络合法浓缩植物油脱臭馏分中天然维生素E

采用尿素络合处理法预浓缩植物油脱臭馏分中的维生素E,用单因素平行试验对络合处理过程中醇、水分含量、回流时间、冷析温度、冷析时间、原料的比例等影响因素进行考察,并用高效液相色谱对样品进行分析,得出最佳条件为：以95％的乙醇为溶剂、回流反应30min、在0℃下冷析5h、脱臭馏分：尿素：醇的质量比为1：4：6,在此条件下将生育酚含量由1．50％提高至5．04％。     

络合法浓缩植物油脱臭馏份中天然维生素E

采用尿素络合处理法预浓缩植物油脱臭馏份中的维生素E，用单因素平行试验对络合处理过程中醇、水分含量、回流时间、冷析温度、冷析时间、原料的比例等影响因素进行考察，并用高效液相色谱对样品进行分析，得出最佳条件为．以95％的乙醇为溶剂、回流反应1h、在0℃下冷析5h、脱臭馏份：尿素：醇为1：4：6，在此条件下将生育酚浓度由1．50％提高至5．04％。     

抚顺页岩油综合利用的研究

为充分合理地利用抚顺页岩油资源,对抚顺页岩油柴油馏分(350℃)进行络合精制实验。结果表明:当溶剂比为0.2、络合比为0.25、络合温度为60℃、络合时间为4h的络合精制条件下,精制油的碱性氮含量由0.30%降低到0.069%。抚顺页岩油柴油馏分通过实验室络合精制后,页岩柴油的碱性氮含量由0.30%降到0.020%。结果表明:应将该页岩油的柴油馏分进行精制生产合格柴油,或是作为低凝点柴油的调和组分;蜡油馏分溶剂脱蜡后,蜡膏通过精制后生产商品石蜡,脱蜡油精制后作为中速柴油机燃料、热裂化或加氢裂化的原料油。     

用5A分子筛分析石油馏分中的C_5～C_(14)正构烷烃

测定分子量较低(C_6以下)馏分中正构烷烃的含量,用气液色谱法是方便而准确的。对180℃以上馏分,尿素络合法比较常用。但此法有一定的缺点,因为不仅是正构烷烃,而且异构烷烃、烃基环烷烃及烃基苯等,只要它们带有足够长的直链,也能和尿素络合;甚至3-甲基庚烷、2-甲基壬烷等,在可络合的正烷烃“诱导”下,也能生成络合物。其次,尿素与正构烃的络合反应是可逆的,因而生成络合物的反应难于进行到十分完全。此外,此法需要消耗较多的分析油样及大量石油醚(用作稀释剂)。对C_7～C_9间的馏分,由于相应的尿素-正构烃络合物很不稳定,也不能用尿素络合法分析。用一般气液色谱法分析该馏分亦有不少困     

柳树叶中总黄酮含量测定

采用乙醇回流提取法,以亚硝酸钠、硝酸铝、氢氧化钠为试剂,芦丁为对照,研究柳树叶中黄酮含量的测定。利用正交实验对柳树叶中黄酮含量测定方法进行优化。以乙醇浓度、回流时间、回流温度、料液比为因素,总黄酮显色液的吸光度为指标进行实验。得到的最佳条件为:乙醇浓度50%,料液比1∶30,回流时间为1h,回流温度为70℃,在最佳条件下的总黄酮含量为18.92mg/g。     

碳酸乙烯酯法合成N-芳基-2-噁唑烷酮

以纳米ZnO为催化剂,通过尿素的乙二醇醇解反应合成碳酸乙烯酯,实验表明:在常压下,尿素与干燥的乙二醇比例为1∶1,150℃反应8h,碳酸乙烯酯的产率为90.9%。再以碳酸乙烯酯和芳胺为原料,在Na-Y分子筛和K2CO3催化下,DMF为溶剂,回流反应3h,合成标题化合物,产率50%～85%,并利用元素分析、1HNMR、13CNMR、IR对目标化合物进行了表征。     

Fe3O4@SiO2的表面改性

采用溶胶凝胶法在磁性Fe3O4纳米粒子的表面包覆SiO2,采用正交试验法,以表面Si-OH含量为指标,考察温度、时间和醇/水三因素对表面Si-OH含量的影响,利用X射线光电子能谱分析(XPS)测试Fe3O4@SiO2复合粒子表面Si-OH含量,结果表明在80%、回流时间为1h、醇/水为6∶1是改性Fe3O4@SiO2的...     

