haohan异丁烯中的二甲醚等含氧化合物杂质测定专用气相色谱仪GC-FID

           异丁烯是C4烯烃的重要组成之一,主要用作生产丁基橡胶、聚丁烯、烷基酚、甲基叔丁基醚和甲基丙烯酸甲酯等的原料,其中丁基橡胶是重要的军工材料,甲基叔丁基醚是无铅汽油的主要添加剂。

           随着石油化工的快速发展,异丁烯的应用越来越受到重视。异丁烯的工业生产路线主要有硫酸萃取法、树脂法(叔丁醇合成和分解法)、醚化法(甲基叔丁基醚合成和分解法)等。目前国内主要采用醚化法生产路线,硫酸萃取法、树脂法已被淘汰。

            异丁烯产品中杂质的种类和含量与生产工艺密切相关,除了烃类杂质外,早期采用硫酸萃取法和树脂法生产的异丁烯中主要含有C3～C4醇类杂质,而采用醚化法生产的异丁烯产品主要含有二甲醚(DME)、甲基叔丁基醚(MTBE)、甲醇及叔丁醇等杂质。对于异丁烯中的含氧化合物分析,分离C3～C4醇类较为容易,而分离二甲醚却较为困难。因为二甲醚的极性很弱,即使采用强极性的色谱柱如1,2,3-三(2-氰乙氧基)丙烷(简称TCEP)也不能把二甲醚分离出来,所以二甲醚的分离是一大难题。异丁烯的用途不同,对含氧化合物杂质的控制要求差别很大,也给分离和定量分析带来困难。

浩瀚色谱（山东）应用技术开发有限公司采用(φ0.32 mm×25 m×5 μm)毛细管色谱柱对异丁烯中的二甲醚等含氧化合物杂质进行了气相色谱方法研究.结果表明,该色谱柱能很好地分离异丁烯中的二甲醚等含氧化合物杂质;使用液相进样阀液态直接进样保证了试样的代表性.该方法是一种快速、准确、安全地分析异丁烯中二甲醚等含氧化合物杂质的方法。
 

Isobutene is one of the important components of C4 olefins, mainly used as raw materials for the production of butyl rubber, polybutene, alkylphenol, methyl tert butyl ether, and methyl methacrylate. Among them, butyl rubber is an important military material, and methyl tert butyl ether is the main additive for lead-free gasoline.



With the rapid development of petrochemical industry, the application of isobutylene is receiving increasing attention. The industrial production routes of isobutylene mainly include sulfuric acid extraction method, resin method (synthesis and decomposition of tert butanol), etherification method (synthesis and decomposition of methyl tert butyl ether), etc. At present, the main production route in China is etherification, while sulfuric acid extraction and resin methods have been phased out.



The types and content of impurities in isobutylene products are closely related to the production process. In addition to hydrocarbon impurities, early isobutylene produced by sulfuric acid extraction and resin methods mainly contains C3-C4 alcohol impurities, while isobutylene products produced by etherification mainly contain impurities such as dimethyl ether (DME), methyl tert butyl ether (MTBE), methanol, and tert butanol. For the analysis of oxygen-containing compounds in isobutene, it is easier to separate C3-C4 alcohols, but it is more difficult to separate dimethyl ether. Due to the weak polarity of dimethyl ether, even using a highly polar chromatographic column such as 1,2,3-tris (2-cyanoethoxy) propane (TCEP) cannot separate dimethyl ether. Therefore, the separation of dimethyl ether is a major challenge. The use of isobutylene varies greatly, and the requirements for controlling impurities in oxygen-containing compounds vary greatly, which also brings difficulties to separation and quantitative analysis.




Used by Haohan Chromatography (Shandong) Application Technology Development Co., Ltd（ φ 0.32 mm × 25 m × five μ m) A gas chromatography method was used to study the impurities of oxygen-containing compounds such as dimethyl ether in isobutene using a capillary column. The results showed that the column could effectively separate impurities of oxygen-containing compounds such as dimethyl ether in isobutene; The use of a liquid phase injection valve ensures the representativeness of the sample through direct liquid injection. This method is a fast, accurate, and safe method for analyzing impurities in oxygen-containing compounds such as dimethyl ether in isobutylene.