钯－膦－酸体系催化叔丁醇羰化制备异戊酸酯

研究了Ｐｄ（ＯＡｃ）２－ＰＰｈ３－ｐ－Ｔｓ催化剂体系存在下，叔丁醇羰化生成异戊酸酯的反应．典型的反应条件是：温度１２０～１６０℃，压力３．０～７．０ＭＰａ，Ｐｄ浓度３．６ｍｍｏｌ／Ｌ，ｎＰｄ∶ｎＰＰｈ３∶ｎｐ－Ｔｓ＝１∶３０∶８０，时间１２～２４ｈ．在上述反应条件下，叔丁醇羰化生成异戊酸酯的产率为１１．０％～８３．６％，选择性为１３．１％～９５．０％．     

蔗糖酯示波极谱分析法的研究

蔗糖酯分子在碱性条件下，加热水解为蔗糖和硬酯酸，在ｐＨ＞１０的ＮＨ＿３·Ｎ＿２Ｏ－（ＮＨ＿３）＿３Ｃ＿６Ｈ＿５Ｏ＿７体系中，于示波极谱仪上，峰电位─０．９１Ｖ处出现一灵敏度高和稳定性好的极谱图，其浓度从０．０２～０．２８ｍｇ／ｍＬ与峰电流呈线性关系，最低检出限为０．００４ｍｇ／ｍＬ，相对标准偏差为１．３％。     

二氧化碳与环氧丙烷共聚稀土改性羧酸锌催化剂的研究(I)催化剂的制备和活性评价

用稀土氧化物Ｌｎ２Ｏ３（Ｌｎ： Ｌａ, Ｎｄ, Ｅｕ, Ｈｏ, Ｙｂ, Ｓｍ ）对戊二酸锌进行改性, 制备出新催化剂． 在８０ ℃、３．０～３．５ ＭＰａ 条件下, 该催化剂催化二氧化碳与环氧丙烷共聚, 反应时间为６．５～７．０ ｈ, 催化活性达到３．０～３．４ ｇ ｐｏｌｙｍ ．／（ｇ ｃａｔ．·ｈ）, 转化率７０．８％ ～７９．７％ , 共聚物中碳酸酯单元分数４８．４％ , 产品热分解温度２３８．１ ℃．     

阿斯美胶囊中四种组分的高效液相色谱分析

建立了反相高效液相色谱法测定阿斯美胶囊中氨茶碱、盐酸甲氧非那明、马来酸氯苯那敏及那可汀四种组分的含量。色谱柱为ＳｐｈｅｒｉｓｏｒｂＣ８，５μｍ，２００ｃｍ×４０ｍｍＩＤ，流动相为体积分数０５％的三乙胺溶液（磷酸调节ｐＨ５５）＋乙腈＋甲醇（５５０＋３６８＋８２），检测波长为２６４ｎｍ，线性范围分别为：氨茶碱３１２５～２５０ｍｇ／Ｌ，γ＝０９９９６，盐酸甲氧非那明１５６２５～１２５０ｍｇ／Ｌ，γ＝１００００，马来酸氯苯那敏２５～２００ｍｇ／Ｌ，γ＝０９９９９，那可汀８７５～７００ｍｇ／Ｌ，γ＝０９９９９；回收率（ｎ＝３）分别为１０１２％，１００８％，９９９％，９９５％；精密度：日内平均ＲＳＤ（ｎ＝６）分别为０７％，０４％，０４％，０６％；日间平均ＲＳＤ（ｎ＝３）分别为１０％，１０％，１１％，１２％。     

1,3-二烯基-1,1,3,3-四甲基二硅氧烷/苯乙烯共聚合的环化率与竞聚率

对１３０℃下１，３ 二烯基 １，１，３，３ 四甲基二硅氧烷（ＤＶＤＳ）／苯乙烯（Ｓｔ）的溶液环化共聚合动力学进行了研究．根据低转化率（＜１０％）的共聚物组成及环状结构比例，通过参数估计方法，求得环化率与竞聚率，分别为ｒ１＝０１０２、ｒ２＝３４８、ｒｃ＝００２１０、Ｋｃ＝３８１ｍｏｌ／Ｌ、Ｋ′ｃ＝０３８９ｍｏｌ／Ｌ，同时得到它们９５％置信概率的联合置信区间及其交互影响的联合置信区间．表明ＤＶＤＳ的反应活性较Ｓｔ低，其非环状结构自由基具有较强的分子内环化反应能力；环的位阻效应使环状结构ＤＶＤＳ自由基的活性低于其非环状结构自由基．     

