Ti-SBA-15介孔分子筛催化制备环氧橡胶籽油的研究

以橡胶籽油(RSO)为原料,采用非均相介孔分子筛催化剂Ti-SBA-15催化制备环氧橡胶籽油(ERSO),探讨了催化剂用量、氧化剂叔丁基过氧化氢(TBHP)用量、反应时间、反应温度等因素对环氧化反应的影响。结果表明,Ti-SBA-15介孔分子筛催化剂催化制备ERSO的最佳工艺条件为:催化剂Ti-SBA-15用量0.062%(摩尔分数,以RSO物质的量计),TBHP与RSO物质的量比为1.3:1,反应时间6 h,反应温度70℃,此条件下制备的ERSO环氧值为68.9 mmol/g,产物转化率为82.22%,双键转化率为69.93%。通过FT-IR对比分析,进一步证实了环氧基团的生成。     

Rapid Screening of an Acid‐Catalyzed Triglyceride Transesterification in a Mesoscale Reactor

A mesoscale oscillatory baffled reactor (meso‐OBR) served as a continuous screening platform to rapidly investigate the operating conditions for acid‐catalyzed production of fatty acid methyl ester (FAME) from triglyceride feedstock. The acid catalyst was 4‐dodecylbenzenesulfonic acid (DBSA) and the triglyceride feedstock was rapeseed oil (RSO). The parameter space was explored by means of a design of experiments (DoE) methodology. The variables screened were methanol‐to‐RSO molar ratio, catalyst‐to‐oil molar ratio, and residence time. Over 98 % conversion of RSO to FAME could be achieved under optimized conditions.     

CS-2型催化剂载体的脱醇试验及对聚合物细粉产生的影响

通过对CS-2催化剂的载体在不同条件下的脱醇实验,得到不同乙醇/氯化镁摩尔比(简称醇镁比)的载体,不同载体合成催化剂后经高压聚合得到聚合产物.结果表明,改变脱醇条件可得到不同醇镁比的载体,而不同醇镁比的载体合成的催化剂其聚合产物细粉生成量有较大变化.     

阳离子交换树脂作催化剂合成乙酸乙酯的研究

以DOWEX MARATHONC型强酸性阳离子树脂为催化剂,在常压液相下用乙酸和乙醇合成乙酸乙酯。考察了反应温度、反应时间、催化剂用量和反应物初始摩尔比等参数对反应体系的乙酸乙酯收率影响。通过正交实验得到优化反应条件:反应时间为55 min,反应温度为70℃,催化剂用量为110 g/L,醇与酸摩尔比为1.5∶1,乙酸乙酯收率可达62%。     

硅酸钠为硅源的介孔分子筛SBA-15-SO3H的研究

在强酸性和水热条件下以硅酸钠（Na₂SiO₃·9H₂O）为硅源合成表面含磺酸基的介孔分子筛催化剂SBA-15-SO₃H。XRD结果表明，该分子筛具有规则的六方立柱形介孔结构。SBA-15-SO3H用于叔丁醇和乙醇合成乙基叔丁基醚（ETBE）的醚化反应研究，分别考察了反应温度、原料配比和反应时间等因素对醚化反应的影响。最佳操作条件为：温度120 ℃，n(乙醇)∶n(叔丁醇)=2∶1，反应时间5 h，m(催化剂) ∶m(原料)=1∶10。在此条件下，叔丁醇的转化率为62.83%。     

硅胶负载四氯化锡催化合成N,N-二乙氨基乙醇己酸酯

以硅胶为载体,用浸渍法制备了不同负载量的SnCl4催化剂,用于催化合成DA-6(N,N-二乙氨基乙醇己酸酯),通过BET法对SnCl4/SiO2催化剂的表面结构进行了分析。考察了SnCl4负载量、催化剂用量、原料摩尔配比、反应温度对N,N-二乙氨基乙醇己酸酯收率的影响,实验结果表明:当n(N,N-二乙氨基乙醇):n(己酸)=1:1.2、54.1%SnCl4/SiO2催化剂用量为反应原料的2(m/m)%、溶剂为甲苯、反应时间6h时,DA-6收率达94.4%。     

Oxidative reforming of biomass derived ethanol for hydrogen production in fuel cell applications

