维生素C催化合成乳酸正丁酯的研究

以乳酸和正丁醇为原料,用维生素C作为催化剂合成乳酸正丁酯,然后进行蒸馏并收集160～190℃的馏分为产品.讨论了催化剂种类、m（催化剂）、反应时间及V（醇）对酯化反应的影响,采用红外光谱对产物进行了表征,测定了产品的折光率.结果表明：用0.5g维生素C作为催化剂,0.1 mol乳酸和0.1 mol正丁醇,回流分水2h,酯产率可达到58.2％.     

固相反应合成多元微肥缓溶磷酸锌铵及其表征

以聚乙二醇-400（PEG-400）为模板,以硫酸锌和磷酸铵为原料经低热固相反应合成了缓溶磷酸锌铵多元微肥,用热重/差热（TG/DTA）、X射线衍射（XRD）和红外光谱对其主要产物进行分析表征.结果表明该主要产物为微溶的磷酸锌铵.该合成方法除了得到微溶的磷酸锌铵外,还得到可溶的硫酸铵或者硫酸氢铵,这些产物均是肥料.显然,用该合成法合成磷酸锌铵微肥时,无需分离,其产物混合物就可以作为肥料用.该合成法不仅合成的工艺甚为简洁,而且生产过程没有废水、废渣的产生,无论是从工艺上,还是环保上均比液相法具有优势,是一种颇具工业应用前景的合成法.     

聚DL-乳酸的合成与降解性能研究

以辛酸亚锡为催化剂,采用丙交酯的开环聚合法合成了聚DL-乳酸（PDLLA）,并采用正交试验法分析了反应温度、聚合时间和催化剂用量等因素对聚合产物相对分子质量的影响。探讨了聚DL-乳酸在20～120min、180～210℃及不同环境中的热降解性能,研究了聚合物存体外模拟的生物环境中的降解特性。结果表明,当聚合温度为165℃,聚合时间为46h,催化剂用量为0．03％时聚乳酸的相对分子质量可达到21．4×10^4。在一定温度下,聚DL-乳酸的相对分子质量随热降解时间的延长而下降;聚乳酸在空气中的热降解速率比在真空中的热降解速率快。     

长链二元酸和二元醇合成聚酯的研究

以长链二元酸和二无醇为反应单体,采用熔融缩聚的方法合成了聚酯,对合成产物进行了红外吸收光谱（FTIR）、核磁共振氢谱（＇H NMR）和凝胶色谱（GPC）等表征。研究了醇酸比、反应单体、催化剂种类、催化剂用量、抽真空时间等因素对合成产物结构的影响。     

聚异丁烯磷酸酯的合成及性能研究

以高活性聚异丁烯（PIB）和苯酚为原料（C6H5OH）,三氟化硼乙醚为催化剂合成了聚异丁烯苯酚,然后加入P2O5对其进行酯化反应合成聚异丁烯磷酸酯。通过红外光谱（FT-IR）分别对合成的聚异丁烯苯酚和聚异丁烯磷酸酯进行了分析,结果表明产物为预期产物。通过差示扫描热分析（DSC）,表明聚异丁烯苯酚与高活性聚异丁烯相比具有较高的热稳定性。通过产物与大庆原油进行降凝效果的测定,证实聚异丁烯磷酸酯在大庆原油中的加入量为0.6%时降凝效果最好,降幅为9℃。     

氨基磺酸催化合成乳酸正丁酯

以氨基磺酸为催化剂,实现了乳酸与正丁醇反应合成乳酸正丁酯。最佳合成条件：以０－０８５ ｍｏｌ 乳酸为准,ｎ（ 乳酸）∶ｎ（丁醇）＝ １∶４,催化剂用量为１ ｇ,反应时间为１２０～１５０ ｍｉｎ,产率达８４％ 。该催化剂具有易回收,可循环使用,不污染环境等优点。     

