硫酸根含量是水质评价指标之一。水样中测定硫酸根的比浊法是用甘油作稳定剂,生成硫酸钡晶形沉淀,晶粒较大,沉淀速度快,因此比浊时要定频定时搅拌不易掌握,精密度和灵敏度均较低。本文应用明胶作硫酸钡沉淀的分散稳定剂,使硫酸钡能较均匀地分散在明胶溶液中,测定时勿需搅拌,大大地减缓了沉淀的速度,灵敏度也比原法提高1.5倍左右。试验证明:在0.001—0.01N盐酸介质中,有明胶存在时, Sulfate content is one of the water quality evaluation indicators. Turbidimetric determination of water samples is the use of glycerol as a stabilizer to produce barium sulfate crystal precipitate, larger grains, precipitation speed, so the turbid time to fixed frequency mixing is not easy to grasp, the precision and sensitivity are more low. In this paper, gelatin as barium sulfate precipitation stabilizer, so that barium sulfate can be more evenly dispersed in the gelatin solution, the determination without stirring, greatly slowed down the precipitation rate, the sensitivity is also increased by 1.5 times than the original method. Test proved: in 0.001-0.01N hydrochloric acid medium, the presence of gelatin,