三相体系中TS-1分子筛催化环己酮氨肟化制环己酮肟(英文)

An innovative green process of producing ε-caprolactam was proposed by integrating ammoximation and Beckmann rearrangement effectively. As a first part of the new process, TS-1 molecular sieve-catalyzed synthesis of cyclohexanone oxime from cyclohexanone, ammonia and hydrogen peroxide was carried out in a batch plant. Cyclohexane was used as the solvent in the three-phase reaction system. The influences of essential process parameters on ammoximation were investigated. Under the reaction conditions as catalyst content of 2.5% (by mass); H 2 O 2 /yclohexanone molar ratio of 1.10; NH 3 /cyclohexanone molar ratio of 2.20; reaction temperature of 343 K; reaction time of 5 h, high conversion of cyclohexanone and selectivity to oxime (both>99%) were obtained. Thus, the three-phase ammoximation process showed equal catalytic activity as TS-1 but much more convenient and simpler for the separation of catalyst in comparison to the industrial two-phase system with t-butanol used as solvent.     

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.     

化学修饰Novozym-435酶催化合成维生素E琥珀酸酯的研究

Vitamin E succinate was synthesized in organic solvents using a modified Novozym-435 as catalyst.In order to improve the catalytic performance of Novozym-435,the enzyme was modified using acetic anhydride, propionic anhydride and succinic anhydride separately.We found that both the hydrolytic activity and the thermal stability of the modified Novozym-435 were enhanced compared with the unmodified enzyme.The modified Novozym-435 catalysts were used to synthesize the succinate derivative of vitamin E.Compared with the native Novozym-435,the catalytic activity of the modified novozym-435 in promoting the synthesis of vitamin E succinate was dramatically increased,with the novozym-435 modified with succinic anhydride(N435-S)as the most active catalyst.Conditions for the synthesis of vitamin E succinate were also optimized.A mixture of tert-butanol and DMSO(volume ratio of 2︰3)was the most suitable medium for the reaction,whereas the appropriate molar ratio of vitamin E to succinic anhydride and reaction temperature were 1︰5 and 40°C,respectively.Under these reaction conditions,the yield of vitamin E succinate reached 94.4%.N435-S could be reused for five batches.     

生物油中乙酸和乙醇共裂化获取汽油产物的研究简

Abstract Acetic acid was selected as the model compound representing the carboxylic acids present in bio-oil. This work focuses the co-cracking of acetic acid with ethanol for bio-gasoline production. The influences of reaction temperature and pressure on the conversion of reactants as well as the selectivity and Conaposition of the crudegasoline phase were investigated. It was found that increasing reaction temperature benefited the conversion of reactants and pressurized cracking produced a higher crude gasoline yield. At 400 ℃ and 1 MPa, the conversion of the reactants reached over 99% and the selectivity of the gasoline phase reached 42.79% （by mass）. The gasoline phase shows outstanding quality, with a hydrocarbon content of 100%.     

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.     

Ionic liquid catalyzed solvent-free synthesis of chalcone and its derivatives under mild conditions

An ionic liquid(IL) catalyzed solvent-free process was developed for the direct synthesis of chalcone and its derivatives by using substituted acetophenones and benzaldehydes via aldol reaction under mild conditions. A series of acidic and basic ILs were selected and screened. The influences of cations and reaction conditions on product yield and selectivity were systematically investigated. The [Bmim]OH was identified as the optimal IL, with the highest yield and selectivity reaching up to 96.7% and 100%, respectively. A reaction mechanism-based kinetic model was established and regressed with experimental data, revealing the b-Hydroxylketone dehydrolysis with activation barrier of 37.8 k J·mol~(-1) was observed as the ratecontrolling step.     

