采用四苯硼钠溶液电导滴定法确定终点，测定化肥中的钾的含量。测定的适宜的ｐＨ值要大于９，在此范围内氨的存在不干扰测定。测定高含量钾回收率为９９．８％～１００．２％，测定中含量钾回收率为９９．２％～１００．８％，方便简便，测定周期仅需１０ｍｉｎ左右，所需试剂种类和用量少，准确度与四苯硼钾重量法接近。适用于复混肥和钾肥中钾的分析。 Using tetraphenylboron sodium conductivity conductivity titration method to determine the endpoint, the determination of potassium in the fertilizer. The appropriate pH value for the assay is greater than 9, within the range where the presence of ammonia does not interfere with the assay. The determination of high potassium recovery was 99.8% ~ 100.2%, determination of the content of potassium recovery was 99.2% ~ 100.8%, convenient and simple, the determination of the cycle only 10min, the type of reagent needed and use Less amount, accuracy and tetraphenyl boron potassium weight approach. Applies to the analysis of potassium in compound fertilizer and potash.