新型超支化镍系催化剂的合成及对乙烯齐聚的催化性能

以直链十二胺为核的0.5代超支化大分子（R₁₂-0.5G）和丁二胺为原料,合成出一种新型的1.0代超支化大分子（R₁₂-1.0G）。然后以R₁₂-1.0G、水杨醛和NiCl₂·6H₂O为原料,依次经过希夫碱反应和络合反应合成了一种新型的超支化水杨醛亚胺镍系催化剂。FTIR、¹H NMR、UV和MS证实合成产物的结构与理论结构相符。在合成的基础上,并对该催化剂催化乙烯齐聚的性能进行了研究。考察了溶剂种类、反应温度、反应压力、Al/Ni比等条件对该催化剂催化乙烯齐聚性能的影响。结果表明,该催化剂具有良好催化乙烯齐聚的性能,当以甲苯为溶剂,在甲基铝氧烷（MAO）活化下,随着反应压力和Al/Ni比增加,催化活性增加;而催化活性随着反应温度的增加先升高后下降;在反应温度为25℃、反应压力为0.5MPa、Al/Ni比为1500时,该催化剂的活性可达5.03×10⁵g/（molNi·h）,聚合产物主要是C₆以下的低碳烯烃,含量高达89%以上。相同条件下,其催化乙烯齐聚的活性低于与其具有类似结构的“扫帚型”镍系催化剂。     

N,N-二乙基苯胺作为VE合成催化剂的研究

在环氧丙烯酸酯（VE）的合成过程中采用N，N－二乙基苯胺（DEAn)作为催化剂，成功地合成了预期产物VE树脂，合成产物色泽浅，粘度低，凝胶时间长。利和化学滴定、红外光谱（FTIR）等分析方法对VE的合成过程进行了跟踪、表征，讨论了DEAn用量对VE树脂及其固化产物性能的影响。     

W2C/AC催化快速热解松木磨木木质素

以活性炭（AC）为载体制备了不同钨负载量的W₂C/AC催化剂,将其和松木磨木木质素（MWL）机械混合后进行Py-GC/MS（快速热解-气相色谱/质谱联用）实验,考察了钨负载量、催化剂/MWL比例对产物分布的影响,并通过外标法对主要产物（芳烃类和酚类）的真实产率进行了定量分析。结果表明,W₂C/AC催化剂可有效促进木质素的热解解聚生成单酚类产物,并对酚类产物具有脱羰基、脱甲氧基、脱羟基以及加氢的效果,从而促进稳定的酚类产物（不含羰基、甲氧基和不饱和碳碳双键）和芳烃类产物的生成。在4种W₂C/AC催化剂中,10%-W₂C/AC的催化效果最佳,在催化剂/MWL比例为5时热解产物总产率达到最大值,此时芳烃类和酚类产物的总产率由无催化剂时的21.2 mg·g^-1和151.0 mg·g^-1增加至102.1 mg·g^-1和191.1 mg·g^-1。     

PET／60PABA 热致型液晶共聚酯的合成与表征

将对羟基苯甲酸（PHB）的乙酰化产物对乙酰氧基苯甲酸（PABA）引入聚酯（PET）分子主链结构中,成功制备出共聚酯 PET /60PABA,研究了聚合温度和催化剂浓度对共聚酯合成的影响。通过差示扫描量热（DSC）、X 射线衍射（XRD）、超导核磁共振（NMR）、凝胶渗透色谱（GPC）、偏光显微镜（POM）和毛细管流变仪等手段对共聚酯的分子结构与液晶形态进行表征,结果表明,共聚酯 PET /60PABA 几乎为完全无规共聚,熔融状态下具有向列型热致液晶聚合物的典型特征。     

多环硼酸化合物的脱硼酸方法与产物结构表征

以多环硼酸化合物异构体为原料,在催化剂钯碳、相转移催化剂四丁基溴化胺的作用下,于碱性条件下,60～68℃反应6～8h,得到多环化合物,收率45%～60%,并用GC-MS、IR、1HNMR、13CNMR确定了其结构。此项脱硼酸技术起到了回收有用原材料、降低多环硼酸的生产成本、减少硼酸生产中的废物排放量的作用。     

固体超强酸在酯化反应中的应用

以Ti(OC4H9)4为原料,采用溶胶-凝胶法制备固体超强酸SO42-/WO3-TiO2,以SO42-/WO3-TiO2为催化剂,通过丁酸与异戊醇反应合成丁酸异戊酯。讨论了影响酯化率的主要因素,实验结果表明,当WO3在催化剂中的质量分数为3.0%,催化剂用量为0.6 g,醇酸摩尔比为1.5∶1,反应温度为125℃,反应时间为4.0 h时,平行实验的平均酯化率可达95.1%。该工艺具有催化剂价廉易得,催化效果好,用量少,操作简单,三废少,收率高等优点。     

