离子色谱法评价电解条件对电解法合成四甲基氢氧化磷时阴极液中Br^-含量的影响

Evaluation of Effect of Electrolytic Conditions on Content of Br^- in Catholyte Solution of Electrolysis Synthesis of Tetramethyl Phosphorus Hydroxide by Ion Chromatography

采用离子色谱法测定以四甲基溴化磷为原料电解法合成四甲基氢氧化磷的阴极液中的痕量Br^-,色谱工作条件为:IonPac AS11-HC分离柱,柱温30℃,淋洗液为30mmol·L^(-1) KOH溶液,淋洗液流量1.0 mL·min^(-1),抑制器电流75 mA。Br^-的线性范围为1.00~10.00 mg·L^(-1),检出限(3s/k)为0.028 5mg·L^(-1)。加标回收率在96.2%~111%之间,测定值的相对标准偏差(n=7)小于1.0%。考察了不同商业化隔膜、电解时间、电流密度等电解条件对阴极液中Br^-含量的影响,结果表明:以JCM-Ⅱ均相阳离子交换膜分隔电解槽阴、阳极室时,当电流密度为60mA·cm^(-2)、通电量为理论电量的60%时,阴极液中Br^-含量较低。

Ion chromatography was applied to the determination of trace Br- in catholyte solution of electrolysis synthesis of tetramethyl phosphorus hydroxide from tetramethyl phosphorus bromide. The chromatography work conditons were as follow：IonPac AS11-HC separation column, clolumn temperature of 30℃, 30 mmol·L^-1 KOH solution as eluent,flow rate of 1.0 mL·min^-1, suppressor current of 75 mA. The linearity range of Br- was 1.00-10.00 mg·L^-1, with detection limit （3s/k） of 0.028 5 mg·L^-1. Values of recovery obtained by standard addition method were in the range of 96.2%-111%, RSD （n=7） was less than 1.0%. The effects of different commercial membranes, electrolytic time, current density on Br- content in catholyte solution were investigated. The results showed that, when JCM-Ⅱ homogeneous cation exchange membrane was used to separate the anode and cathode of the electrolytic cell, the current density was 60 mA·cm^-2 and the power was 60% of the theoretical power, Br- content in the cathode solution was less.