间甲基苯腈的硝化及产物的结构表征

以浓硝酸为硝化剂硝化间甲基苯腈得到3种硝基间甲基苯腈的异构体。在n(间甲基苯腈)∶n(发烟硝酸)=1∶10,反应时间2 h,反应温度18~20℃的条件下,冰浴中将浓硝酸缓慢滴加到间甲基苯腈中,得3种硝基间甲基苯腈异构体,粗品总收率92%。经柱层析和重结晶,从粗产物中分离出3种纯异构体,分别为3-甲基-4-硝基苯腈、3-甲基-6-硝基苯腈和3-甲基-2-硝基苯腈,以间甲基苯腈计,收率分别为43%、37%和12%。应用核磁共振、红外和气质联用技术,表征了3种纯异构体的结构,对硝化反应的位置选择性进行了初步分析。     

尿素氨化制备歧化松香腈的研究

以歧化松香为原料 ,在氯化钴和硼酸催化作用下 ,用尿素氨化 ,制得了歧化松香腈 ,以歧化松香计 ,歧化松香腈的收率为 83.3%。讨论了原料比、催化剂、反应温度、反应时间等因素对反应的影响。     

ZnCl_2离子液体催化合成六氯环三磷腈

ZnCl_2与氯化吡啶构成一类具有Lewis酸性离子液体,以其为催化剂,五氯化磷与氯化铵在氯苯中合成了六氯环三磷腈。与ZnCl_2催化体系相比,不仅显著地加快了反应速率,而且明显提高了六氯环三磷腈的收率。当ZnCl_2与吡啶卤化物物质的量比为6:4、反应温度为132℃、反应时间3.1 h时,六氯环三磷腈收率为80.95%。分离后的离子液体真空提纯后,重复使用4次其催化活性基本保持不变。     

甲苯氨氧化反应制备苯腈及苯代三聚氰胺的合成

利用连续流动式固定床反应器和气相色谱仪研究甲苯氨氧化制备苯腈,苯腈和双氰胺反应得到苯代三聚氰胺。讨论了反应温度、原料配比对苯腈收率和质量的影响。结果表明,最佳反应条件为:反应温度633 K,空比30,氨比6,空速540 h~(-1),此时苯腈的收率94%。在反应时间2 h,苯腈与双氰胺摩尔比0.8,洗涤5次时,苯代三聚氰胺收率93%以上,m.p.226℃。     

1,3,5-三取代六氢均三嗪类化合物的合成

以乙腈、丙腈、丁腈和苯甲腈与三聚甲醛合成了1,3,5-三取代六氢均三嗪类化合物,采用核磁共振、红外光谱、质谱和有机元素分析等手段鉴定了其结构,通过正交试验研究了有机腈与三聚甲醛摩尔比、反应温度、反应时间和溶剂等因素对目标化合物收率的影响.结果表明,在最优条件下,乙腈、丙腈、丁腈和苯甲腈与三聚甲醛反应时,相应的1,3,5-三取代六氢均三嗪类化合物产物收率分别为95.7%、96.1%、84.2%和98.1%.     

三氟甲磺酸钐催化合成芳酰腈类化合物

[目的]研究芳酰腈化合物的合成新方法。[方法]在三氟甲磺酸钐的催化下,芳酰氯与氰化钠反应得到相应的芳酰腈类化合物。[结果]最佳条件下,芳酰腈类化合物的收率达90%左右,纯度98%以上。[结论]该路线反应条件温和,选择性高,无需使用相转移催化剂,为芳酰腈类化合物提供了一种实用的新合成方法。     

2,3,5,6-四氟对苯二甲腈的合成

2,3,5,6-四氯对苯二甲腈与氟化钾在DMSO-甲苯混合溶剂中于120～130℃反应5 h,产物2,3,5,6-四氟对苯二甲腈的收率为76.5%,含量98.5%。用简便的溶剂与水共沸去水对KF和DMSO-甲苯进行无水处理,讨论了反应温度、时间等条件对反应收率的影响。     

甲苯氨氧化反应制备苯腈及苯代三聚氰胺的合成

利用连续流动式固定床反应器和气相色谱仪研究甲苯氨氧化制备苯腈,苯腈和双氰胺反应得到苯代三聚氰胺。讨论了反应温度、原料配比对苯腈收率和质量的影响。结果表明,最佳反应条件为:反应温度633 K,空比30,氨比6,空速540 h^(-1),此时苯腈的收率94%。在反应时间2 h,苯腈与双氰胺摩尔比0.8,洗涤5次时,苯代三聚氰胺收率93%以上,m.p.226℃。     

合成2-氯丙烯腈的研究

以丙烯腈为原料,经过催化加氯、消除反应合成制得2-氯丙烯腈.主要考察了反应温度、催化剂的用量、反应时间及反应体系的pH值等对反应收率的影响.结果表明,在无溶剂条件下,加成反应温度10～15 ℃,加成催化剂L用量是丙烯腈质量的6%,通气时间3 h;不使用阻聚剂,自制消除催化剂T用量为2,3-二氯丙腈质量的8%,反应体系pH值为8时,2-氯丙烯腈的收率达到97%以上,产品纯度可达99%.     

