顺丁烯二酸酐制备工艺及催化剂发展研究

综述了顺丁烯二酸酐生产的工艺路线和催化剂研究发展。重点介绍了苯固定床氧化工艺和正丁烷流化床氧化工艺路线以及正丁烷氧化流化床用催化剂及晶格氧催化剂的研究发展。通过比较不难看出,我国的顺丁烯二酸酐生产工艺尚不能与国际流行的正丁烷流化床法生产工艺接轨,相应配套的催化剂研究和后续精制工艺优化水平需要进一步提高。目前应加紧做好流化床催化剂和晶格氧技术及顺丁烯二酸酐下游产品的开发。     

甲烷部分氧化制取合成气的研究

甲烷部分氧化制合成气是高转化率、高选择性、高空速、低H2/CO、温和的放热反应,文章叙述了甲烷部分氧化制合成气反应机理:间接反应和直接反应机理;对贵金属、非贵金属催化剂,助催化剂,载体及催化剂制备方法研究进行了介绍;同时对固定床、流化床及膜反应器特点进行了讨论;另外对激光促进表面反应技术和等离子体技术也进行了简单的介绍,最后对甲烷部分氧化技术存在的问题及今后的研究重点进行了展望。     

乙酰氨基阿维菌素的合成工艺

乙酰氨基阿维菌素是一种高效广谱驱虫兽药。本研究以阿维菌素经AVMB1C5—OH保护反应、C4″—OH氧化反应的产物(4″-氧-5-O-烯丙氧甲酰基阿维菌素B1)作为起始原料,在反应器中连续进行氨化反应、还原反应、解C5的保护基反应,将所得反应液进行过滤、萃取,得到的有机液相直接进行乙酰化反应,再通过结晶、干燥后得到乙酰氨基阿维菌素成品。该路线与现有工艺比较,减少了工艺步骤,更换了氨化反应催化剂,优化了合成条件,使总收率提高4.6~6.8百分点,形成了一条适宜工业化生产的合成工艺路线。     

催化合成2,4-二氯苯氧乙酸正丁酯的研究

为探索2,4-二氯苯氧乙酸正丁酯酯化反应的最佳提取条件,以固体超强酸(SO2-4/SnO2)作为催化剂,研究了催化剂用量、反应温度及醇酸比对2,4-二氯苯氧乙酸正丁酯酯化反应的影响。结果表明:以固体超强酸(SO2-4/SnO2)作为催化剂活性最高,其酯化反应最佳合成工艺条件为A2B2C2,即催化剂用量0.6%、酯化反应温度110℃、正丁醇与2,4-二氯苯氧乙酸摩尔比2∶1,2,4-二氯苯氧乙酸的转化率达99.87%。     

雄安新区分散村镇污水处理技术探讨

本文介绍了雄安新区(协调区)分散村镇污水处理背景、国内外研究现状,通过分析生物处理(厌氧、兼氧、好氧)和生态处理(土地处理、人工湿地、稳定塘)技术及其组合工艺的优缺点,筛选出缺氧+生物接触氧化+潜流人工湿地(稳定塘)工艺、缺氧+MBBR+潜流人工湿地(稳定塘)工艺。同时提出了适合于雄安新区分散村镇污水处理的推荐污水处理技术路线,希望能为雄安新区建设提供一定的参考价值。     

毒死蜱全球市值2014年将超过8亿美元

<正>毒死蜱作为替代高毒有机磷农药的首选产品之一,在国内外的市场的需求增大。国内农药生产厂家对传统的工艺路线的改进提高,以及成功开发了先进生产工艺路线,都极大地提高了国内外市场竞争力,但毒死蜱迅速发展成为一个大吨位的农药品种,有着广阔的市场前景。     

洋茉莉醛研究综述

洋茉莉醛是重要的合成香料之一,广泛应用于各种高低档香精中,本文综述了它的性质及合成的各种路线法,重点对有代表性且有实际意义的黄樟油路线及邻苯二酚最新路线法作较详细的论述和评价,建议推广臭氧氧化法工艺及开展洋茉莉醛全合成路线的研究。     