水力空化提高醇酮焦油轻质组分的研究

为了提高己二酸生产过程中产生的副产物醇酮焦油的利用率,利用水力空化技术提高醇酮焦油中≤160℃轻质组分的含量,通过单因素实验分别考察了温度、入口压力、V(甲醇)∶V(水)、pH值和循环时间对醇酮焦油轻质化的影响。在单因素实验的基础上,增加正交试验优化确定入口压力、循环时间、V(甲醇)∶V(水)对醇酮焦油轻质化的影响,当温度为80℃、入口压力为2.5 MPa、V(甲醇)∶V(水)为1.0∶1.0、pH值为4和循环时间为70 min时,≤160℃馏分变化百分率为37.62%。同时,对水力空化过程中的能量利用进行了计算,当入口压力为2.5 MPa、循环时间为70 min时,耗散实际能量所用的总能量为5.78×10⁶ kJ·m^-3。     

利用尿素复合溶液从风化煤中提取水溶腐植酸和生成腐植酸络合酰胺态氮的研究

腐植酸(折纯干基)∶氢氧化钾∶尿素∶自来水=1∶0.28∶0～0.56∶14(质量比),反应温度80℃,反应时间2 h,水溶腐植酸提取率在76.9%～88.48%,尿素可以增加提取率11.58%,尿素反应的腐植酸络合酰胺态氮在1.08%～3.38%。尿素在0.04比例时,乙醇溶解物和离心后残渣中的酰胺态和铵态氮最少,尿素反应最彻底;尿素在0.16比例时,尿素参与反应的络合酰胺态氮最高;尿素在0.32比例时,是提取水溶腐植酸的最佳用量。尿素在碱性条件下可以促进和腐植酸的反应,提高腐植酸的提取率。     

延丹丸提取工艺优化

目的:延丹丸醇提取工艺的优化。方法:以山楂中熊果酸含量为考察指标,对延丹丸醇提取工艺中提取溶剂量、提取时间、乙醇浓度、提取次数4个因素进行优化。结果:最佳提取工艺条件为:4倍量65%乙醇回流提取1次,每次1h。结论:在此条件下,延丹丸醇提取工艺稳定可行,能有效提高山楂中熊果酸的含量。     

菜籽油馏出物中维生素E的分子蒸馏工艺研究

介绍了菜籽油馏出物中维生素E的分子蒸馏工艺过程,考察了分子蒸馏各操作参数对维生素E的含量和收率的影响。研究结果表明:当操作压力为0.1Pa,蒸馏温度为180℃,进料流量250mL/h,进料温度170℃,刮膜速度150 r/min时,维生素E的一次收率可达65.38%,可得含量为51.72%的维生素E产品。利用分子蒸馏多级操作,可满足维生素E的进一步提纯要求。     

Extraction of α‐tocopherolquinone from vegetable oil deodorizer distillate waste

In industry, deodorizer distillate waste is one of the last products of refined edible oil after the removal of commercially important value components such as fatty acids, sterols, squalene, and vitamin E. The refinery process itself is the cause of a significant amount of loss in vitamin E due to distillation and thermal oxidation. The distillate waste has a very limited commercial value, therefore requires additional costs for a safe environmental disposal. One of the main vitamin E oxidation products found in large quantities in oil waste is tocopherolquinone (TQ). A literature search has revealed that in the past several techniques including a variety of solvent extractions, saponification, or column extraction have been used for TQ isolation with limited success. The present study is a new cost‐effective liquid–liquid extraction method developed to isolate α‐TQ from vegetable oil steam distillate or distillate waste. High recovery results ranging from 31 to 120% were obtained depending on the ratio between the sample and three different organic extraction solvents (acetonitrile, methanol, and hexane) combined.     

Relationships among the variables involved in the physical refining of olive oil using nitrogen as stripping gas

The use of nitrogen as stripping gas has been proposed as an interesting alternative to steam in physical refining and deodorization. A 2³ experiment has been carried out with olive oil in a 200 kg discontinuous deodorizer in order to study the relationships among the independent variables involved in the physical refining process - nitrogen flow, temperature and oil load. The results have shown that at about 245°C and with a nitrogen stripping gas flow of 1500 l/kg.h it is possible to get refined oil with less than 0,4% of free fatty acids and quality indices adjusted to the ECC standards. Using these conditions the acidity is practically independent of the oil load within the limits of the experiment (125–175 kg of oil load).     

Extraction of tocopherols from the deodorized distillate of soybean oil with liquefied petroleum gas

Deodorizer distillate, produced during the last processing step of edible oil refinement, is a mixture of tocopherols, sterols, fatty acids, glycerides, hydrocarbons, water and other materials. The amount of tocopherols in deodorizer distillate is large enough to be considered as raw material for vitamin E preparation. In this work, separation of tocopherols from sterols has been achieved using liquefied petroleum gas (LPG) extraction. LPG was chosen as extraction solvent in order to improve extract recovery and prevent tocopherol degradation.     

