加脂剂合成过程中主要参数的测试原理和方法

加脂剂合成过程相关参数的测定对于合成过程的控制有着十分重要的指导意义.对皮革加脂剂在合成过程中常用的参数测试方法进行了归纳,并详细介绍了皂化值、碘值、过氧化值的测试原理和方法.     

西南菌种站部分酿酒增香酵母产酯性能初探

酯类是白酒中的主要香气成分，本文主要介绍西南菌种站保存的部分酿酒增香酵母在不同发酵培养条件下的产酯能力。试验对7株产酯酵母进行3种培养基、3种培养时间的多配方处理发酵，采用皂化法测定总酯。实验结果表明，菌株SICC 2．644与SICC2．645产酯水平较高，分别达到230．2mg／100mL和171．2mg／100mL；大部分菌株于麦芽汁发酵培养能获得较为理想的产酯测试效果。     

A comparative study of the analytical methods for the determination of polycyclic aromatic hydrocarbons in seafood by high‐performance liquid chromatography with fluorescence detection

This study was performed to establish a rapid analytical method to determine the presence of fourteen polycyclic aromatic hydrocarbons (PAHs) in seafoods by high‐performance liquid chromatography with fluorescence detection (HPLC/FLD). The samples were prepared using two methods: the Quick, Easy, Cheap, Effective, Rugged, Safe (QuEChERS) method and the alkali digestion method. The QuEChERS method involved a convenient and effective solid–liquid extraction and a simple purification. The alkali digestion method was comprised of a liquid–liquid extraction after saponification with potassium hydroxide followed by purification. The limits of detection (LODs) and limits of quantification (LOQs) of the QuEChERS method ranged from 0.05 to 1.60 μg kg^?1, and those of the alkali digestion method ranged from 0.28 to 5.18 μg kg^?1. The repeatability for all target analytes was similar for the two methods, that is, 0.66–4.24% and 0.26–5.75% for the QuEChERS and alkali digestion methods, respectively. At analyte concentrations of 2.5–50 μg kg^?1, the recovery of the QuEChERS method ranged from 86.87% to 115.67% and that of the alkali digestion method ranged from 69.22% to 100.21%.     

催化氧化法制备硬质氧化蜡

实验制备的氧化蜡具有与天然巴西棕榈蜡相近的性能。考察了反应温度、反应时间、空气流速、蜡的选择和用量、催化剂用量等因素对氧化蜡质量的影响。结果表明,最佳工艺条件为:反应温度150～160℃,激发温度180～185℃,反应时间6～8 h,空气流速0.4 m3/h,石蜡用量65.0%,聚乙烯蜡用量20.0%,硬脂酸用量10.0%,氢氧化钙用量2.5%～3.0%,催化剂用量0.02%～0.05%,DTBP用量0.6%～1.0%。得到的产品具有较高的酸值、皂化值和较佳的针入度值。     

毛叶山桐子油中脂肪酸组成分析

以毛叶山桐子毛油为原料,利用容量分析方法测定其酸值、碘值及皂化值。以甲酯化方法对山桐子油进行处理后,用GC-MS法对脂肪酸组成和相对含量进行测定,结果显示其碘值为52．15g·（100g）^-1,皂化值195．39mgKOH·g^-1,主要脂肪酸为反式-9,12-十八碳二烯酸、棕榈酸、棕榈油酸等,反式-9,12-十八碳二烯酸含量最高,达59．54％。     

浓缩- 结晶法制备辣椒碱类化合物工艺

以辣椒油树脂为原料,研究浓缩、皂化和结晶条件对辣椒碱类化合物提取率和纯度的影响。采用单因素和正交试验设计优化辣椒油树脂浓缩和辣椒碱类化合物的提取工艺。结果表明：影响辣椒油树脂浓缩效果的4 个因素是甲醇体积分数＞浸提温度＞甲醇溶液用量＞浸提时间,影响辣椒碱类化合物提取率的4个因素依次为皂化时间＞pH 值＞结晶温度＞ NaOH 质量分数;获得最佳工艺条件：质量分数1.5% 的辣椒油树脂用体积分数80% 甲醇浓缩得到质量分数36% 的辣椒提取物,直接用质量分数10% NaOH 溶液在50℃条件下皂化4h,然后在5℃用稀盐酸调节pH7.0,静置结晶,提取率为86.67%。产品经HPLC 分析,纯度达97.87%。     

制备4-(2’,4’-二氟苯基)-苯酚的工艺研究

研究了 4 ( 2’ ,4’ 二氟苯基 ) 苯酚乙酸酯的水解反应特性。确定了该反应的最佳条件为 :惰性气体保护 ,n(NaOH)∶n[4 ( 2’ ,4’ 二氟苯基 ) 苯酚乙酸酯 ]=4∶1,反应时间 4h ,收率达到96 % ,w[4 ( 2’ ,4’ 二氟苯基 ) 苯酚 ]=98%。并发现 4 ( 2’ ,4’ 二氟苯基 ) 苯酚乙酸酯的纯度对水解反应有重要的影响。     

万寿菊提取物中游离叶黄素的制备及纯化

以万寿菊正己烷提取物为原料,系统地考察了由万寿菊提取物制备游离叶黄素的条件,并对粗产品进行纯化。在单因素试验的基础上,用L16(45)正交试验对游离叶黄素的制备工艺进行优化,以皂化液浓度、液料比、皂化温度以及皂化时间为因素,以游离叶黄素的含量为指标进行试验,得到最佳的制备条件;并对硅胶柱层析纯化的梯度洗脱条件进行摸索;采用薄层色谱扫描法进行测定。确定最佳皂化制备条件是:皂化液为35%的KOH-甲醇,液料比20:1(ml/g),皂化温度55℃,皂化时间4h;在此条件下,可使游离叶黄素的含量由原料中的0.25%上升到45.59%,通过硅胶柱层析纯化后,游离叶黄素的含量可提高到93.55%。     

腈纶皂化制备电流变液悬浮粒子的研究

为了制备无水电流变液用悬浮粒子,研究了腈纶在碱性条件下的多相水解。详细考察了皂化试剂氢氧化钾的用量,皂化时间和温度等皂化条件对皂化程度的影响;讨论了氰基转化过程。研究结果表明,在皂化初期,腈纶分子链上的氰基转化为酰胺基,然后缓慢转化为羧基。给出了一条制备无水电流变液用悬浮粒子的方法,并初步考察了该类电流变液的控光特性。     

Reducing environmental threats of gutter oil: application in fluorite flotation by saponification

In order to reduce the environmental threat of kitchen waste, the gutter oil was transformed into renewable collector by saponification and used for flotation of fluorite. The adsorption characteristics of the collector on fluorite surface were analyzed by X-ray photoelectron spectroscopy (XPS). The influence of the collector dosage and inhibitor dosage on the separation efficiency was analyzed by the flotation test. XPS results show that collector can change the charge characteristics of calcium ions, indicating that the collector has significant adsorption on the fluorite surface. Separation results show that the renewable collector has achieved an excellent effect on fluorite flotation.