金属氧化物/吸附树脂催化分子氧氧化巴豆醛的研究

考察了金属氧化物／吸附树脂催化剂催化分子氧氧化巴豆醛的性能与催化氧化反应条件。结果表明,催化剂有较高活性和选择性,在优化反应条件下,巴豆酸产率为８７．１％。     

增塑剂DOP生产用催化剂研究进展

对增塑剂邻苯二甲酸二辛酯(DOP)生产中所采用的各种催化剂的催化机理及对产品生产工艺、产品质量的影响进行了综述，认为非酸性催化剂在增塑剂生产中生产工艺优化，产品质量好，工艺简单，环境污染小，显示出独特的优越性。     

用含锌废渣研制微量元素化肥硫酸锌

本文介绍用含锌废渣(含锌20—30%,含铁3—12%)为原料,经粉碎、磁选,空气与高锰酸钾氧化除铁、锰,锌粉置换除重金属,蒸发结晶等工艺,制取七水硫酸锌。本法改进了传统的生产工艺,降低了生产成本,产品质量符合农用要求。实验表明,工艺路线合理可靠,方法行之有效,为综合利用含锌废渣开辟了一条途径。     

微波合成聚天冬氨酸对氨和磷污染控制的试验研究

通过改进聚天冬氨酸合成试验,解决马来酐和氨水为原料微波合成工艺中氨气散逸污染问题。采用马来酐溶液对合成过程中释放的氨气进行回收,在吸收液中天冬氨酸与所释放氨气的化学计量数为1.2,气体流量为0.6mol·L-1时,氨气回收效率可以达到100%;采用微波辐射方法以L-天冬氨酸为原料合成聚天冬氨酸,10gL-天冬氨酸,无磷催化剂,在功率900W下微波辐射4min,产率为96.3%,解决了传统方法中磷催化剂污染的问题。     

Enhanced ethylene and ethane production with free-radical cracking catalysts

A series of free-radical catalysts have been discovered that increase the yield of highly valuable olefins from the cracking of low molecular weight paraffins. For example, catalytic cracking of n-butane, isobutane, and propane over manganese or iron supported on magnesium oxide (MgO) gave product distributions different from those given by thermal (free-radical) cracking or cracking over traditional acid catalysts. With n-butane and propane feeds, the products from catalytic cracking included large amounts of ethylene and ethane; with isobutane feed, propylene was the major product. Physical characterization of the MgO-supported catalyst showed the manganese to be in a 2+ oxidation state in the reduced catalyst and a 4+ oxidation state in the fully oxidized catalyst. Manganese was also shown to be uniformly distributed in the support material with very little enrichment at the surface. Matrix isolation of the gasphase radicals from n-butane feed showed that ethyl and methyl radicals were produced over the active catalysts. In the thermal process, only methyl radicals were produced. The mechanism of the catalytic reaction appears to be selective formation of primary carbanions at the catalyst surface followed by electron transfer and release of primary hydrocarbon radicals to the gas phase.     

糠醇树脂改性对竹材物理、力学及防霉性能的影响

为研究糠醇改性竹材的可行性及催化剂的催化效果,分别以马来酸酐和自主研发的复配有机酸为催化剂,通 过真空加压浸渍工艺对竹材进行糠醇树脂改性处理,并对改性后竹材的物理、力学及防霉性能进行测试。结果表 明:1)改性后竹材的增重率分别达到31.03%和25.41%;2)除尺寸稳定性外,改性竹材的大部分性能都有明显改 善,即平衡含水率降低约49%,抗弯强度、弹性模量和顺纹抗压强度均有较大幅度提高,但抗压弹性模量变化不显 著;3)马来酸酐为催化剂的糠醇树脂改性竹材的力学性能改善程度优于复配有机酸;4)改性后竹材对霉菌的防治 效力达100%;5)糠醇改性对竹材尺寸稳定性有显著的负面影响;6)复配有机酸的催化效果可以与马来酸酐相 媲美。      

