-luciferase reporter assays of human embryonic kidney 293T transfected cells.RESULTS Stratified analysis of clinical and genotypic characteristics of our cohort showed that the degree of mild depressive episodes associated with the rs6230 TC/CC genotype increased by 1.59 times[TC/CC vs TT:odds ratio(OR)=1.59,95%confidence interval(CI):1.08-2.35,P=0.019].The haploid analysis revealed linkage disequilibrium between rs3792747 and rs6230,and the double SNP CG haplotype was more common in the control group compared to case group,indicating that this haplotype significantly reduced the risk of depression(C/G vs T/A:OR=0.42,95%CI:0.21-0.83,P=0.01).There was no significant difference in the dual-luciferase reporter activity of the G/C and A/T haplotypes compared with the control group(P>0.05),indicating that the double SNP haplotype has no transcrip-tional activity.CONCLUSION The rs3792747 and rs6230 CG haplotypes of the lncRNA NONHSA T102891 promoter may be related to a reduced risk of depression in the Han Chinese population. 展开更多
关键词 long-chain non-coding RNA NONHSAT102891 DEPRESSION SUSCEPTIBILITY Single-nucleotide polymorphisms HAPLOTYPE Transcriptional activity
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Production of linear alkylbenzene over Ce containing Beta zeolites
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作者 Shiqi Zhang Shengzhi Gan +1 位作者 Baoyu Liu Jinxiang Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期220-227,共8页
Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na species.Additional citric acid can effectively prevent the deposition of Ce species dur... Ce-encapsulated Beta zeolite was synthesized by a one-pot hydrothermal method with citric acid complexing Ce in the absence of Na species.Additional citric acid can effectively prevent the deposition of Ce species during the hydrothermal synthesis of zeolites,leading to uniform distribution of Ce cluster in the framework of Beta zeolites.Moreover,the sodium-free synthesis system resulted that the Brønsted acid sites were mainly located on the straight channels and external surface of Beta zeolites,improving