Chemical dehydration coupling multi-effect evaporation to treat waste sulfuric acid in titanium dioxide production process

In order to concentrate the diluted sulfuric acid from the titanium dioxide(TiO_2) production of sulphate process,a new concentration process was proposed by coupling chemical dehydration and multi-effect evaporation. The ferrous sulfate monohydrate(FeSO_4·H_2O), as the dehydrant, was added to the diluted sulfuric acid to form ferrous sulfate heptahydrate(FeSO_4·7H_2O) according to the H_2SO_4-FeSO_4-H_2O phase diagrams, which partially removes the water. This process was named as Chemical Dehydration Process. The residual water was further removed by two-effect evaporation and finally 70 wt% sulfuric acid was obtained. The FeSO_4·H_2O can be regenerated through drying and dehydration of FeSO_4·7H_2O. The results show that FeSO_4·H_2O is the most suitable dehydrant, the optimal reaction time of chemical dehydration process is 30 min, and low temperature is favorable for the dehydration reaction. 45.17% of the entire removed water can be removed by chemical dehydration from the diluted sulfuric acid. This chemical dehydration process is also energy efficient with 24.76% saving compared with the direct evaporation process. Furthermore, 51.21% of the FeSO_4 dissolved originally in the diluted sulfuric acid are precipitated out during the chemical dehydration, which greatly reduces the solid precipitation and effectively alleviates the scaling in the subsequent multi-effect evaporation process.     

Effects of Assistant Solvents and Mixing Intensity on the Bromination Process of Butyl Rubber

A slow bromination process of butyl rubber （IIR） suffers from low efficiency and low selectivity （S） of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixing inten-sity on the bromination process were systemically studied in this paper. The reaction process was found constantly accelerated with the increasing dosage and polarity of assistant solvent. Hexane with 30%（by volume） dichloro-methane was found as the suitable solvent component, where the stable conversion of 1,4-isoprene transferring to target product （xA1s） of 80.2%and the corresponding S of 91.2%were obtained in 5 min. The accelerated reaction process was demonstrated being remarkably affected by mixing intensity until the optimal stirring rate of 1100 r＆#183;min-1 in a stirred tank reactor. With better mixing condition, a further intensification of the process was achieved in a ro-tating packed bed （RPB） reactor, where xA1s of 82.6% and S of 91.9% were obtained in 2 min. The usage of the suitable solvent component and RPB has potential application in the industrial bromination process intensification.     

在离子液体中钛硅分子筛催化氧化环己烷

An efficient and environmentally friendly procedure was described for easy product isolation for the oxidation of cyclohexane with tert-butyl-hydroperoxide catalyzed by titanium silicalite 1 （TS-1） in ambient-temperature ionic liquid [emim]BF4. Good yield and higher selectivity of products were found in the ionic liquid compared with in molecular solvent. The research results showed 13.2% conversion of cyclohexane, 97.6% cyclohexanol and cyclohexanone selectivity were obtained in ionic liquid under mild conditions of 90℃.     

非均相羰基氧化一步合成碳酸二苯酯的研究(Ⅴ)筛选催化剂及优化合成条件

Pd/LaxPbyMnOz, Pd/C, Pd/molecular sieve and Pd-heteropoly acid catalysts for direct synthesis of diphenyl carbonate (DPC) by heterogeneous catalytic reaction were compared and the results of DPC synthesis indicated that the catalyst Pd/LaxPbyMnOz had higher activity. The Pd/LaxPbyMnOz catalyst and the support was characterized by XRD, SEM and TEM, the main phase was Lao.szPbo.asMnOa and the average diameter could be about 25.4nm. The optimuna conditions for synthesis of DPC with Pd/LasPbyMnOz were determined by orthogonal experiments and the experimental results showed that reaction temperature was the first factor of effect on the selectivity and yield of DPC, and the concentration of O2 in gas phase also had significant effect on selectivity of DPC. The optimum reaction conditions were catalyst/phenol mass ratio l to 50, pressure 4.5MPa, volume concentration of O2 25%, reaction temperature 60℃ and reaction time 4 h. The maximum yield and average selectivity could reach 13% and 97% respectively in the     