2-羟基-3-甲基-3-丁烯腈的合成

通过甲醛与丙醛在盐酸二乙胺催化下缩合合成了 2 甲基丙烯醛 ,收率为 98%。反应操作分两阶段进行 ,第一阶段反应的pH值为 7,温度为 45℃ ;第二阶段反应在沸腾状态下进行 ,通过蒸馏得到产品。催化剂重复使用 4次对反应收率无显著影响。 2 甲基丙烯醛与氰化钠、盐酸在强烈搅拌 ,反应温度≤ 5℃下反应得 2 羟基 3 甲基 3 丁烯腈 ,收率 92 %。产品结构用1H NMR进行了确定。     

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.     

合成三羟甲基丙烷三丙烯酸酯的研究

以三羟甲基丙烷(TMP)、丙烯酸(AA)为原料,环己烷和甲苯混合物为带水剂,合成了三羟甲基丙烷三丙烯酸酯(TMPTA).考察了原料配比、阻聚剂用量、催化剂种类和夹水剂用量等因素对产物收率的影响.结果表明:n(AA):n(TMP)=4.0:1,催化剂A用量为3.0%,阻聚剂对苯二酚和对羟基苯甲醚(MEHG)用量分别为0....     

超临界汽油中煤焦油加氢裂化催化剂研究

为了提高超临界汽油中煤焦油加氢裂化轻质油的收率,研究了Co-Mo-Pd-Y沸石催化剂制备条件对轻质油收率的影响。分别考察了催化剂负载金属中Co/(Co+Mo)原子比、催化剂焙烧温度、分子筛酸处理浓度、酸处理温度及时间对煤焦油加氢裂化催化反应收率的影响。结果表明:当Co/(Co+Mo)原子比(摩尔比)为0.5,催化剂焙烧温度为550℃,分子筛酸处理浓度为2 mol/L,酸处理温度为70℃及处理时间4 h时,轻质油收率(质量分数)可达81.5%,并且对此条件下制备的催化剂通过N2吸附及XRD进行了表征。制得的催化剂在超临界溶剂中煤焦油加氢裂化反应中表现出较高的活性,煤焦油获得了高的轻质油收率。     

Conversion of heavy reformate into xylenes over mordenite-based catalysts

The conversion of heavy reformate into high-value xylenes was studied over a series of H-mordenite-based catalysts in a fluidized-bed reactor at 400 °C. The results show that methyl-ethyl-benzenes (MEBs) were more reactive than trimethylbenzenes (TMBs) over all the catalysts studied. Mordenite catalyst with higher acid site concentration (M1) favored dealkylation of MEBs while another mordenite catalyst with lower acid site concentration (M2) favored disproportionation of TMBs. Mixing M2 with ZSM-5 (M2Z1) enhanced MEBs conversion (69.2%) and xylenes yield (22.5 wt.%). The conversion of heavy reformate and toluene mixtures over M2Z1 catalyst increased xylenes yield to a maximum at 25.3 wt.% for a feed containing 70:30 heavy reformate and toluene. The results of converting mixtures of 1,2,4-TMB/toluene and heavy reformate/toluene indicate that catalyst acid site concentration plays a key role in promoting desirable transalkylation reactions needed to enhance xylenes yield. The amount of coke formed increased with the acid site concentration of catalysts and more coke laydown was observed during conversion of heavy reformate than 1,2,4-TMB.     

4,4'-二羟基二苯砜合成新工艺的研究

对苯酚磺化、脱水法合成4,4'-二羟基二苯砜（BPS）工艺进行改进。研究了使用新的催化剂（2,6-萘二磺酸）和溶剂（均三甲苯-均四甲苯混合溶剂）,提高经苯酚和浓硫酸合成BPS的收率和纯度。详细研究了合成过程中所用溶剂类型及混合溶剂比例、催化剂种类及用量对BPS收率、纯度及异构体2,4'-二羟基二苯砜变化规律的影响。较好的工艺条件为：100 g均三甲苯-均四甲苯混合溶剂（二者质量比3∶1）,5 g 2,6-萘二磺酸催化剂,98.5 g苯酚,在110 ℃将51.2 g硫酸滴加完成后,将反应液快速升温至回流温度172 ℃并保持5 h。BPS产品收率可达99.3%,纯度为96.49%。该方法收率高,催化剂便宜,易于工业化。     