the utilization of Brønsted acid sites.In addition,Ce encapsulated Beta zeolites showed enhanced activity and robust stability in the alkylation of benzene with 1-dodecene based on the synergistic effect between Ce species and Brønsted acid sites,which pave the way for its practical application in the production of alkylbenzene. 展开更多
关键词 Beta zeolites CATALYSIS ALKYLATION long-chain olefins
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国内首套ORP除烯烃装置的工艺及应用研究 被引量:1
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作者 王鹏 《现代化工》 CAS CSCD 北大核心 2024年第1期230-233,共4页
美国UOP公司新研制的ORP除烯烃装置首次在中国石油广东石化公司260万t/a芳烃联合装置进行了工业应用。该装置用于脱除重整上游重整生成油中的烯烃,在45~110℃工作温度、2.1 MPa操作压力、5.0质量空速条件下,可满足下游吸附分离单元对进料... 美国UOP公司新研制的ORP除烯烃装置首次在中国石油广东石化公司260万t/a芳烃联合装置进行了工业应用。该装置用于脱除重整上游重整生成油中的烯烃,在45~110℃工作温度、2.1 MPa操作压力、5.0质量空速条件下,可满足下游吸附分离单元对进料中溴指数低于20×10^(-6)的进料要求。通过与传统的酸性白土吸附工艺的对比,分析其工艺、操作、参数和配备设施等情况,研究表明,该ORP除烯烃装置具有低生产成本、催化剂可在线再生、大幅降低固废产生、可根据不同生产状况及时进行调整等优点。 展开更多
关键词 芳烃联合装置 ORP 白土吸附 烯烃
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基质Lewis酸性调控及其催化轻烃裂化反应性能
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作者 冯锐 方舟 +4 位作者 周鹏 李天泊 胡晓燕 闫新龙 张忠东 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第2期218-233,共16页
催化剂分子筛和基质的合理匹配是提高石脑油催化裂化制低碳烯烃产量的最有效路径之一,但是基质表面Lewis酸性对裂化反应的影响尚未明确。本研究通过硼和锌改性γ-Al_(2)O_(3)和锡改性KIT-6介孔氧化硅材料调变表面的Lewis酸,研究基质及其... 催化剂分子筛和基质的合理匹配是提高石脑油催化裂化制低碳烯烃产量的最有效路径之一,但是基质表面Lewis酸性对裂化反应的影响尚未明确。本研究通过硼和锌改性γ-Al_(2)O_(3)和锡改性KIT-6介孔氧化硅材料调变表面的Lewis酸,研究基质及其与ZSM-5分子筛配合使用时催化正庚烷和1-己烯裂化制低碳烯烃的性能。采用XRD、TEM、N2物理吸附-脱附以及NH3-TPD等方法探讨了改性γ-Al_(2)O_(3)和KIT-6的结构性质和表面酸性质。结果表明,B可以降低γ-Al_(2)O_(3)的表面Lewis酸性(酸量和酸强度),而Zn可以增强其表面酸性;此外,Sn可以提高有序介孔KIT-6表面Lewis酸性。催化裂化反应结果表明,当基质单独使用时,随基质表面Lewis酸性增强,轻烃反应活化能降低且转化率升高;当基质与ZSM-5配合使用时,基质在上分子筛在下的双床层排布方式对应的转化率最高,且随基质Lewis酸性增强,轻烃转化率升高,但Lewis酸性过强会加速氢转移反应,降低低碳烯烃的选择性。 展开更多
关键词 路易斯酸 基质 催化裂化 低碳烯烃
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C_(4)烯烃转化制丙烯工艺及催化剂研究
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作者 饶维 刘晨 《石油与天然气化工》 CAS CSCD 北大核心 2024年第2期39-46,共8页