米格列奈钙的合成新工艺

(S)-2-苄基丁二酸脱水生成酸酐后与顺式全氢异吲哚反应生成米格列奈酸及其异构体副产物酸。将副产物酸分离出并异构化为米格列奈酸;米格列奈酸经成盐得产品米格列奈钙。考察了工艺条件对反应的影响,结果表明：以10mL甲苯为溶剂,5mL乙酸酐为脱水剂,0.03mol (S)-2-苄基丁二酸在110℃下脱水反应1h,酸酐收率可达90.49%;酸酐与顺式全氢异吲哚反应产物收率可达97.60%;用乙酸乙酯对产物米格列奈酸及其异构体副产物酸进行分离后,二者HPLC含量均高于98%;以甲苯为溶剂,回流反应3h,异构体副产物酸异构化为米格列奈酸,转化率达到57.65%;产品米格列奈钙总收率可达67.49%,HPLC含量高达99.25%。中间体和产物结构用¹H NMR进行表征确认。     

Synthesis of a novel super-microporous layered material and its catalytic application in the vapor-phase Beckmann rearrangement of cyclohexanone oxime

A novel well-ordered super-microporous layered material, silica-pillared niobic acid, was synthesized by a guest-exchange route and structurally characterized by powder X-ray diffraction (XRD), infrared absorption spectroscopy (IR), thermogravimetric and differential thermal analysis (TG/DTA), transmission electron micrographs (TEM), nitrogen adsorption method and ammonia-temperature-programmed desorption (NH₃-TPD). The obtained silica-pillared layered niobic acid had a supergallery of 1.78 nm, a large BET surface area of 250 m² g⁻¹, and a high thermal stability exceeding 973 K.The pillared layered material was also found to be an efficient solid acid catalyst for the vapor-phase Beckmann rearrangement of cyclohexanone oxime. When 1-hexanol was fed with cyclohexanone oxime, this solid catalyst exhibited a 100% conversion of the oxime with a selectivity of ε-caprolactam beyond 85% at a reaction temperature of 613 K and a WHSV of 0.17 h⁻¹ in terms of cyclohexanone oxime, and there was no significant change of the conversion and selectivity within 6 h.     

固体酸催化环己酮自缩合制备二聚酮的研究

以改性酸性氧化铝为催化剂,进行了环己酮自缩合合成环己酮二聚体的催化反应。考察了反应温度、催化剂用量和反应时间等条件对环己酮自缩合反应的影响。在反应温度150℃、催化剂用量10%（质量分数）、反应时间5 h时的优化反应条件下,环己酮的一次性转化率达到80.2%,二聚酮的选择性为99.9%。与液体催化剂相比,固体酸性氧化铝催化剂具有良好的催化活性和选择性,是一种绿色高效固体酸催化剂。     

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。     

Production of alkenyl succinic anhydrides from low‐erucic and low‐linolenic rapeseed oil methyl esters

Fatty acid methyl esters from low‐erucic and low‐linolenic rapeseed oil were used to produce alkenyl succinic anhydrides. A second‐order Doehlert uniform network design was used to investigate the influence of the reaction temperature and the molar ratio between the maleic anhydride and the main unsaturated rapeseed oil methyl esters on the yield of alkenyl succinic anhydride from methyl oleate. Further subjects of investigation were the conversion of methyl oleate, the formation of side reaction products, the Gardner color of the product and its viscosity, and finally the content of maleic anhydride remaining in the medium after the reaction. Alkenyl succinic anhydride from methyl oleate was isolated by column chromatography and analyzed by IR, ¹H‐ and ¹³C‐NMR and MS. The optimal reaction conditions for obtaining the maximum yield of alkenyl succinic anhydride from methyl oleate in the experimental domain (80%) were 210‐220 °C and a maleic anhydride/rapeseed oil methyl ester molar ratio of 1.5. However, the products synthesized in these conditions showed a high degree of viscosity (0.45 kg m^?1 s^?1), a very dark color (18 Gardner color) and a high content of undesirable side products (6%), which could hinder their industrial use. A molar ratio of less than 1.5 led to a clearer and less viscous product, although with a lower alkenyl succinic anhydride content.     

