Selective oxidation of cyclopentene with H_2O_2 by using H_3PW_(12)O_(40) and TBAB as a phase transfer catalyst

The selective oxidation of cyclopentene by aqueous H_2O_2 using H_3PW_(12)O_(40) and tetrabutyl ammonium bromide(TBAB) as a phase transfer catalyst has been investigated. The results show that the presence of TBAB significantly improved the oxidation selectivity of cyclopentene. The effects of the reaction conditions on the conversion of cyclopentene were investigated in detail. The optimal reaction conditions are as follows: the H_3PW_(12)O_(40) to TBAB molar ratio, 1:1–1:3; H_3PW_(12)O_(40) to cyclopentene molar ratio,0.54:100–0.64:100; and molar ratio of H_2O_2 to cyclopentene, 1.6:1. The conversion reached to 59.8% in 4h at 35.0 °C, while the selectivity of glutaraldehyde was 38.0% and the selectivity of 1,2-cyclopentanediol was 55.6%. In addition, a route for oxidation of cyclopentene by aqueous H_2O_2 using a heteropoly acid and quaternary ammonium salt as a phase transfer catalyst was proposed.     

Lipase-catalyzed Synthesis of Caffeic Acid Phenethyl Ester in Ionic Liquids： Effect of Specific Ions and Reaction Parameters

Caffeic acid phenethyl ester（CAPE） is a rare, naturally occurring phenolic food additive. This work systematically reported fundamental data on conversion of caffeic acid（CA）, yield of CAPE, and reactive selectivity during the lipase-catalyzed esterification process of CA and phenylethanol（PE） in ionic liquids（ILs）. Sixteen ILs were selected as the reaction media, and the relative lipase-catalyzed synthesis properties of CAPE were measured in an effort to enhance the yield of CAPE with high selectivity. The results indicated that ILs containing weakly coordinating anions and cations with adequate alkyl chain length improved the synthesis of CAPE. [Emim][Tf2 N] was selected as the optimal reaction media. The optimal parameters were as follows by response surface methodology（RSM）： reaction temperature, 84.0 °C; mass ratio of Novozym 435 to CA, 14︰1; and molar ratio of PE to CA, 16 ︰ 1. The highest reactive selectivity of CAPE catalyzed by Novozym 435 in [Emim][Tf2 N] reached 64.55%（CA conversion 98.76% and CAPE yield 63.75%, respectively）. Thus, lipase-catalyzed esterification in ILs is a promising method suitable for CAPE production.     

反应沉淀法制备超细硫酸沙丁胺醇颗粒及其粉雾剂的表征

The preparation of ultra-fine particles of salbutamol sulphate （SS） was accomplished with a reactive precipitation pathway, in which salbutamol and sulphuric acid were Used as reactants with the solvents of ethanol.The effects of sulphuric acid concentration, reaction temperature, stirring rate, and reaction time onthesize of the particle were investigated. A binary mixture composed of lactose and SS was prepared to evaluate SS. The results showed that ultra-fine SS particles with controlled diameters ranging between 3 μm and 0.8 μm and with a narrow distribution could be achieved. The morphology consisting of clubbed particles wassuccess.fully obtained. The purity of the particles reached above 98% with-UV detection. The dose- of dry powder inhalation was obtained by blending the particles with recrystallized lactose, which acted as a carrier. The deposition quantity of the drug in breathing tract was estimated using a twin imPinger apparatus. Compared with the Shapuer powder （purchased in the market）, the results showed that SS_particles had more quantifies.subsided in simulative lung.. _     

The influence mechanism of solvent on the hydrogenation of dimethyl oxalate

The hydrogenation of dimethyl oxalate(DMO) for the producing of C2-C4 alcohols with methanol as solvent was researched at the temperature of 270 °C to 310 °C. Ethylene glycol(EG) was the main product at low temperature and the selectivity of which was 61.9% at 230 °C. However, EG selectivity decreased sharply with the increase of temperature while ethanol became the main liquid products with the selectivity of 43.5% at 270 °C. It can be ascribed to a thorough hydrogenation of DMO at a high temperature. In addition, the promotion of Guerbet reaction led to the production of propanol and butanol. Simultaneously, the amount of gas products including CO, CO_2 and dimethyl ether(DME) also increased, which became a competition factor in the conversion of DMO to liquid products including C2-C4 alcohols. The blank test was carried out with pure methanol as feedstock with and without Cu/SiO_2 catalyst, which revealed that methanol was involved in the formation of gas products and higher alcohols on Cu-based catalyst, and the main gas product was CO.     