目的开发C_(4)烯烃催化裂解制丙烯工艺和催化剂制备工艺技术,完成小试和工业侧线试验。方法采用固定床评价装置考查了催化剂配方、改性及工业条件对催化剂活性、选择性、稳定性能的影响。结果以ZSM-5分子筛为活性组分的催化剂在C_(4)烯... 目的开发C_(4)烯烃催化裂解制丙烯工艺和催化剂制备工艺技术,完成小试和工业侧线试验。方法采用固定床评价装置考查了催化剂配方、改性及工业条件对催化剂活性、选择性、稳定性能的影响。结果以ZSM-5分子筛为活性组分的催化剂在C_(4)烯烃转化制丙烯反应中具有较好的活性、选择性、稳定性和再生性,磷的引入未改变催化剂的晶型结构,但降低了催化剂酸性位点数量,并调节了催化剂的n(B酸)/n(L酸),随着磷负载量增加到5%(w),分子筛中磷与铝的相互作用逐渐增强,磷可以和骨架铝和非骨架铝相互作用。结论C_(4)烯烃的转化率达到80%以上,丙烯的选择性达到35%~45%,催化剂的单程寿命达到一个月以上,且经再生后,再生恢复率达95%。 展开更多
关键词 C_(4)烯烃 催化裂解 ZSM-5分子筛 催化剂活性 丙烯
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快速合成Cu-SAPO-34分子筛及其甲醇制烯烃催化性能
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作者 张强 周洲 +2 位作者 李建祥 田梦阳 于梦云 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期197-205,共9页
通过引入含铜分子筛晶种作为铜源、10 h快速合成出Cu-SAPO-34分子筛,并与传统的水热合成法和铜胺络合物引入铜源的方式进行对比,同时利用XRD、SEM、IR、TPD和微反等手段表征样品的结构和甲醇制烯烃(MTO)催化性能。结果表明:与常规合成... 通过引入含铜分子筛晶种作为铜源、10 h快速合成出Cu-SAPO-34分子筛,并与传统的水热合成法和铜胺络合物引入铜源的方式进行对比,同时利用XRD、SEM、IR、TPD和微反等手段表征样品的结构和甲醇制烯烃(MTO)催化性能。结果表明:与常规合成方法相比,快速合成法可在10 h制备出结晶度在86.24%,固体收率达到94.65%的Cu-SAPO-34分子筛,其乙烯+丙烯选择之和达到81.26%;与添加铜胺络合物相比,加入含铜分子筛晶种的方式引入铜元素,更合适于快速合成法,避免了铜无法与分子筛骨架结合的问题;通过调整含铜分子筛晶种的性质及加入量,可以快速合成晶粒直径在470 nm的纳米Cu-SAPO-34分子筛,固体收率达到96.72%,乙烯+丙烯选择之和达到86.24%。 展开更多
关键词 甲醇制烯烃 Cu-SAPO-34分子筛 快速合成 含铜分子筛晶种
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烯式吡虫啉(olefin IMI)光解及其光解产物研究 被引量:1
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作者 葛峰 单正军 +2 位作者 戴亦军 陈婷 袁生 《生态与农村环境学报》 CAS CSSCI CSCD 北大核心 2009年第2期103-106,共4页
烟碱类杀虫剂吡虫啉(imidacloprid,IMI)在环境中可代谢为生物活性提高10倍的烯式吡虫啉(olefin IMI)。研究了olefin IMI的光稳定性、光解动力学和光解代谢途径。结果表明:olefin IMI在避光条件下较为稳定,室温下放置400d后,olefin IMI... 烟碱类杀虫剂吡虫啉(imidacloprid,IMI)在环境中可代谢为生物活性提高10倍的烯式吡虫啉(olefin IMI)。研究了olefin IMI的光稳定性、光解动力学和光解代谢途径。结果表明:olefin IMI在避光条件下较为稳定,室温下放置400d后,olefin IMI含量仅减少3%;而在室内模拟日光条件下,olefin IMI易于分解,光解反应符合一级动力学方程(r>0.99),半衰期为4d。olefin IMI的光解反应存在2条主要途径:一是羟基化生成4,5-二羟基化吡虫啉,该产物进一步氧化断裂药效基团硝基亚胺基生成羰基化产物;二是直接脱去硝基基团生成胍基产物。 展开更多
关键词 烯式吡虫啉(olefin IMI) 光解 代谢途径
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离子液体在烯烃羰基化反应中的应用
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作者 赵敏 郭岩锋 +2 位作者 贾庆龙 王莹 朱向春 《石油化工》 CAS CSCD 北大核心 2024年第1期115-120,共6页