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%。     

CeO2改性Ni/γ-Al2O3催化剂上顺酐加氢制备丁二酸酐

采用等体积浸渍法制备CeO₂改性Ni/γ-Al₂O₃催化剂,通过BET、XRD、H₂-TPR和SEM等对催化剂结构及物化性能进行表征,考察Ni-CeO₂/γ-Al₂O₃催化剂对顺酐催化加氢制备丁二酸酐催化性能的影响。结果表明,引入适量CeO₂可提高催化剂活性组分Ni的分散度,增加催化剂比表面积,提高催化剂热稳定性。采用负载CeO₂质量分数5%的Ni-CeO₂/γ-Al₂O₃催化剂,在反应温度120 ℃、反应压力2.0 MPa和空速0.6 h^-1条件下,顺酐转化率为99.5%,丁二酸酐选择性为99.4%。     

环己酮自缩合固体催化剂的研究

研制了一种应用于环己酮自缩合反应的新型固体催化剂CC-1。与传统的浓硫酸催化剂相比，CC-1催化剂具有更优异的选择性，操作更简便。通过对不同用量的带水剂包括环己烷、正庚烷以及甲苯的使用效果进行考察，发现以用量为50 mL的正庚烷作带水剂的效果最理想，环己酮的转化率和二聚物的选择性分别达到87.5%和97.9%。对CC-1催化环己酮缩合反应的进程研究表明，该反应具有典型的连串反应特点。对CC-1催化剂的再生性能考察表明,该催化剂具有优良的再生性能，至少可以再生8次，维持催化剂活性在转化率85%和选择性96%左右。     

H-732阳离子交换树脂催化酯化反应

以H-732阳离子交换树脂为催化剂进行了酯化反应研究,合成了丁二酸单乙酯和乙酰水杨酸,通过单因素实验和正交实验优化了反应工艺。单因素实验结果表明：催化剂用量为丁二酸酐质量的20%、乙醇与丁二酸酐的摩尔比1.8∶1、反应时间2 h、反应温度90 ℃时,丁二酸单乙酯产率最高为68.76%;在丁二酸单乙酯的合成体系中加入分离出的副产物丁二酸二乙酯可以抑制副反应的发生,大大提高单酯的产率（90.79%）。正交实验结果表明：乙酸酐与水杨酸的摩尔比为3∶1,催化剂用量为水杨酸质量的14.50%,反应时间2 h、反应温度60 ℃时,乙酰水杨酸产率最高为77.57%;催化剂连续使用5次时,催化能力才有明显下降,对连续使用过5次的催化剂重新活化后催化能力无明显降低。     

改性果胶-Fe3O4磁性微球制备及对Pb 2+吸附性能

合成了一种琥珀酸酐改性果胶-四氧化三铁（Fe₃O₄）磁性微球吸附剂,分别采用扫描电镜（SEM）、红外光谱（FT-IR）、X射线衍射（XRD）等手段对样品进行了表征,并研究了其吸附铅离子（Pb ²⁺）的性能。研究结果表明：成功制备了琥珀酸酐改性果胶-Fe₃O₄磁性微球,改性果胶包覆四氧化三铁几乎没有改变Fe₃O₄的尖晶石结构,其表面疏松多孔;改性果胶-Fe₃O₄磁性微球对铅离子的吸附符合准二级动力学方程、Langmuir等温吸附方程,吸附过程主要为化学吸附。最佳吸附条件：吸附时间为600 min,吸附温度为40 ℃,溶液pH为5,吸附剂添加量为20 mg,溶液中Pb ²⁺质量浓度为800 mg/L。改性果胶-Fe₃O₄磁性微球吸附剂用于脱除毛蚶子、扇贝酶解液中的Pb ²⁺,Pb ²⁺去除率分别为76.47%和80.34%,效果良好。