有机碱催化制备马来酸单淀粉酯的研究

[目的]以木薯淀粉为原料制备马来酸单淀粉酯。[方法]将木薯淀粉经乙醇活化之后,以马来酸酐为酯化剂,丙酮为反应溶剂,吡啶为催化剂,采用单因素试验法优化马来酸单淀粉酯的制备条件。[结果]制备马来酸单淀粉酯的最佳工艺条件：活化淀粉用量为1 g,反应温度为50℃,活化淀粉和酸酐的摩尔比为1∶3,吡啶用量为1 ml,反应时间为7 h。[结论]采用最佳的制备条件,制得取代度为0.332的马来酸单淀粉酯。     

Reaction-controlled phase-transfer catalysis for propylene epoxidation to propylene oxide

The epoxidation of olefins with H2O2 was performed with a tungsten-containing catalyst. This insoluble catalyst forms soluble active species by the action of H2O2, and when the H2O2 is used up, the catalyst precipitates for easy recycling. Thus, the advantages of both homogeneous and heterogeneous catalysts are combined in one system through reaction-controlled phase transfer of the catalyst. When coupled with the 2-ethylanthraquinone/2-ethylanthrahydroquinone redox process for H2O2 production, O2 can be used for the epoxidation of propylene to propylene oxide with 85% yield based on 2-ethylanthrahydroquinone without any co-products. This approach avoids the problematic co-products normally associated with the industrial production of propylene oxide.     

Solid-state defect mechanism in vanadyl pyrophosphate catalysts: implications for selective oxidation

High-resolution and in situ electron microscopy of vanadyl pyrophosphate catalysts reacted in alkane (n-butane) and other reducing environments have shown evidence for surface structure modifications accompanied by two sets of symmetry-related extended defects. Defect analysis reveals that the defects are formed by pure (glide) shear mechanism. The defect mechanism suggests the presence of basal (coplanar) anion vacancies, associated with Lewis acid centers, at oxygen sites linking corner-sharing phosphorus tetrahedra and vanadyl octahedra in the active plane. These in-plane defect sites may be key to the activation of the alkane, especially in the dehydrogenation.     

Surface-modified carbon nanotubes catalyze oxidative dehydrogenation of n-butane

Butenes and butadiene, which are useful intermediates for the synthesis of polymers and other compounds, are synthesized traditionally by oxidative dehydrogenation (ODH) of n-butane over complex metal oxides. Such catalysts require high O2/butane ratios to maintain the activity, which leads to unwanted product oxidation. We show that carbon nanotubes with modified surface functionality efficiently catalyze the oxidative dehydrogenation of n-butane to butenes, especially butadiene. For low O2/butane ratios, a high selectivity to alkenes was achieved for periods as long as 100 hours. This process is mildly catalyzed by ketonic CO groups and occurs via a combination of parallel and sequential oxidation steps. A small amount of phosphorus greatly improved the selectivity by suppressing the combustion of hydrocarbons.     

绿色阻垢剂聚环氧琥珀酸的合成试验研究

以马来酸酐为主要原料,氢氧化钙为引发剂,合成了无磷、非氮和可生物降解的绿色阻垢剂聚环氧琥珀酸(PESA),得出了最佳合成工艺条件,并对合成产物进行了红外光谱表征。     

马来酸酐合成富马酸二甲酯新工艺及应用

提出了一种合成富马酸二甲酯的新方法。以马来酸酐为原料 ,对甲苯磺酸作催化剂 ,二氯甲烷作溶剂与甲醇作用进行酯化反应 ,所得产物再在氯存在下经光照可异构成富马酸二甲酯。研究了溶剂种类、甲醇用量、反应时间对DMF产率的影响 ,确定了最佳工艺条件 :马来酸酐 9 8g、甲醇 35ml、二氯甲烷 2 5ml、对甲苯磺酸 0 2 5g ,在10 6℃搅拌回流反应 3小时。在此条件下DMF产率可达 90 % ,并得到了一些物性和毒性数据 ,简述了其应用领域