烯烃羰基化反应是指在过渡金属催化剂存在条件下,将CO或者CO_(2)分子以羰基的形式插入到烯烃与亲核试剂(H_(2)、醇、水)中,合成具有更高附加值的化学品的过程。该过程通常是在均相体系中进行,增加了催化剂分离成本。利用离子液体(IL)蒸... 烯烃羰基化反应是指在过渡金属催化剂存在条件下,将CO或者CO_(2)分子以羰基的形式插入到烯烃与亲核试剂(H_(2)、醇、水)中,合成具有更高附加值的化学品的过程。该过程通常是在均相体系中进行,增加了催化剂分离成本。利用离子液体(IL)蒸气压极低和极性可调的特点,能够简化羰基化反应中催化剂与原料及产物的分离过程,是一种绿色、可循环的催化剂分离和回收方式。综述了IL在烯烃羰基化反应中的研究进展,并对IL在烯烃羰基化反应中存在的问题及未来发展方向进行了探讨。 展开更多
关键词 离子液体 烯烃 羰基化 双相体系 催化剂回收
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铑基非均相催化剂在烯烃氢甲酰化反应中的应用研究进展
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作者 陈万 孙功成 +4 位作者 张勇 李尧莹 范素兵 吕俊敏 赵天生 《低碳化学与化工》 CAS 北大核心 2024年第3期18-29,共12页
烯烃氢甲酰化反应是工业中合成醛的重要过程,铑基均相催化剂难以回收的缺点会大大增加烯烃氢甲酰化反应的成本。负载固相多相催化剂因其简便的分离循环操作而广受关注,但存在反应活性较差、金属流失量较大和催化剂制备成本较高等问题,... 烯烃氢甲酰化反应是工业中合成醛的重要过程,铑基均相催化剂难以回收的缺点会大大增加烯烃氢甲酰化反应的成本。负载固相多相催化剂因其简便的分离循环操作而广受关注,但存在反应活性较差、金属流失量较大和催化剂制备成本较高等问题,开发催化性能和回收性能好的非均相铑基催化剂具有广阔的前景。以无机固体载体固定化催化剂、HRh(CO)(PPh_(3))_(3)封装型多相催化剂、多孔有机配体(POL)材料负载催化剂和单原子金属间纳米催化剂这4类催化剂为主线,综述了用于烯烃氢甲酰化反应中多相负载型铑基催化剂的研究进展。在多相负载型铑基催化剂中,膦配体组成及制备条件、载体种类及性质和铑与其他金属协同作用等均能对其催化烯烃氢甲酰化反应的催化性能产生影响,对上述4类催化剂的优、缺点和发展前景进行了简要分析。在今后的研究中,建议设计给电子能力强、空间位阻大的膦配体,发掘高比表面积、多级孔道结构的无机/有机载体,深入探究金属纳米粒子间的相互作用,进一步提高铑基催化剂在烯烃氢甲酰化中的催化性能和回收性能。 展开更多
关键词 烯烃 氢甲酰化 非均相催化剂 铑基催化剂
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Co/SAPO-34催化剂在MTO反应中催化性能和积炭行为
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作者 李宁 褚睿智 +6 位作者 吴佳欣 孟献梁 吴国光 李晓 李伟松 江晓凤 俞时 《洁净煤技术》 CAS CSCD 北大核心 2024年第1期66-75,共10页
针对SAPO-34分子筛在MTO反应中烯烃选择性低和易于酸性积炭失活的问题,通过等体积浸渍法向SAPO-34分子筛孔道内引入金属Co,系统考察了Co的加入量对Co/SAPO-34催化剂在MTO反应中的催化性能和积炭行为的影响。结果表明金属Co可以作为脱氢... 针对SAPO-34分子筛在MTO反应中烯烃选择性低和易于酸性积炭失活的问题,通过等体积浸渍法向SAPO-34分子筛孔道内引入金属Co,系统考察了Co的加入量对Co/SAPO-34催化剂在MTO反应中的催化性能和积炭行为的影响。结果表明金属Co可以作为脱氢反应中心位点,削弱氢离子转移作用,抑制烷烃的生成,进而有效提高反应烯烃选择性;同时Co金属的引入可以精密调控SAPO-34分子筛表面酸中心强度,提高弱酸/强酸比例,进而削弱强酸中心的积炭作用,抑制催化剂的积炭失活。结合NH_(3)-TPD、H_(2)-TPD、氮气物理吸脱附、TG、XPS、GC-MS等表征方法,深入探讨Co/SAPO-34催化剂在MTO反应中的积炭行为,发现多甲基苯类关键积炭前体优先沉积于微孔和强酸位点,并显著促进稠环芳烃的生成,而相对较大的孔体积以及适量的弱酸浓度可以协同促进积炭前体的分解转化,抑制稠环芳烃等硬积炭物种的形成。积炭速率计算表明,具有适量酸性和孔道结构的Co 0.5/SAPO-34的甲醇转化率及低碳烯烃选择性最高,催化寿命最长。 展开更多
关键词 Co/SAPO-34 浸渍 甲醇制烯烃 积炭 失活 选择性
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四环十二碳烯工艺进展
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作者 陈麒全 傅建松 +1 位作者 曹强 沈崇润 《化学反应工程与工艺》 CAS 2024年第2期186-192,共7页
