阳离子褐煤树脂的阳离子度测定方法研究

采用四苯硼钠电位滴定法测定阳离子褐煤树脂的阳离子度.通过消除测定方法的离子干扰、优化四苯硼钠电位滴定法的测定条件来提高测定方法的准确度.采用5％盐酸溶液提取阳离子腐植酸,去除钾离子和其他水溶性杂质;四苯硼钠电位滴定过程中,提纯后阳离子腐植酸加入量为0.5g,用0.2％氢氧化钠溶液溶解阳离子腐植酸,在pH 10.0条件下,选用甘汞电极为参比电极,氟硼酸根离子选择性电极为指示电极,用十六烷基三甲基溴化铵标准溶液电位滴定四苯硼钠,电位突变约200 ～300 mV,加标回收率达95％,满足分析测试的要求.实验结果表明,该方法选择性好、准确性高、易于操作,具有较高的推广应用价值.

Cationic Degree Determination of Cationic Lignite

The method of determining cationic degree of cationic lignite is tetraphenylboron sodium potentiometric method.By eliminating the ion disruption,optimizing the determination conditions of tetraphenylboron sodium potentiometric method,the two aspects improve the accuracy of the determination method of sodium.The results show that the cationic humic acid are extracted with 5％ hydrochloric acid solution in order to remove the potassium and other soluble impurities.In the process of tetraphenylboron sodium potentiometric method,the purification of the cation humic acid added amount is 0.5 g,with 0.2％ sodium hydroxide solution of cationic humic acid,in alkaline conditions pH 10.0,selects the calomel is reference calomel,fluoboric acid root ion selective electrodes is indicating electrode,with hexadecyltrimethyl ammonium bromide standard solution potentiometric titration,tetraphenylboron sodium.The potential mutation is 200 ～ 300 mV.The standard addition recovery rate reaches 95％ which can satisfy the analytical.The detecting results are verified and calculated by laboratory test which shows that the sodium tetraphenylborate method can satisfy the demand of product purchasing,checking and quality supervision with good reproducibility and high degree of accuracy.