Extraction of potassium from K-feldspar via the CaCl2 calcination route☆

The extraction of potassium from K-feldspar via a calcium chloride calcination route was studied with a focus on the effects of the calcination atmosphere, calcination temperature and time, mass ratio of CaCl2 to K-feldspar ore and particle size of the K-feldspar ore. The results demonstrated that a competing high-temperature hydrolysis reaction of calcium chloride with moisture in a damp atmosphere occurred concurrently with the conversion reaction of K-feldspar with CaCl2, thus reducing the amount of potassium extracted. The conversion reaction started at approximately 600 °C and accelerated with increasing temperature. When the temperature rose above 900 °C, the extraction of potassium gradually decreased due to the volatilization of the product, KCl. As much as approximately 41%of the potassium was volatilized in 40 min at 1100 °C. The mass ratio of CaCl2/K-feldspar ore significantly affected the extraction. At a mass ratio of 1.15 and 900 °C, the potassium extraction reached 91%in 40 min, while the extraction was reduced to only 22%at the theoretical mass ratio of 0.2. Optimal process conditions are as follows:ore particle size of 50–75μm, tablet forming pressure of 3 MPa, dry nitrogen atmosphere, mass ratio of CaCl2/ore 1.15:1, calcination temperature of 900 °C, and calcination time of 40 min. The XRD analysis revealed that a complex phase transition of the product SiO2 was also accompanied by the con-version reaction of K-feldspar/CaCl2. The SiO2 product formed at the initial stage was in the quartz phase at 900 °C and was gradually transformed into cristobalite after 30 min.     

固定化Candida sp. 99-125脂肪酶催化合成蜡酯(英文)

Wax esters were synthesized in a solvent free system catalyzed by immobilized lipase from Candida sp. 99-125, with oleic acid and cetyl alcohol. The effects of substrate molar ratio, lipase dosage and water removal were investigated in a 50 ml flask incubated in a thermostatic cultivation cabinet. The optimized conditions were: temperature 40 ℃, shaking at 170 r·min-1, acid/alcohol molar ratio 1:0.9, lipase dosage in 10% (by mass) of oleic acid, and open reaction for water removal. As a result, the conversion rate reached 98% for reaction of 8 h. The volume of reactor was scaled up to 1 L three-neck flask. The optimized parameters were: 200 r·min-1 agitation speed, 2.5% (by mass) lipase dosage, others were the same as the parameters described above. The conversion rate reached 95% for reaction of 24 h. The lipase retained 46% conversion rate after reuse for 6, 7 batches. The products were purified by removing remained cetyl alcohol and fatty acids with ethanol and saturated sodium carbonate so-lution, respectively. The purity of the wax ester, cetyl oleate, was 96%. The physical and chemical properties of cetyl oleate were tested and compared with those of jojoba oil. The results show that the product cetyl oleate has great potential to use as the substitute of natural jojoba oil.     

[bmin]Cl/[FeCl3]离子液体催化的苯与1-十八烯烷基化反应

Abstract The study on the catalysis of ionic liquids for alkylation of benzene with 1-octadecene to synthesize LAB （linear alkylbenzenes） was performed. The results showed that the most important factor that governed the conversion of olefin and selectivity of LAB was reaction temperature. Moreover, the effects of different ionic liquids and molar ratio of benzene to 1-octadecene on the conversion and selectivity were obviously in different degrees. The reaction temperature, molar ratio of benzene to 1-octadecene and the amount of catalyst were lower, compared with the traditional reaction technologies. The experimental results demonstrated that the ionic liquid had higher activity at 30℃, with over 98% selectivity of monoalkylbenzene and 100% conversion of the olefin at the molar ratio 0.08 of FeCl3 in ionic liquid to 1-octadecene and 10 for benzene to 1-octadecene.     

