湿热水解法测定岩矿中的氯

In this paper, a procedure of pyrohydrolysis-spectrophotometric determination has been estahlished for chlorine in ores and rocks.The catalyst selection and its required quantity,the time and temperature of sample decomposition and the influence of interferring elements and others are also discussed in detail. Because samples are usually fused with alkali, higher blank is an insurmountable problem. However, with our procedure, the above-mentloned drawback can be effectively overcome, and the determination of trace chlorine either in large or in minor quantities of samples also is rather ideal. The determined results indicate that the relative standard deviation in the former is 8.7%, and 4.5% in the latter case. This procedure is simple, rapid and well reproduceable. The detection limit of the method is 10ppm. The results obtained by our procedure are in good agreement with the proposed values from two reference samples in China (DZ∑-1 and DZ∑-2) and one international geochemical reference sample (RGM-1). This method has been proved to be reliable.