紫草油中亚麻酸的分离与提纯方法的研究

以中国东北地区产的紫草种籽为原料 ,气相色谱内标法进行跟踪定量分析 ,采用改进的尿素包合法 ,对从紫草种籽油中分离提纯亚麻酸的诸工艺条件进行了实验研究。实验结果表明 :每 2 0g紫草油最终可得不饱和脂肪酸甲酯 10 2g ,其中w(亚麻酸甲酯 ) =83 1%。最佳工艺条件为 :(1)水解反应 :m(KOH)∶m (CH3 CH2 OH)∶m(H2 O) =2∶15∶5 ,氮气保护 ,反应温度为 6 0℃ ,酸化时pH =3～ 4 ;(2 )甲酯化反应 :V(混合脂肪酸 )∶V(甲醇 )∶V(浓硫酸 ) =92∶4 0 0∶3;(3)尿素包合 :m(混合脂肪酸甲酯 )∶m(尿素 ) =1∶2 ,包合温度为 - 6℃ ,时间 8h。     

超临界CO2萃取浓缩天然维生素E的研究

以大豆油脱臭馏出物预处理产物为原料,在温度40—60℃、压力9—17 MPa范围内等温、等压和等密度3种条件下分别测定了预处理产物中天然维生素E和脂肪酸甲酯在超临界CO2中的溶解度,并计算了它们之间的相对分离因子。在此基础上,比较了单柱萃取、萃取+精馏和双柱萃取3种超临界CO2逆流浓缩天然维生素E的工艺方案。结果表明,双柱萃取优于其他2种方案。     

Separation of Individual Tocopherols from Soybean Distillate by Low Pressure Column Chromatography

α-Tocopherol, γ-tocopherol and δ-tocopherol were successfully separated and purified from soybean vitamin E concentrate (53% purity, from soybean oil deodorizer distillate) using a low-pressure glass column (500 mm × 25 mm, I.D., packed with silica gel). The effects of eluent, flow-rate and sample loading on separation efficiency were investigated using product purity and recovery as evaluation indices. On the basis of the single factor experiment results, an orthogonal test was designed to optimize the chromatographic separation conditions. The optimum conditions obtained by using analyses of extreme difference and variance are as follows: cyclohexane-ethanol 99.7:0.3 (v/v), flow-rate at 25 ml/min and loading amount being 2 ml (concentration 1 g/ml). Under these optimum conditions, purity of the α-tocopherol, γ-tocopherol and δ-tocopherol were 92.35, 91.23, 89.95%, respectively; the recovery of those products were 35.21, 36.25, 61.25%, respectively. The advantage of this process is that high purity individual tocopherols can be obtained directly from soybean vitamin E concentrate at 53% purity, without additional purification steps.     

1-甲基-2,4,5-三硝基咪唑(MTNI)的合成

以4-硝基咪唑为原料,经硝化、热重排、甲基化等反应合成1-甲基-2,4,5-三硝基咪唑(MTNI),总收率19.4%,纯度>98%,经红外光谱、核磁共振、元素分析等方法表征其结构。研究了反应温度、反应时间等因素对1-甲基-2,4-二硝基咪唑(MDNI)合成及收率的影响,得到了较优的工艺条件:n(2,4-二硝基咪唑)∶n(碘甲烷)=5∶9,反应温度40~45℃,反应时间8h。对硝化反应条件进行了研究,确定了适宜反应时间为1h,反应温度为95℃。     

费托合成高温油相产品中正构烃的分离

以模拟的费托合成高温油相产品为原料,采用尿素包合法从原料中分离正构烃。考察了活化剂的种类、包合反应条件、解包合反应条件等对正构烃分离效果的影响。通过正交实验研究,结果表明：乙醇为较适宜的活化剂;较优反应条件为反应温度5℃,反应时间60min,以1g原料为基准,尿素用量2.75g,乙醇用量3.5mL,水用量1.125mL。在此包合反应条件下,得到1-癸烯的回收率为87.75%,正癸烷的回收率为89.90%。尿素包合物的解包合反应实验结果说明,水的存在有利于解包合反应的进行,得到正构烃回收率较高。用水量为100 mL时,尿素包合物的解包合反应基本完成。     

气相色谱法模拟蒸馏实验测定三混油、蒽油组分及其初点、干点技术的开发与应用

近年来随着色谱技术的发展,利用色谱仪器模拟蒸馏试验已在化工企业得到了应用,我公司已开始利用气相色谱模拟蒸馏试验测定三混油、蒽油馏分的初点、干点、及230℃、270℃、300℃、360℃前的馏出量,通过大量的试验对比,利用色谱数据和蒸馏数据的相关性,求出的关于色谱值和蒸馏值的线性公式,已成功地应用到生产工艺的调节。