Long term activity of modified ZnO nanoparticles for transesterification

Biodiesel can be produced by the transesterification of natural oils with methanol using modified ZnO nanoparticles as catalyst. Crude algae oil, corn oil from DDGs, crude palm oil, crude soybean oil, crude coconut oil, waste cooking oil, food-grade soybean oil and food-grade soybean oil with 3% water and 5% FFA addition were converted into FAME within 3 h using this new catalyst. The ZnO nanoparticles were reused 17 times without any activity loss in a batch stirred reactor and the average yield of FAME was around 93.7%. ZnO nanoparticles were used continuously for 70 days in a fix bed continuous reactor and the average yield of FAME was around 92.3%. XRD, ICP, TEM and HRTEM were used to characterize the long term used catalyst structure. Results show that this catalyst is a mixture of wurtzite ZnO nanoparticles and some amorphous materials and that the used catalysts have similar crystal structure to fresh catalyst. ICP results show that this catalyst does not dissolve in biodiesel, methanol, oil and glycerine-methanol solutions. It has a stable crystal structure under the reaction conditions. The high catalytic activity, long catalyst life and low leaching properties demonstrate these modified ZnO nanoparticles have potential in a commercial biodiesel production process.     

Preparation of Cu/ZnO catalyst using a polyol method for alcohol-assisted low temperature methanol synthesis from syngas

A polyol method was used to prepare Cu/ZnO catalysts for alcohol-assisted low temperature methanol synthesis from syngas. Unlike conventional low temperature methanol synthesis, ethanol was employed both as a solvent and a reaction intermediate. Catalyst characterization revealed that Cu/ZnO catalysts were successfully and efficiently prepared using the polyol method. Various preparation conditions such as PVP concentration and identity of ZnO precursor strongly influenced the catalytic activity of Cu/ZnO catalysts. Copper dispersion and catalyst morphology played key roles in determining the catalytic performance of the Cu/ZnO catalyst in alcohol-assisted low temperature methanol synthesis. A high copper dispersion and platelike Cu/ZnO structure led to high catalytic activity. Among the catalysts tested, 5_Cu/ZnO_Zn(Ac)₂ had the best catalytic performance due to its high copper dispersion.     

Preparation and evaluation of alpha-cellulose sulfate based new heterogeneous catalyst for production of biodiesel

Alpha-cellulose obtained from wood sawdust wastes in 29.0% yield was reacted with sulfuric acid to produce alpha-cellulose sulfate materials. These catalyst materials were characterized by Fourier transform infrared and specular reflectance-UV spectroscopy, scanning electron microscopy, and laser scattering particle size distribution. The concentration of sulfate groups on the cellulosic matrix was determined by turbidimetry. The obtained alpha-cellulose sulfates can be used as efficient heterogeneous catalysts for biodiesel production from palm oil when evaluated with methylation of palmitic acid and oleic acid as the model reaction. The density of sulfate functional groups on the alpha-cellulose sulfate materials was 2.18–16.74% wt/wt as determined by turbidimetry. Standardization of deployed alpha-cellulose sulfate catalysts was achieved using different ratios of alpha-cellulose and sulfate (1:0.5, 1:1, 1:2, and 1:4 m/v). Additionally, the Bronsted acid sites on the alpha-cellulose sulfate catalyst play a pivotal role in the catalytic process.     

合成丙交酯工艺的改进

采用氧化锌(ZnO)、氯化亚锡(SnCl2)、硫酸亚锡(SnSO4)、辛酸亚锡〔Sn(Oct)2〕以及它们的混合物催化合成丙交酯。实验结果表明,催化剂的种类和用量对丙交酯的收率有显著的影响。以ZnO/Sn(Oct)2为催化剂,用量为反应物总质量的2 0%时催化效果较好,能使丙交酯的收率高达45 2%。同时在N2流速为2L/min、压力为400Pa下采用减压气流法用于丙交酯的蒸出,收率比传统的减压法增加了8 1%。此外,还设计了一个在合成中能够有效分离丙交酯和乳酸的接收器用于接收丙交酯。     

Combined experimental and kinetic modeling studies for the conversion of gasoline range hydrocarbons from methanol over modified HZSM-5 catalyst

