活性中间体失水甘油基三甲基氯化铵的性质研究

以环氧氯丙烷和三甲胺为原料 ,常温下合成活性中间体失水甘油基三甲基氯化铵 (GTA)。通过对GTA的吸水性和水解性的定量分析可知 :温度上升水解加快 ,吸水减慢 ;吸水与水解都随时间延长加强。在较低浓度的GTA水溶液中 ,随时间的延长GTA逐渐水解失效 ,但质量分数为 70 %～ 80 %的GTA稠浆的分解速率常数却很小。     

氯化胆碱合成工艺的研究

在氯化胆碱的作用下,三甲胺与氯乙醇反应合成氯化胆碱。讨论了影响产品收率及纯度的主要因素。实验发现氯化胆碱有自催化作用,在优化工艺条件下,氯化胆碱的收率达到95.8%,纯度达到98.0%。该工艺具有操作简单、易分离、易干燥、收率高、纯度高、成本低、易推广等优点。     

复合催化法合成对硫磷

研究了以三甲胺作亲核催化剂、季铵盐A作相转移催化剂、水和极性有机溶剂B作双溶剂、亲核—相转移复合催化法合成对硫磷的方法,收率可达99％。     

蓝圆鲹在不同腌制条件下三甲胺和二甲胺含量变化规律

目的：研究蓝圆鲹在不同腌制条件下三甲胺和二甲胺产生的规律。方法：以蓝圆鲹腌制过程中产生的三甲胺(TMA)和二甲胺(DMA)为考察指标,分别考察温度、盐和鱼质量比、食盐种类和腌制时间对TMA和DMA含量的影响。结果：25℃腌制时,随着腌制时间的延长,TMA和DMA的含量不断增加,盐和鱼质量比越低,TMA和DMA的含量越高;4℃腌制时,盐和鱼质量比为1:3组产品中TMA和DMA的含量最低,盐和鱼质量比1:5次之,盐和鱼质量比1:8最高;粗盐腌制的咸鱼中TMA含量较精盐腌制高,DMA含量较精盐腌制低。结论：综合分析盐的种类、腌制时间、温度、盐和鱼质量比对蓝圆鲹在腌制过程中TMA和DMA的变化规律,结合人的口感对盐的接受度及对市售咸鱼中含盐量的调查,确定采用精盐在4℃,盐和鱼质量比为1:5的条件进行腌制。     

Synthesis of Chloroaluminate Ionic Liquids and Use for Olefin Reduction in FCC Gasoline

Abstract

Room temperature ionic liquids (RTILs) are mainly referred to melting salt systems composed by organic cations and organic or inorganic anions that exhibit liquid-like behavior at or around room temperature. Chloroaluminate room temperature ionic liquid (chloroaluminate RTILs) is one kind of RTIL synthesized by chloride quaternary ammonium salts and anhydrous AlCl₃. Three kinds of chloroaluminate RTILs were synthesized using trimethylamine hydrochloride (TA), 1-butylpyrinium chloride (BPyC), or 1-methyl-3-alkylimidazolium (BMIC), respectively, with anhydrous AlCl₃ and their application in reducing the content of olefin in FCC gasoline from the Jinzhou Petrochemical Corporation was studied. The effects of chloroaluminate RTIL component and operation conditions on olefin reduction were investigated as well as the repeatability of chloroaluminate RTILs. The results show that at room temperature, when the ratio of anhydrous AlCl₃ to quaternary ammonium (mole/mole), the solvent-oil ratio (g/g), and the reaction time were 2/1, 20/100, and 1/2 h, respectively, the content of olefin in FCC gasoline was deduced more than 30%. The chloroaluminate RTILs could be used at least four times on the basis of keeping their activity.     

Suitability of Volatile Amines as Freshness Indexes for Iced Mediterranean Hake

Batches of gutted Mediterranean hake (Merluccius merluccius var. Mediterraneus) were stored, in different seasons of the year, for up to 20 d in ice. Changes in trimethylamine (TMA‐N), total volatile bases (TVB‐N), P‐ratio and trimethylamine oxide (TMAO) were measured; sensory evaluation of raw and cooked hake samples was also carried out. Similar profiles were observed between the different trials for all the parameters studied. TVB‐N was not correlated with the time of ice storage, and proved to be better as a spoilage index than a freshness one. In contrast, TMA‐N appears to be a good index of hake quality, and the value of 5 mg/100g offish seems an appropriate limit of acceptability. P‐ratio was a poorer index of freshness than was TMA‐N.     

Mass transfer and reaction of trimethylamine in a three-phase biological reactor

A model system, consisting of a mixed culture of microorganisms, was used to study the performance of a bench-scale packed bed bubble column (PBC) bioreactor treating trimethylamine. Three mesophilic bacterial strains were selected, mixed and acclimatized to grow with trimethylamine as the sole carbon source; degradation kinetic constants were determined for a bacterial suspension system. Gas transfer to the liquid phase was modelled in order to characterize solute transport and availability into the biofilm. The overall performance of the system is discussed based on mass transfer considerations.     

Dimethylamine, trimethylamine, and biogenic amine formation in high-pressure processed semidried squid (Todarodes pacificius) during refrigerated storage

The quality properties of semidried squid treated with high-pressure processing (HPP) were investigated during refrigerated storage. The vacuum-packed semidried squid samples were subjected to 500 MPa for 0 min (HPP-0), 5 min (HPP-5), and 10 min (HPP-10) by using a custom-made high-pressure processor and stored at a refrigerated temperature for 28 d. The populations of indigenous psychrotrophic and mesophilic bacteria were effectively reduced by approximately 1 and 2 log CFU/g at the HPP-10 treatment, respectively. Compared to the control, the bacterial counts in HPP-treated semidried squid samples were maintained at low levels throughout the storage period. The increase in the amounts of dimethylamine (DMA) and trimethylamine (TMA) was more pronounced at the unpressurized control than at the HPP treatments. The production of biogenic amines (BAs) varied with HPP treatment during refrigerated storage. Therefore, the application of HPP may provide a significant improvement in the safety and quality of semidried squid.     

三甲铵乙内酯(甜菜碱)的合成

介绍了以氯乙酸钠和三甲胺为原料合成三甲铵乙内酯（甜菜碱）的方法,以室温为起始反应温度反应０．５ｈ,然后分别于５０℃～５５℃和８０℃～８５℃反应１ｈ,以强酸性阳离子交换树脂为反应液的分离提纯物质。其收率超过９７％,产品纯度达到９８．５％。该法具有操作简便、反应时间短、反应条件温和、产品纯度高等优点。