Study And Application Gypsum Samples Testing By ICP-AES And ICP-MS

Gypsum is kind of mineral with monoclinic crystal system and its main ingredient is Ca SO4.China is rich in gypsum mineral resources and has been widely applied in many fields. The composition of the geological sample gypsum is very complex and has lower purity of gypsum, and its status is often like complex(mixed) deposits. Currently, the national standard of " Chemical Analysis Methods of Gypsum"(GB / T 5484-2012) is China Building Materials Academy which is amended according to the characteristics of China’s commodity gypsum varieties on the basis of GB / T 5484-2000, and it is mainly applicable to the commodity gypsum. Since the composition of the geological sample gypsum is very complex and has generally lower purity of gypsum, it is quite important for the geological testing staff to built the multi-element analysis methods by using ICP and ICP-MS to analyze the gypsum samples accurately and rapidly analysis methods, however, the current existing the analytic method of gypsum samples(GB / T 5484-2012 chemical analysis methods of gypsum) did not make the supporting testing methods for large instruments like ICP and ICP-MS. They still remained in the traditional volumetric method, gravimetric method, spectrophotometry, atomic absorption spectrometry method which have long process, slow speed and are difficult to control. The above methods are not adaptable to the contemporary requirements of high-volume, multi-element, low detection limit, low cost and the rapid determination of the geochemical gypsum samples. In particular, it is particular difficult to test the micro-elements such as Li, Be, Nb, Ta, Cs, Cr,Mn,Zn,V in the sample accurately through the above methods.These problems are currently the bottleneck problem for the testing of the geological gypsum samples and also the difficulties in testing. According to the current existing problems of the testing for the main and minor elements of the geological gypsum, in this method, it does the innovative research as the following based on the previous research work people have done:1.Established the ICP-AES which can do the successive testing for testing the main elements such as Ca,Mg,S,Fe,K, Na, AI,Ti and Sr in the gypsum samples in the same liquor. Comparing with the typical volumetric method of testing Ca and Mg and the gravimetric method, it is faster and more adaptable to the mass testing of the geological samples. Comparing with the atomic absorption determination of K, Na, AI,Ti and Sr, it is faster, more accurate and with lower detection limitation.2. Established the ICP-MS which can do the successive testing for the micro-element like Li, Be, Nb, Ta, Cs, Cr,Mn,Zn,V of the gypsum samples in the same liquor. Comparing with the typical methods like atomic absorption and spectrophotometric method, it is faster, more accurate,with lower detection limitation and stronger anti-interference.3. The study identified the decomposed condition of the geological gypsum samples, the drawing of working curve of the ICP-AES, ICP-MS determination of gypsum samples, elimination of matrix effects, correction of interference and selection of the internal standard element, and improve the ICP-AES, ICP-MS determination method of the geological gypsum samples.The operating method of testing the main and minor elements of the established ICP-AES and ICP-MS determination of gypsum samples in this method is easy to operate, is with low costs,can test rapidly, and have high accuracy and precision, and good technical indicators of the detection limit. The measured value and the standard value are basically matched according to the verification by the National primary standard substance standard. It can meet the requirements of the DZ / T 0130-2006 "The Specification of Testing Quality Management for Geological Laboratories" and can be applied to test the geological gypsum samples.