2—3,5—二氯—2—吡啶偶氮）—5—二甲氨基苯胺与铂（Ⅳ）显色反应的研究

研究了２－（３，５－二氯－２－吡啶偶氮）－５－二甲氨基苯胺与铂（Ⅳ）的显色反应，在ｐＨ３．５～６．０醋酸－醋酸钠介质中，沸水浴加热２５ｍｉｎ，试剂与铂（Ⅳ）形成１：４的紫色配合物，再提高酸度至２．９～４．０ｍｏｌ／Ｌ盐酸溶液，其最大吸收峰红移至６３０ｎｍ灵敏度显著提高，表观摩尔吸光系数ε６００＝７．０×１０＾４Ｌ．ｍｏｌ＾－１．ｃｍ＾－１。铂含量在０～３２μｇ／２５ｍＬ范围内符合比耳定律，大多数常     

抑制动力学分析法测定痕量铈

１引言研究了铈（Ⅲ）阻抑Ｈ２Ｏ２氧化水杨基荧光酮（ＳＡＦ）褪色的反应。反应对铈（Ⅲ）为一级反应，表观活化能为２８．７５ｋＪ／ｍｏｌ。据此建立了测定痕量铈的动力学分析法。测定条件为：ＳＡＦ：４．０ｘ１０－５ｍｏｌ／Ｌ，Ｈ２Ｏ２：０．０１０％，ＮａＯＨ：２．０ｘ１０－２ｍｏｌ／Ｌ，５０℃。线性范围０．０４～０．４４ｍｇ／Ｌ，检测限为０．０２ｍｇ／Ｌ。当溶液中的铈含量为０．１６ｍｇ／Ｌ时，３～８倍量的轻稀土，５～１１倍量的重稀土及同倍量铀和钍不干扰测定。２实验部分２．１试剂和仪器铈（Ⅲ）标准溶液：２０…     

铂－锇共显色衍生配合物的高效液相色谱研究

研究了Ｏｓ（Ⅱ）和４，４’二（二乙氨基）苯硫酮与Ｐｔ（Ⅱ）共显色所衍生的配合物，于ＮｕｃｌｅｏｓｉｌＣ＿８柱上，用含３×１０￣（－３）ｍｏｌ／ＬＤＬ－樟脑－１０－磺酸和０．０２ｍｏｌ／ＬＨＡｃ－ＮａＡｃ（ｐＨ３．５）的乙腈－丙酮－水（７２：５：２３，Ｖ／Ｖ）作流动相（１．０ｍＬ／ｍｉｎ）分离并检测。线性范围为０．２～４．０μｇ／ｍＬＰｔ；检测限为１．０ｎｇＰｔ。此方法已应用于抗癌药物顺铂和卡铂的分析。     

丙醛均相催化加氢制丙醇的研究

系统地研究了在４．０ＭＰａ氢压下，反应温度、催化剂浓度、溶剂等对丙醛均相加氢制正丙醇反应的影响，得出最佳反应条件为：氢压４．０ＭＰａ、温度８０℃，ＲｕＣｌ３·３Ｈ２Ｏ为催化剂前体，用量９８ｍｇ（０．３５ｍｍｏｌ），ＰＰｈ３为３９３ｍｇ（１．５ｍｍｏｌ），Ｒｕ／Ｐ摩尔比为１／４，ＤＭＦ为溶剂．在此条件下，丙醛转化率和正丙醇选择性可分别达９９％和９５％以上．求出了不同反应温度下的反应速度常数．以ＲｕＣｌ３－ＰＰｈ３为催化剂体系，丙醛加氢的活化能为７７．６２ｋＪ／ｍｏｌ     

铂—钯共显色衍生络合物的高效液相色谱研究

研究了Ｐｄ（Ⅱ）和４，４＇－二（二乙氨基）苯硫酮（ＢＤＰＴＫ）共显色所生成的Ｐｔ（Ⅱ）络合物，于Ｎｕｃｌｅｏｓｉｌ Ｃ８柱上，用含３×１０＾－３ｍｏｌ／Ｌ ＣＳＡ和０．０２ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ（ｐＨ３．５）的乙腈－丙酮－水（７２：５：２３，Ｖ／Ｖ）作流动相（１．０ｍｌ／ｍｉｎ）分离并检测。Ｐｔ的校正曲线的线性范围为０．２～３．０μｇ／ｍｌ，Ｐｔ检测限为０．７ｎｇ。此方法已应用于抗癌药物顺铂     

