Comparative Study Of Gold Content Determination By ICP-MS,Graphite Furnace Atomic Absorption Spectrometry And Spectrograph

In the gold element quantitative analysis,a variety of instruments and techniques are used in these technologies include: flame atomic absorption spectrometry and graphite furnace atomic absorption spectrometry,inductively coupled plasma atomic emission spectrometry,activation analysis by inductively coupled plasma mass spectrometry,electrochemical method,electrothermal atomic absorption spectrometry,neutron.In geological industry sample analysis,shortening geological field waiting time and improving work efficiency can be more suitable for the analysis of large quantities of samples.This paper compares the spectrograph,graphite furnace atomic absorption and ICP-MS determination of trace gold in gold,nature,national standard materials and a large number of geological samples were determined by graphite furnace atomic absorption spectrograph,and ICP-MS,respectively.The precision and accuracy,and the spectrograph detection limit was 0.38 ng/g,graphite furnace atomic absorption detection limit of 0.26 ng/g ICP-MS,the detection limit was 0.19 ng/g.According to the experimental results,it can be seen that the labor intensity and production efficiency of one meter grating spectrograph are low,but the production cost is low.Graphite furnace atomic absorption and ICP-MS detection of sample pretreatment process is basically the same,are the use of foam plastic adsorption,but the graphite furnace atomic absorption analysis of a sample time for at least two minutes.In case of high content to dilute the sample,sample time will be doubled to extend,not suitable for the rapid analysis of large quantities of samples.ICP-MS as one of the specific requirements and the most sensitive detector elements,the dynamic of wide linear range,low detection limit,matrix interference resistance ability,fast analysis speed,high sensitivity,high efficiency,and improve the former our laboratory by graphite furnace and spectrograph analysis of trace gold,analyzing the defects of slow speed.Although the instrument test method has the advantages of fast and simple,but the actual determination of geological samples and reagents will produce damage to the instrument,therefore,in the use of ICP-MS detection,reduce the reagent to prolong the service life of equipment of instrument injury concern.For the ICP-MS determination of gold in thiourea deposition interference,at this point the determination of national standard material,do comparative experiments,discussedthe feasibility of reducing the thiourea concentration determination of geochemical trace gold in the sample application in the ICP-MS,and the application of this method in many areas such as Baoshan,a large number of samples for the analysis,obtain the data are in line with the standard requirements.