Oxidative reforming of biomass derived ethanol over an inexpensive Ni–Cu/SiO₂ catalyst has been carried out with respect to solid polymer fuel cell (SPFC) applications. Two types of runs were performed, either under diluted conditions (with helium as diluent) or under conditions corresponding to an on-board reformer. Selectivities of ethanol reforming have been analyzed as a function of operating parameters: reaction temperature, H₂O/EtOH molar ratio and O₂/EtOH molar ratio of the feed to the reformer. The hydrogen content and the CO₂/CO_x molar ratio in the outlet gases were used as parameters to optimize the operating conditions in the reforming reactor. The tests carried out at on-board reformer conditions evidenced that an H₂O/EtOH molar ratio=1.6 and an O₂/EtOH molar ratio=0.68 at 973 K allow a hydrogen rich mixture (33%) that can be considered of high interest for SPFC. Furthermore, the use of oxygen decreases the production of methane and coke which increases in turn the lifetime of the catalyst. The stability of this catalyst has been fully demonstrated by long time runs.     

离子液体催化反应精馏合成乙酸乙酯工艺模拟

为研究离子液体在反应精馏中的作用,采用离子液体1-丁基-3-甲基咪唑硫酸氢盐（[BMIM]HSO₄）作为催化剂,对乙酸和乙醇合成乙酸乙酯的反应精馏流程进行了计算模拟。在确定了参数的酯化反应动力学的基础上,用Aspen Plus软件建立了反应精馏流程,研究了催化剂用量、精馏段理论板数、反应段理论板数、乙醇进料位置、进料摩尔比、持液量及回流比等参数对反应精馏过程的影响。研究结果表明,塔顶乙酸乙酯的质量分数随催化剂用量、精馏段理论板数、反应段理论板数和持液量增大而增大,工艺流程存在最佳回流比以及最佳进料酸醇摩尔比。得到的优化条件如下：离子液体与乙酸摩尔比为1：2.5,进料酸醇摩尔比为4：1,理论塔板数为21块,乙酸和催化剂在第7块理论塔板进料,乙醇在第19块理论塔板进料,塔板持液量0.1L,回流比为4,塔顶乙酸乙酯的质量分数可以达到98.73%。     

CO‐Free Hydrogen Production by Ethanol Steam Reforming in a Pd–Ag Membrane Reactor

In this work, the ethanol steam reforming (ESR) reaction has been studied by using a dense Pd–Ag membrane reactor (MR) by varying the water/ethanol molar ratio between 3:1 and 9:1 in a temperature range of 300–400 °C and at 1.3 bar as reaction pressure. The MR was packed with a commercial Ru‐based catalyst and a constant sweep gas flow rate in counter current mode was used. The influence of the temperature and the feed molar ratio on different parameters such as the ethanol conversion, the hydrogen production, the hydrogen yield and the CO‐free hydrogen recovery has been evaluated.     

Na/SiO2新型固体碱催化制备生物柴油的研究

以NaOH、正硅酸乙酯和乙醇为原料,经溶胶-凝胶法制备新型固体碱催化剂（Na/SiO₂）,用于催化大豆油与甲醇的酯交换反应制备生物柴油,研究催化剂焙烧温度、n(NaOH)∶n(SiO₂)、n(甲醇)∶n(大豆油)、催化剂用量和反应时间对产率的影响以及催化剂的稳定性。结果表明,固体碱催化剂Na/SiO₂在大豆油与甲醇的酯交换反应中具有较高的催化活性,在催化剂焙烧温度600 ℃、n(NaOH)∶n(SiO₂)=2∶1、n(甲醇)∶n(大豆油)=15∶1、催化剂用量为大豆油质量的7%和反应时间3 h的条件下,脂肪酸甲酯产率可达97.42%,催化剂在稳定性试验中呈现出优良的稳定性。     