酸性离子液体催化脂肪酸甲酯聚合制备二聚酸甲酯

 以 Brönsted-Lewis 酸性离子液体为催化剂, 用于催化生物柴油中不饱和脂肪酸甲酯聚合制备二聚酸甲酯反应, 考察了催化剂种类、催化剂用量、反应温度和时间等因素对聚合反应性能的影响, 得到较佳的反应条件. 结果表明, 当以 1-(3-磺酸)-丙基-3-甲基咪唑氯锌酸盐[HO3S-(CH2)3-mim]Cl-ZnCl2 (ZnCl2 摩尔分数为 0.67) 为催化剂, 生物柴油 15 g, m(生物柴油):m(离子液体) = 15:1, 于 240 oC 下反应 6 h 时, 二聚酸甲酯收率为 63.2%, 其中三聚体含量小于 5%. 另外, 该催化剂重复使用 5 次后, 二聚酸甲酯收率仍超过 63%, 表明其具有较好的重复使用性能. 离子液体的 Brönsted 和 Lewis 酸位的协同效应显著提高了其催化活性.     

New hydrolysis method for extremely small amount of lipids and capillary gas chromatographic analysis as n(O)-tert.-butyldimethylsilyl fatty acid derivatives compared with methyl ester derivatives

The organic basic solution, 1 M tetramethylammonium hydroxide (TMAH) in methanol, was employed for the hydrolysis of extremely small amounts of lipids compared to the classical inorganic basic solution, 1 M KOH in ethanol. The hydrolysed fatty acids were derivatized as N(O)-tert.-butyldimethylsilyl (tBDMSi) esters with N-methyl-N-(tert.-butyldimethylsilyl) trifluoroacetamide (MTBSTFA) and compared with the classical derivatives, the methyl esters, made by the BF3-methanol method. Recoveries of fatty acids determined on the standard fatty acids and soybean oil hydrolysed with TMAH were high: about 1.1-2.1- and 2.0-5.4-times, respectively, in all fatty acids compared with the hydrolysis by KOH regardless of derivatization method. The relative standard deviations (RSDs) on the recoveries of standard fatty acids were less than 5% when hydrolysed with TMAH, regardless of derivatives, but when hydrolysed with KOH, RSDs were more than 5% for most fatty acids, especially for long-chain fatty acids. The RSDs on the recoveries of fatty acids on the soybean oil were also very high in the KOH hydrolysis. Fatty acid compositions of soybean oil were similar in the main fatty acids regardless of hydrolysis methods, but showed slightly different values, depending on the methods of derivatization. RSDs were also very high in the KOH hydrolysis. In view of these results, precision of analysis by KOH hydrolysis was very poor, so we could not rely on the data. On the other hand, the reliability of data by TMAH hydrolysis method was very high, so it is a useful new hydrolysis method for extremely small amounts of lipid samples. Both derivatives of 35 standard fatty acids were successfully separated on a HP-1 nonpolar capillary column. tBDMSi derivatives were completely resolved in 70 min by 295 degrees C. In the methyl ester derivatives it took about 80 min to get satisfying resolution, but these derivatives were completely resolved by 250 degrees C. The sensitivity of tBDMSi derivatives was about 1.5-6.3-times higher than that with methyl ester derivatives. The stability of tBDMSi derivatives was constant for about 144 h except arachidic, docosahexanoic, behenic and heneicosanoic acids, which were stable for only 86 h.     

Synthesis of Biodiesel from Palm Oil in Capillary Millichannel Reactor: Effect of Temperature,Methanol to Oil Molar Ratio,and KOH Concentration on FAME Yield

Application of microtube reactor for the continuous synthesis of biodiesel has been widely studied due to excellent performance in liquid-liquid phase reaction. In order to commercialize biodiesel production, integration of microtube reactor is highly recommended. Therefore, in this study, synthesis of biodiesel was carried out in capillary millichannel reactor with inner diameter of 1.59 mm using methanol and potassium hydroxide (KOH) as base catalyst with palm oil as a feedstock. The influences of reaction temperature, methanol to oil molar ratio, and KOH concentration on the production of fatty acid methyl ester (FAME) were examined. The highest FAME yield was achieved at 60 ˚C with 23:1 methanol to oil molar ratio and 5 wt% of KOH concentration.     

