低温煤焦油中金属元素的形态分析

Analysis and application of metal speciation in low temperature coal tar

建立了一种简单实用的对煤焦油中的金属进行萃取的方法,采用电感耦合等离子体发射光谱法对萃取后各相中的金属进行定量分析,选取苯甲酸钾、2-苯基苯酚钠盐四水合物、环烷酸钙、环烷酸铁、5,10,15,20-四(4-甲基苯基)-21H,23H-卟吩氯化铁(Ⅲ)5种有机金属模型化合物对比分析了煤焦油中金属元素的存在形态。实验结果表明,该方法消除了油水混合物受热喷溅的安全隐患,还可测定煤焦油中的无机金属和有机金属。低温煤焦油中的钾和钠几乎全部为水溶性的钾盐和钠盐,钙在加氢过程后转变成了更容易溶于水的钙盐,使用该方法可更加准确地评定加氢催化剂和加氢工艺的脱金属效果。

Low temperature coal tar was treated with pure water,and the metals in each extracted phases were quantitatively analyzed by inductively coupled plasma atomic emission spectrometry.Potassium benzoate,2-phenylphenol sodium salt tetrahydrate,calcium naphthenate,iron naphthenate and meso-tetratolylporphyrin-Fe(Ⅲ)chloride were employed as model chemicals to study the metal species in coal tar.The results showed that the splashing problem of oil-water mixture was eliminated,and both inorganic and organic metals could be determined in coal tar.Potassium and sodium in low temperature coal tar were almost watersoluble potassium salt and sodium salt.After hydrogenating,most calcium turned to watersoluble calcium salt.Using this method,the demetallization effect of hydrogenation process can be evaluated more accurately.