1,6-己二胺与氨基甲酸甲酯非均相CeO2催化合成1,6-己二氨基甲酸甲酯（英文）

The efficient synthesis of dimethylhexane-1,6-dicarbamate (HDC) from 1,6-hexanediamine (HDA) and methyl carbonate over a series of heterogeneous catalysts (e.g., MgO, Fe2O3, Mo2O3, and CeO2) was investigated. The reaction pathway was confirmed as an alcoholysis reaction through a series of designed experiments. Under optimized conditions, 100%HDA conversion with 83.1%HDCtotal and 16.9%polyurea was obtained using a one-step with high temperature procedure with CeO2 as the catalyst. A new two-step with variable temperature technol-ogy was developed based on the reaction pathway to reduce the polyurea yield. Using the proposed method, the HDCtotal yield reached 95.2%, whereas the polyurea yield decreased to 4.8%. The CeO2 catalyst showed high stability and did not exhibit any observable decrease in the HDC yield or any structural changes after four recycling periods. ? 2014 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. Al rights reserved.     

甲苯液相空气氧化过程中[Co2+]/[Co3+]的测定及其对反应的影响

Liquid phase oxidation of toluene is an environmental benign route for the production of benzoic acid. In a mm bubble column reactor, the commercial process of toluene liquid phase oxidation was conducted with Co(CH3COO)2&#8226;4H2O as catalyst. The Co2+ concentration [Co2+] was determined by extraction spectrophotometry and hereby the Co3+ concentration [Co3+] was obtained by mass balance. The results showed that [Co3+] reached the maximum at about 25-30 min. [Co3+] increased with increasing Co catalyst amount at total Co concentration <150 mg&#8226;L－1 of toluene. The conversion of toluene, yield and selectivity of benzoic acid increased with the increasing [Co3+/Co2+]max. A high [Co3+] and a high [Co3+]/[Co2+] ratio are beneficial to the reaction.     

The Intermetallic Catalysts for Oxidative Esterification of Methacrolein to Methyl Methacrylate

A series of supported intermetallic Pb-Pb catalysts were prepared with the impregnation method by changing the support (silica, molecular sieve or g-alumina ) and the pore size. The chemical states of the two metals were characterized by XPS analysis, the process for producing methyl methacrylate based on the direct oxidative esterification of methacrolein with methanol in the presence of oxygen was performed in a slurry reactor with the above-mentioned catalysts. The influence of the calcination temperature and the kinds of support as well as the pore size on catalytic activity had been extensively investigated. Under the conditions of temperature at 80℃, catalyst 3.8% (w) and the reaction time 2 h, the conversion rate of methacrolein reached 85%, the selectivity and the yield of methyl methacrylate were 90% and 76.5%, respectively.     

高剪切反应器中对叔丁基甲苯氧化过程的研究

高剪切反应器能够高效地将一相或多相反应物均匀分布到另一个连续相中,瞬间实现多相反应物的微米级混合,加快反应速度,提高原料利用率。文中以原料对叔丁基甲苯(PTBT)自身为溶剂,氧气为氧化剂,醋酸钴为催化剂,反应产物对叔丁基苯甲酸(PTBBA)为引发剂,在高剪切反应器中常压合成对叔丁基苯甲酸。结果表明:高剪切可显著提高反应的转化率与选择性,缩短反应时间,所得适宜的氧化条件:反应温度160℃,反应5 h后,其收率为56.8%,选择性为92.1%。确定了160℃时PTBT氧化过程为一级反应,反应速率仅与对叔丁基甲苯的浓度有关,速率常数k=4.10×10-3min-1。     

