RESUMO
Objective To simplify the detection method of sulfate in the water purifying agent poly aluminium chloride.Meth ods Poly aluminium chloride solution was filtered using filterable film and Tween liquor was added to the filtered so lu tion to in crease its stability,then the sulfate content in the solution was determined by barium sulfate turbidimetry.Results The se-lected analytic wave-length of the method was720nm and it showed a good linear relationship with r=0.9991.The coefficient of varia tion and recovery rate were2.7%～3.4%and92.0%～103.2%respectively,which revealed no significant differences com-pared with the results obtained using the national standard determination method,the weight method.Conclusion The method was rapid and easy to operate,which was suitable for determination of batch samples.