沙柳酸催化水解制备乙酰丙酸及分离提纯

以沙柳为原料,硫酸为催化剂,考察了催化剂浓度、反应时间、反应温度、液固比对沙柳水解制备乙酰丙酸得率的影响,通过正交实验方法得到最佳的水解反应条件为：反应温度200 ℃,反应时间90 min,催化剂质量分数9%,液固比（mL∶g）15∶1,乙酰丙酸的最高得率为18.80%;各因素对水解反应影响的大小顺序为：反应时间＞催化剂浓度＞反应温度＞液固比。在静态条件下,用335弱碱性阴离子交换树脂对水解液进行分离提纯,在附吸温度为35 ℃、树脂投料量为15 g、盐酸洗脱剂浓度为0.5 mol/L时,乙酰丙酸的回收率为95.35%。     

新疆托里油砂的催化热解

利用固定床热解装置,考察了温度、氢气浓度、催化剂种类及催化剂与油砂的接触方式对新疆托里油砂热解特性和油砂油收率的影响及催化剂对热解反应活化能的影响. 结果表明,在N2气氛下,550℃时,油砂油收率最高,达44.52%(w);热解气氛中H2浓度增加可促进油砂油中饱和分的二次裂解,使油砂油收率减小,烃类气体产率增加,H2浓度为40%(j)时,饱和分含量降至28.96%(w),较纯N2气氛减少25.43%;以2%(w)的NiO, WO3, ZnO和纳米CuO为催化剂,油砂油产率分别增加15.77%, 16.87%, 3.79%和5.62%;金属氧化物催化剂与油砂的接触方式对油砂油收率有较明显的影响,NiO与油砂分层放置时有利于提高油砂油收率及品质,而纳米CuO和WO3更适合与油砂混合热解;ZnO, NiO和纳米CuO可有效降低油砂热解的活化能.     

Catalytic conversion of concentrated miscanthus in water for ethylene glycol production

Miscanthus, a promising energy crop, was used for ethylene glycol (EG) production through one‐pot catalytic conversion. With a binary catalyst composed of commercial tungstic acid and Raney Ni, the miscanthus with 1 % concentration was transformed into EG with a yield of 35.5%. However, the yield dropped to 13.6% as the miscanthus concentration was increased to 10 %. The underlying reason for the yield decrease was disclosed through analysis of the liquid products, investigation of pretreatments, and characterization of the catalysts. It was found that the protectors on the surface of miscanthus and the lignin component underwent decomposition under reaction conditions, resulting in the formation of some organic acids and unsaturated compounds that preferentially poisoned the Raney Ni catalyst and consequently decreased the EG yield. When the inhibitors were effectively removed by base solvent pretreatment, the EG yield was successfully improved to 39.0% even under 10% concentration of feedstock. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2254–2262, 2014     

Effect of an organic dicarboxylic acid salt on fractionated crystallization of polypropylene droplets

The effect of a particulate nucleating agent on fractionated crystallization of polypropylene (PP) was studied. A novel method utilizing breakup of PP nanolayers was used to obtain a dispersion of PP droplets in a polystyrene (PS) matrix. An assembly with hundreds of PP nanolayers alternating with thicker PS layers was fabricated by layer‐multiplying coextusion. The concentration of an organic dicarboxylic acid salt (HPN) nucleating agent in the coextruded PP nanolayers was varied up to 2 wt %. When the assembly was heated into the melt, interfacial driven breakup of the thin PP layers produced a dispersion of PP particles in a PS matrix. Analysis of optical microscope images and atomic force microscope images indicated that layer breakup produced a bimodal particle size distribution of submicron particles and large, micron‐sized particles. Almost entirely submicron particles were obtained from breakup of 12 nm PP layers. The fraction of PP as submicron particles dropped dramatically as the PP nanolayer thickness increased to 40 nm. Only large, micron‐sized particles were obtained from 200 nm PP nanolayers. The crystallization behavior of the particle dispersions was characterized by thermal analysis and wide angle X‐ray diffraction. Only part of the PP was nucleated by HPN. It was found that HPN was not effective in nucleating the population of submicron particles. The particulate HPN was too large to be accommodated in the submicron PP particles. On the other hand, the amount of nucleated crystallization qualitatively paralleled the fraction of PP in the form of large, micron‐sized particles. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

新型Cu/ZrO2环己醇脱氢催化剂的制备

以硝酸铜、氧氯化锆为原料，配制成n(Zr)∶n(Cu)＝（1～4）∶1的溶液，以w（NaOH）＝15％溶液为沉淀剂，采用共沉淀法，制备出新型Cu/ZrO₂环己醇脱氢催化剂。通过正交试验选择出较优的催化剂制备条件为：n(Zr):n(Cu)=2∶1，锆盐初始浓度0.2 mol·L^－1，焙烧时间5 h，焙烧温度400 ℃，滴定终点pH值为12。考察了催化剂预处理、反应温度等对脱氢过程产物收率和选择性的影响。在优化条件下制得的催化剂用于环己醇脱氢时，环己酮产品收率达85%，选择性近100％。