Isolation of 6,9,12,15-Hexadecatetraenoic Fatty Acid (16:4n-1) Methyl Ester from Transesterified Fish Oil by HSCCC

Fish oil is considered a healthy food due to the presence of large amounts of polyunsaturated fatty acids (PUFAs), especially in the form of n-3 fatty acids 5,8,11,14,17-eicosapentaenoic acid (20:5n-3; EPA) and 4,7,10,13,16,19-docosahexaenoic acid (22:6n-3; DHA). However, fish oil is known to contain many other PUFAs, some of which are uncommon and whose bioactivity is scarcely investigated. In this study, we isolated the rare PUFA 6,9,12,15-hexadecatetraenoic fatty acid (16:4n-1) which bears a double bond on the terminal carbon from fish oil in form of its methyl ester. We used high-speed counter-current chromatography (HSCCC) for the fractionation of 500 mg-portions of fatty acid methyl esters prepared from a fish oil capsule and investigated the fractions by GC/MS. Twenty-eight 13-mL fractions were collected and fatty acid methyl esters were detected in fractions 11–23. The elution was carried out in normal phase mode, providing the long-chained saturated and monoenoic fatty acids first. More than 100 fatty acids ranging from 10:0 to 26:0 could be identified in the HSCCC fractions, and most of them were polyunsaturated. The reproducibility of the HSCCC method was shown by repeated injection of the fish oil and the fractions containing 6,9,12,15-hexadecatetraenoic fatty acid (16:4n-1). The late eluting 16:4n-1 methyl ester was isolated in pure form and its structure was verified.

     

Production and Characterization of Biodiesel from Tung Oil

The feasibility of biodiesel production from tung oil was investigated. The esterification reaction of the free fatty acids of tung oil was performed using Amberlyst-15. Optimal molar ratio of methanol to oil was determined to be 7.5:1, and Amberlyst-15 was 20.8wt% of oil by response surface methodology. Under these reaction conditions, the acid value of tung oil was reduced to 0.72mg KOH/g. In the range of the molar equivalents of methanol to oil under 5, the esterification was strongly affected by the amount of methanol but not the catalyst. When the molar ratio of methanol to oil was 4.1:1 and Amberlyst-15 was 29.8wt% of the oil, the acid value decreased to 0.85mg KOH/g. After the transesterification reaction of pretreated tung oil, the purity of tung biodiesel was 90.2wt%. The high viscosity of crude tung oil decreased to 9.8mm²/s at 40 °C. Because of the presence of eleostearic acid, which is a main component of tung oil, the oxidation stability as determined by the Rancimat method was very low, 0.5h, but the cold filter plugging point, −11 °C, was good. The distillation process did not improve the fatty acid methyl ester content and the viscosity.     

Lipase-Catalyzed Transesterification of Rapeseed Oil for Biodiesel Production with tert-Butanol

Biodiesel is a fatty acid alkyl ester that can be derived from any vegetable oil or animal fat via the process of transesterification. It is a renewable, biodegradable, and nontoxic fuel. In this paper, we have evaluated the efficacy of a transesterification process for rapeseed oil with methanol in the presence of an enzyme and tert-butanol, which is added to ameliorate the negative effects associated with excess methanol. The application of Novozym 435 was determined to catalyze the transesterification process, and a conversion of 76.1% was achieved under selected conditions (reaction temperature 40 °C, methanol/oil molar ratio 3:1, 5% (w/w) Novozym 435 based on the oil weight, water content 1% (w/w), and reaction time of 24h). It has also been determined that rapeseed oil can be converted to fatty acid methyl ester using this system, and the results of this study contribute to the body of basic data relevant to the development of continuous enzymatic processes.     

Optimization of Fatty Acid Determination in Selected Fish and Microalgal Oils

The use of ten fatty acid methyl ester reference standards coupled with a detailed quantification method was shown to significantly optimize the fatty acid determination of selected fish and microalgal oils when compared to methods that use only one reference standard (C19:0 or C23:0) as a relative response factor. When using the mixture of ten reference standards after transesterifying oils with NaOH/BF₃, determination of total fatty acids, eicosapentaenoic acid and docosahexaenoic acid improved by an average of 7.3, 11.5 and 8.4%, respectively. Furthermore, improvements of 13.9, 18.9 and 6.8% of total fatty acids, EPA and DHA, respectively, were obtained when using the mixture of reference standards for fatty acid determination after directly extracting and transesterifying oil contained in microalgal cells with a mixture of methanol, HCl and chloroform. Fatty acid methyl ester standards dissolved in isooctane showed <5% variability throughout 130 days of stability testing when stored at ?20 °C. The optimized method can be used for improving the quantification of fatty acids in both oils (fish and microalgal oils) and dry microalgal cells.     