Biodiesel from canola oil using a 1 : 1 molar mixture of methanol and ethanol

Canola oil was transesterified using a 1 : 1 molar mixture of methanol and ethanol (M/E) with potassium hydroxide (KOH) catalyst. The effects of catalyst concentration (0.5–1.5 wt‐%), molar ratio of M/E to canola oil (3 : 1 to 20 : 1) and reaction temperature (25–75 °C) on the percentage yield measured after 2.5 and 5.0 min were optimized using a central composite design. A maximum percentage yield of 98% was obtained for a catalyst concentration of 1.1 wt‐% and an M/E to canola oil molar ratio of 20 : 1 at 25 °C at 2.5 min, whereas a maximum percentage yield of 99% was obtained for a catalyst concentration of 1.15 wt‐% and all molar ratios of reactants at 25 °C at 5 min. Statistical analysis demonstrated that increasing catalyst concentration and molar ratio of reactants resulted in curvilinear and linear trends in percentage yield, both at 2.5 and 5 min. However, reaction temperature, which affected the percentage yield at 2.5 min linearly, was insignificant at 5 min. The resultant mixed methyl/ethyl canola esters exhibited enhanced low‐temperature performance and lubricity properties in comparison to neat canola oil methyl esters and also satisfied ASTM D6751 and EN 14214 standards with respect to oxidation stability, kinematic viscosity, and acid value.     

Synthesis and characterization of rubber‐seed‐oil‐based polyurethanes

Novel biobased polyurethanes were synthesized from rubber seed oil (RSO), a renewable resource. The RSO monoglyceride, together with xylene and hexamethylene diisocyanate (HMDI), was employed to synthesize the desired urethane‐based prepolymer with isocyanate (NCO)‐terminated end groups followed by curing. The degrees of crosslinking of the polyurethane after curing were assessed with their swelling behavior. The properties of the resulting polyurethanes were found to be dependent on the type of diisocyanate and their molar ratios to the RSO monoglyceride. The network structures, which were assessed through swelling studies, showed that networks based on HMDI with an NCO/OH ratio of 1.50 were better crosslinked than with those toluene diisocyanate. The thermal properties of the samples analyzed by thermogravimetric analysis showed two and three decomposition stages in aliphatic‐ and aromatic‐based RSO polyurethanes, respectively. The highest stability with initial decomposition temperature (253°C) and percentage residual at 500°C (11.4%) was achieved with an aliphatic‐based RSO polyurethane. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

SO4^2-/TiO2-La2O3固体超强酸催化合成乳酸乙酯

采用TiCl4和La（NO3）3·6H2O共沉淀法制备固体超强酸SO4^2-/TiO2-La2O3催化剂。制备条件为nTi/nLa比为8：1,-15℃陈化24h,120℃干燥12h,浸渍液硫酸浓度为0．5mol·L^-1,浸渍4h,120℃干燥1h,400℃焙烧4h的催化剂对乳酸与乙醇的酯化反应有较高的活性。将此催化剂用于乳酸和乙醇合成乳酸乙酯的酯化反应,考察了催化剂用量、乙醇和乳酸的物质的量的比、反应时间、带水剂环己烷的用量对酯化反应的影响。实验结果表明,醇酸物质的量的为2．0：1,催化剂用量为所用乳酸质量的1．4％,环己烷为乙醇体积的78％,反应时间4h条件下酯化产率达82％。催化剂易回收,使用寿命长的优点。     

响应面法优化一水硫酸氢钠流化催化精馏生产乙酸乙酯工艺条件

以新型的一水硫酸氢钠为催化剂,采用粉末状催化剂混合乙酸一起进料的加入方式,即流化催化精馏工艺,并利用响应面法优化乙酸乙酯催化精馏过程条件.首先,通过单因素灵敏度分析法对乙酸进料量、酸醇进料摩尔比、回流比、催化剂用量、釜底加热功率5个因素进行实验考察,确定了乙酸进料量、酸醇摩尔进料比、回流比3个关键因素的优化值及取值范围.根据单因素实验结果与精馏塔设备要求,塔釜加热功率和催化剂用量分别设定为68 W和2.0%(质量分数)乙酸,采用中心组合设计原则对乙酸进料量、酸醇进料摩尔比和回流比3个关键因素进行实验设计.以乙醇转化率为响应值,基于响应实验结果,利用响应面法对实验结果进行了方程回归,得到3个关键因素与响应值的二次关联模型.通过方差分析和平行实验,证明该模型准确可用.优化后的乙酸乙酯流态化催化精馏工艺条件为乙酸进料量3.2 mol·h^-1,酸醇进料摩尔比为3.1,回流比为3.3,在此优化条件下进行实验,乙醇转化率为88.67%,比基于单因素灵敏度分析法得到的优化工艺条件下乙醇转化率高1.0%.     