The reaction was carried out in fixed bed reactor. The effect of process variables on the activity of oxalic acid treated 0.5 wt% ZnO/7 wt% CuO/HZSM5 catalyst for the conversion of methanol to gasoline range hydrocarbons was studied. The catalyst was prepared by incipient wetness impregnation method. After impregnation the catalyst was treated with oxalic acid. The validity of kinetic model proposed for the methanol to gasoline range hydrocarbon process at zero time on stream was studied, from the experimental results obtained in a wide range of operating conditions. The kinetic parameters for various models were calculated by solving the equation of mass conservation in the reactor for the lumps of the kinetic models. The kinetic model fitted well for simulating the operation in the fixed bed reactor in the range of 635 to 673 K, with regression coefficient (R²) higher than 0.96.     

Vapour phase hydrogenolysis of biomass‐derived diethyl succinate to tetrahydrofuran over CuO?ZnO/solid acid bifunctional catalysts

BACKGROUND: Catalytic upgrading of fermentation‐derived succinic acid or its derivates (succinic acid esters and succinic anhydride) to value added chemicals has received great attention recently. The aim of this work is to provide a process for the production of tetrahydrofuran from succinic acid esters. RESULTS: The hydrogenolysis of biomass‐derived diethyl succinate was investigated over CuO? ZnO and CuO? ZnO/solid acid (HY, HZSM‐5, SAPO‐11 and Al₂O₃) catalysts in a fixed‐bed reactor. Over CuO? ZnO, gamma‐butyrolactone and 1,4‐butanediol can be selectively produced under appropriate reaction conditions, while the selectivity of tetrahydrofuran is relatively low due to the weak acidity of CuO? ZnO. Over CuO? ZnO/HZSM, both the formed 1,4‐butanediol and ethanol can be further converted to tetrahydrofuran and diethyl ether, while tetrahydrofuran is selectively produced over CuO? ZnO/HY. CuO? ZnO/Al₂O₃ and CuO? ZnO/SAPO exhibit slight improvements in terms of selectivity to tetrahydrofuran when compared with CuO? ZnO. CONCLUSION: CuO? ZnO/HY is an appropriate catalyst to produce tetrahydrofuran from biomass‐derived diethyl succinate with high activity, selectivity and stability. Furthermore, Brønsted acid sites with appropriate acid strength are responsible for the selective formation of tetrahydrofuran under the applied reaction conditions. Copyright © 2010 Society of Chemical Industry     

Flame‐retardant finishing in cotton fabrics using zinc oxide co‐catalyst

In this article, N‐Methylol dimethylphosphonopropionamide (FR) in combination with a melamine resin (CL), phosphoric acid (PA) catalyst and zinc oxide (ZnO) or nano‐ZnO co‐catalyst were used (FR‐CL‐PA‐ZnO or nano‐ZnO system) to impart flame‐retardant property on cotton fabrics. FR‐CL or FR‐CL‐PA‐treated cotton specimen showed roughened and wrinkled fabric surface morphology, which was caused by the attack of the FR with slightly acidity. In addition, FTIR analysis showed some new characteristic peaks, carbonyl, CH₂ rocking and CH₃ asymmetric and CH₂ symmetric stretching bands, in the chemical structure of treated cotton specimens. Apart from these, the flame ignited on the flame‐retardant‐treated fabrics (without subjected to any post‐wet treatment) extinguished right after the removal of ignition source. However, FR‐CL treated specimens were no longer flame‐resistant when the specimens subjected to neutralization and/or home laundering, while FR‐CL‐PA treated specimens showed opposite results. By using 0.2% and 0.4% of ZnO or nano‐ZnO as co‐catalyst, the flame spread rate of neutralized and/or laundered test specimens decreased, even the specimens were undergone 10 home laundering cycles. Moreover, flame‐retardant‐treated cotton specimens had low breaking load and tearing strength resulting from side effects of the crosslinking agent used, while addition of ZnO or nano‐ZnO co‐catalyst could compensates for the reduction. Furthermore, the free formaldehyde content was dropped when ZnO and nano‐ZnO co‐catalyst was added in the treatment. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

从废钒催化剂中回收钒的理论与实践

介绍从废钒催化剂中回收钒的理论基础、工艺方法以及回收过程三废的治理。