Co/γ-Al2O3催化乙酰丙酸加氢合成γ-戊内酯的研究

采用等体积浸渍法制备一系列Co负载量不同的Co/Al₂O₃催化剂,用于乙酰丙酸液相催化加氢制γ-戊内酯反应。采用X射线衍射仪和透射电镜对Co/Al₂O₃催化剂进行表征,考察Co负载量、反应温度、反应压力和催化剂用量等对乙酰丙酸液相催化加氢反应的影响。结果表明,在Co负载质量分数15%、反应温度140 ℃、反应压力4.0 MPa和催化剂用量为反应物总质量的20%条件下,以甲醇为溶剂,反应6 h,乙酰丙酸转化率100%,γ-戊内酯选择性80.4%。催化剂重复使用6次仍具有较好的催化性能。     

不同原料加氢催化裂解制取液化石油气

选择正己烷、正庚烷以及不同终馏点直馏汽油作为反应物,用负载金属活性组分的双功能加氢裂解催化剂进行制取液化石油气的考察。结果表明,在双功能加氢裂解催化剂存在下,正庚烷加氢催化裂解制取液化石油气的转化率较正己烷高,超过59%,而选择性相差不大。终馏点180 ℃直馏汽油气体收率、液化石油气对气体的选择性、液化石油气对原料的收率分别为68.17%、45.69%和31.14%,均比终馏点190 ℃直馏汽油高（分别为53.37%、39.37%和21.01%）。     

微通道中环己酮氧化合成ε-己内酯的连续流工艺

在微通道反应器中,由H2O2、乙酸酐反应连续合成过氧乙酸氧化剂,再与环己酮经Baeyer-Villiger氧化连续合成ε-己内酯。先后考察了过氧乙酸氧化剂合成中乙酸酐与H2O2摩尔比、反应温度、停留时间等因素的影响,环己酮氧化反应中原料摩尔配比、反应温度、停留时间等因素对ε-己内酯合成的影响,优化了工艺条件。结果表明,当n(乙酸酐)∶n(H2O2)=1.2∶1、反应温度为70℃、停留时间为115s时,H2O2转化率达88.9%,过氧乙酸收率达86.7%;当n(过氧乙酸)∶n(环己酮)=1.1∶1、反应温度为90℃、停留时间为90s时,环己酮转化率达96.2%,ε-己内酯的收率达80.9%。与传统间歇釜式反应工艺相比,微通道反应工艺提高了ε-己内酯的收率和选择性,缩短了反应时间,减少了原料消耗,实现了连续化操作,提高了生产安全性。     

反应温度对催化裂化汽油芳构化的研究

以中国石油兰州炼油石化公司催化汽油为原料，采用小型固定流化床为芳构化反应装置，考察了反应温度对芳构化产物收率、转化率、马达法和研究法辛烷值、气体产品组成和液体产品组成的影响规律。实验结果表明，随着反应温度的升高，干气、液化气和焦炭收率呈上升趋势，而汽油和柴油收率呈下降趋势，FCC汽油的转化率都在94%左右，且随反应温度的升高先增大后减小；乙烯、丙烯、丁烯、乙烯和总低碳烯烃收率单调增加，而乙烯、丙烯、丁烯、乙烯和丙烯和总低碳烯烃收率的增加幅度各不相同；异构烷烃和烯烃收率随着反应温度的升高逐渐减少，而芳烃的收率和选择性随着反应温度的升高逐渐增加，正构烷烃和环烷烃的收率随着温度的增加先增加后减少。     