本文综述了四环十二碳烯的制备方法、合成工艺优化和市场前景。四环十二碳烯可代替降冰片烯作为环烯烃单体,用于生产环烯烃共聚物(COC)和环烯烃聚合物(COP),使其拥有更高的玻璃化转变温度和更强的韧性。四环十二碳烯的合成原料为双环戊... 本文综述了四环十二碳烯的制备方法、合成工艺优化和市场前景。四环十二碳烯可代替降冰片烯作为环烯烃单体,用于生产环烯烃共聚物(COC)和环烯烃聚合物(COP),使其拥有更高的玻璃化转变温度和更强的韧性。四环十二碳烯的合成原料为双环戊二烯、降冰片烯和乙烯,通过Diels-Alder反应在高温和高压的条件下制备。四环十二碳烯的合成工艺包括反应工段和精馏工段,本文从降低或除去副产物和防止降冰片烯在管道中凝固两个方向介绍了国内外工艺改进方法。最后,结合国际和国内市场现状,分析了四环十二碳烯的市场前景,同时也提出未来的工艺优化方向。 展开更多
关键词 四环十二碳烯 环烯烃共聚物 降冰片烯 双环戊二烯
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电容层析成像测量甲醇制烯烃催化剂床层温度
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作者 陈锡岳 孟霜鹤 +1 位作者 张涛 叶茂 《洁净煤技术》 CAS CSCD 北大核心 2024年第5期136-143,共8页
甲醇制烯烃作为煤制烯烃的关键一环,对实现煤炭的综合利用有重要意义。这一过程是典型的放热反应,为提高甲醇转化率与产物选择性,需对床层温度进行在线监测。基于高温电容层析成像,提出一种在线测量催化剂床层温度(DMTO工业催化剂,ZSM-... 甲醇制烯烃作为煤制烯烃的关键一环,对实现煤炭的综合利用有重要意义。这一过程是典型的放热反应,为提高甲醇转化率与产物选择性,需对床层温度进行在线监测。基于高温电容层析成像,提出一种在线测量催化剂床层温度(DMTO工业催化剂,ZSM-5分子筛)的方法。通过与介电常数变化极小的石英砂、氧化铝等床层材料的测量结果对比,发现不同催化剂的介电常数随温度变化规律不同,催化剂床层的测量电容值随温度变化敏感且重复性较好。因此可通过高温电容层析成像装置测量温度分布均匀的床层归一化电容平均值实现对床层温度的测量。通过采用薄壁石英管的固定反应器,对甲醇制烯烃催化剂、ZSM-5分子床层进行在线测温验证了该方法的有效性,发现通过线性反投影算法重构的ECTt图像,可获得床层温度分布。由此,可以通过高温电容层析成像装置实现对固定床床层床层测温。 展开更多
关键词 甲醇制烯烃 分子筛催化剂 在线测量 电容层析成像 温度
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煅烧温度对ZnGaZrO_(x)/SAPO-34催化性能的影响
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作者 杨坤 任启霞 +3 位作者 董永刚 刘飞 姚梦琴 曹建新 《无机盐工业》 CAS CSCD 北大核心 2024年第2期136-145,共10页
在CO_(2)加氢制低碳烯烃(C_(2)^(=)-C_(4)^(=))中,双功能催化剂的煅烧温度对其催化性能具有显著影响。基于此,采用共沉淀法制备了ZnGaZrO_(x)氧化物,水热法制备了SAPO-34分子筛,然后对两者进行研磨制得ZnGaZrO_(x)/SAPO-34双功能催化剂... 在CO_(2)加氢制低碳烯烃(C_(2)^(=)-C_(4)^(=))中,双功能催化剂的煅烧温度对其催化性能具有显著影响。基于此,采用共沉淀法制备了ZnGaZrO_(x)氧化物,水热法制备了SAPO-34分子筛,然后对两者进行研磨制得ZnGaZrO_(x)/SAPO-34双功能催化剂,并考察煅烧温度对ZnGaZrO_(x)和SAPO-34物化性质及催化性能的影响。通过XRD、XPS、H_(2)/CO_(2)/NH_(3)-TPD、SEM、N_(2)吸附-脱附和原位DRIFTS表征发现,在制备ZnGaZrO_(x)过程中,当煅烧温度为650℃时,ZnGaZrO_(x)具有最强的H_(2)和CO_(2)吸附活化能力,能有效提高HCOO*和CH_(3)O*的生成速率和浓度,促进甲醇产物生成;在制备SAPO-34过程中,当煅烧温度为450℃时,分子筛比表面积最大、晶粒尺寸最小、强酸位点的酸性最弱,能有效避免低碳烯烃发生二次加氢,从而获得较高的低碳烯烃选择性。最佳条件下合成的ZnGaZrO_(x)/SAPO-34双功能催化剂在反应温度为390℃、压力为3 MPa、空速为3600 mL/(g∙h)条件下,CO_(2)转化率为28.3%,CO选择性仅为44.6%,C_(2)^(=)-C_(4)^(=)选择性为84.4%,C_(2)^(=)-C_(4)^(=)产率高达13.2%,且在反应100 h内催化性能无明显衰减。该工作为双功能催化剂的改性提供了新的研究思路。 展开更多
关键词 CO_(2)加氢 低碳烯烃 煅烧温度 氧空位 酸性
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