乙醇与餐饮废油制备生物柴油的工艺研究

以餐饮废油和乙醇为原料,以氢氧化钾为催化剂,采用酯交换法制备生物柴油。考查了醇油摩尔比、催化剂用量、反应时间和温度对原料转化率的影响。正交试验结果表明,餐饮废油与乙醇酯交换反应的最佳反应条件为：醇油摩尔比12∶1,催化剂用量1.25%,反应温度78℃,反应时间1.5h。在此反应条件下,餐饮废油转化率达65.12%;在此基础上引入四氢呋喃作助溶剂,转化率可提高至86%~90%。     

含氮杂环羧酸乙酯的微波合成

以异烟酸(烟酸)和无水乙醇为原料,浓硫酸为催化剂,在微波辐射下合成异烟酸(烟酸)乙酯,其结构通过红外光谱、质谱进行了确证。同时研究了醇酸物质的量比、催化剂用量及反应时间对酯化产率的影响,结果表明,醇酸物质的量比为8∶1,催化剂用量为8.0mL(0.15mol),反应时间为40min时,微波辐射功率为300 W的优化条件下,酯化产率最高,相应的产率为89.2%和95.0%。     

NaY分子筛负载有机膦酸催化合成硬脂酸乙酯

以硬脂酸和无水乙醇为原料,NaY分子筛负载有机膦酸NaY/OPA为催化剂,催化合成硬脂酸乙酯。考察了催化剂用量、醇酸物质的量比、反应时间和反应温度等条件对酯化反应的影响。实验结果发现在2 g催化剂、醇酸物质的量比为4∶1、100℃,回流反应4 h条件下反应转化率可达到70.1%。     

碘催化合成4-硝基查尔酮

以碘为催化剂,苯甲醛与4-硝基苯乙酮经羟醛缩合反应合成了4-硝基查尔酮。考察了醛酮物质的量比、催化剂用量、反应时间和不同溶剂对4-硝基查尔酮收率的影响。结果表明,以乙醇为溶剂,在回流条件下,当4-硝基苯乙酮的用量为10 mmol,苯甲醛的用量为12 mmol,即酮醛物质的量比为1∶1.2,催化剂用量为6 mmol,反应3.0 h时,查尔酮收率可达到75.51%,且具有很高的纯度。     

室温离子液体催化合成肉桂酸乙酯

以室温离子液体为催化剂,以肉桂酸和乙醇为原料合成了肉桂酸乙酯,采用红外光谱和气相色谱—质谱对产品结构进行表征,考察了催化剂种类、酸醇物质的量比、反应时间、室温离子液体用量等对反应的影响,确定最佳反应条件为:肉桂酸用量1.48 g(0.01 mol)、酸醇物质的量比1 ∶ 7、催化剂[Bmim]BF4用量2 mL、加热回...     

Optimization of Cottonseed Oil Ethanolysis to Produce Biodiesel High in Gossypol Content

Transesterification of cottonseed oil was carried out using ethanol and potassium hydroxide (KOH). A central composite design with six center and six axial points was used to study the effect of catalyst concentration, molar ratio of ethanol to cottonseed oil and reaction temperature for percentage yield (% yield) and percentage initial absorbance (%A _385nm) of the biodiesel. Catalyst concentration and molar ratio of ethanol to cottonseed oil were the most significant variables affecting percentage conversion and %A _385nm. Maximum predicted % yield of 98% was obtained at a catalyst concentration of 1.07% (wt/wt) and ethanol to cottonseed oil molar ratio of 20:1 at reaction temperature of 25 °C. Maximum predicted %A _385nm of more than 80% was obtained at 0.5% (wt/wt) catalyst concentration and molar ratio of 3:1 at 25 °C. The response surfaces that described % yield and %A _385nm were inversely related. Gossypol concentration (% wt), oxidative stability and %A _385nm of biodiesel were found to be highly correlated with each other. Hence, color %A _385nm is a measure of the amount of pigments present in biodiesel fuels that have not yet been subjected to autoxidation. High gossypol concentration also corresponds to a fuel with high oxidative stability. The fatty acid ethyl esters (FAEE) produced from cottonseed oil had superior oxidative stability to fatty acid methyl esters (FAME) produced from cottonseed oil.