甘油与环己酮缩合反应催化剂的研究

通过比较Lewis酸、质子酸、无机酸酐、分子筛、酸化蒙脱土在催化甘油与环己酮缩合反应中的活性,研究了催化剂结构和性质对环己酮转化率和反应选择性的影响。结果表明,Lewis酸有较高的催化活性和稳定性,而且表现为L酸和B酸两种酸的催化形式。催化剂结构对环己酮转化率和反应选择性的影响为:(1)Lewis酸的构成:对相同阴离子的Lewis酸而言,其阳离子的L酸酸强度越强或水解程度越大,催化活性和2-羟甲基-1,4-二氧杂螺环[4,5]癸烷(产物a)的选择性越高;对相同阳离子的Lewis酸而言,其盐酸盐型的催化活性和产物a的选择性要高于硫酸盐型的;(2)水合硫酸盐的催化活性与其煅烧温度有关。催化活性和产物a的选择性最好的Lewis酸为AlCl3。当n(AlCl3)∶n(环己酮)∶n(甘油)=1∶10 000∶15 000,带水剂环己烷加入量为反应物总体积的47%,92℃回流反应2 h,环己酮转化率为97.9%;最终产物中产物a的选择性为97.8%。     

固体酸催化过氧化氢异丙苯分解制苯酚丙酮反应的研究

对固体酸催化过氧化氢异丙苯分解制苯酚丙酮反应进行了研究,发现以β沸石为载体、磷钨酸为主催化剂、硫酸钛为助催化剂制备的负载型催化剂,对该反应具有较高的催化活性和选择性.同时,考察了催化剂制备条件、反应温度、原料配比等因素对催化剂活性的影响.结果表明,磷钨酸含量为25％、硫酸钛含量为5％、焙烧温度250℃、焙烧时间4 h;...     

一种制备无氯苯甲醛的纳米催化剂的合成及性能

运用共沉淀法制备了系列锌锰复合纳米催化剂,并用于气相催化加氢苯甲酸合成无氯苯甲醛。经XRD,TEM,BET,IR等表征技术表明,其主要物相为ZnMnO3、ZnO和MnO2,粒径范围在80~200 nm.实验室及单管小试结果表明,该纳米催化剂不但具有很高的催化选择性,而且降低了反应温度。当反应温度为370±10℃、酸液时空速0.1 h-1、氢气时空速650±50 h-1时,苯甲酸的转化率高达99.0%,苯甲醛的选择性为94.5%。同样条件下,取140 kg的催化剂在厦门涌泉集团做了中试,得到苯甲酸的转化率为98%,苯甲醛的选择性为83.2%。     

Treatment of chlorophenols-bearing wastewaters through hydrodechlorination using Pd/activated carbon catalysts

The catalytic hydrodechlorination of 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol in aqueous solution over Pd/activated carbon catalysts (0.5% w/w Pd) was studied in a fixed bed reactor. The reactor was fed with a 100 mg/l solution of chlorophenol and a H₂/N₂ (1:1) gas stream. The ranges studied for temperature, pressure and space-time were 25-100 °C, 1.8-6.0 bar and 14-55 kg h/mol, respectively. A commercial and some home-made catalysts were tested. The carbon supports were subjected to oxidation with nitric acid and sodium persulfate. Chlorophenols conversion was found to peak for pressure values ≈2.4 bar. In these conditions, an increase of reaction temperature increases conversion. In the runs carried out at high space-time both the reactants conversion and the selectivity towards end chain reaction products was enhanced. The oxidation of the carbon support with nitric acid prior to impregnation improves conversion. At the optimum conditions (2.4 bar, 75 °C and nitric acid oxidation of carbon support) conversion values over 95% were reached for all chlorophenols. As a result of this treatment the toxicity of the initial solutions was reduced by more than 90%.     

高酸原油直接催化裂化反应规律研究

在实验室XTL-5型提升管中试装置上考察了反应温度、剂油质量比和停留时间对苏丹高酸原油催化裂化反应的影响。实验结果表明,在反应温度460℃、停留时间1.15 s、剂油比为6左右的缓和条件下,苏丹高酸原油的重油转化率在90%以上,液收可以达到80%以上。由于原料的残炭质量分数大于8%,导致苏丹达尔原油的直接催化裂化焦炭产率较高。随反应温度的升高和停留时间的延长,转化率不断提高,但汽柴油收率不断下降。随剂油比的增大,汽油产率先升高后降低,柴油收率则不断下降。