Batch (one- and two-stage) production of biodiesel fuel from rapeseed oil

Biodiesel fuel is an alternative and renewable energy source, which may help to reduce air pollution, as well as our dependence on petroleum for energy. Several processes have already been developed for the production of biodiesel. Alkali-catalyzed transesterification with short-chain alcohols, for example, generates high yields of methyl esters in short reaction times. In this study, we have evaluated the efficacy of batch (one- and two-stage) transesterification of rapeseed oil in the production of rapeseed methyl ester. The conversion of rapeseed oil exhibited similar reaction patterns and yields in 30- and 1-L reaction systems. Approximately 98% of the rapeseed oil was converted at 400 rpm within 20 min, under the following conditions: 1% (w/w) KOH, 1∶10 methanol molar ratio, and at 60°C. In the 30-L, two-stage transesterification process, approx 98.5% of the rapeseed oil was converted at a 1∶4.5 molar ratio and 1% (w/w) KOH at 60°C for 30 min (first reaction condition), and at a 1∶1 molar ratio and 0.2% (w/w) KOH at 60°C for 30 min (second reaction condition).     

On the isomerization of ent-kaurenic acid

Kaurenic acid (1a) is a tetracyclic diterpene that has an exocyclic double bond at delta16. Isokaurenic acid (2a) has an endocyclic delta15double bond. This compound has been isolated from Espeletia tenore (Espeletinae), a resinous plant from the Venezuelan Andes, but its occurrence is rare. In order to obtain a larger amount of 2a, the isomerization of la, which is easily obtained from other Espeletinae, was tried. Kaurenic acid methyl ester (1b) was treated with dil. HCl in CH3Cl/EtOH, after 6 h under reflux a yield of 41.5% isokaurenic acid methyl ester (2b) was obtained but 35.7% 16alpha-ethoxy-kauran-19-oic acid methyl ester (3b) had formed as a byproduct. Treating 1b with CF3COOH in refluxing CH2Cl2 permitted to obtain a yield of 66.6% of 2b in 4 h and only traces of 16alpha-hydroxy-kauran-19-oic acid methyl ester (3a) as a byproduct. Both isomers were separated on a silica gel column impregnated with 20% AgNO3. Treating 2b with KOH in refluxing DMSO yielded pure isokaurenic acid, no back isomerization was observed.     

Effect of Bio-based Catalyst in Biodiesel Synthesis

A cost-effective and environmentally friendly biodiesel synthesis has drawn attention in recent research activities. Used cooking oil which is known as waste is used in this study. The objectives of this research were to study an effect of biobased-catalyst which is used as supporting catalyst in simultaneous ozonolysis and transesterification for biodiesel synthesis and to study the effect of two steps process in biodiesel synthesis. The bio-based catalyst used in this process was empty palm bunch ash which was used as supporting catalyst for KOH. Two steps reaction were designed, the first step was run in a reactor at 30 °C with a continuous supply of ozone gas for 3 hours to cleave the unsaturated fatty acids at the double bonds. The second step was a follow up process after the first step without a supply of ozone gas, the temperature was increased up to 60 °C and the reaction continue for two hours. The second step aimed to convert saturated fatty acid which was not yet fully converted at the first step. Results of this study showed that 1.5% of KOH gave better performance in producing short chain methyl esters compared to 1% of KOH in the first step process at various percent weight of ash. The highest short chain methyl esters and long chain methyl esters produced in the first step process were 85.722 mg/liter and 655.286 mg/liter respectively, which was used 17.3 weight % ash and 1.5 weight % KOH. Short chain methyl esters were produced as a result of unsaturated fatty acid cracked by ozonolysis. It is confirmed that a simultaneous ozonolysis and transesterification occurred in the first step process. In conclusion, the presence of bio-based catalyst as supporting catalyst for KOH to produce higher total methyl esters has been effective. The second step process in this experiment was not effective since the effect of reaction time can enhance the hydrolysis of esters as a reverse reaction of transesterification, resulted in loss of esters.