Research On Rapid Detection Of Heavy Metals In Water Based On X-ray Fluorescence Analysis Of Functional Solid Phase Extraction Membranes

With the development of industrial production and urban modernization in recent years,a large amount of wastewater has been discharged,the accumulation of heavy metals in water sources has intensified,and heavy metal pollution has become more serious.For the detection of heavy metal-containing wastewater,especially the determination of trace and trace heavy metals,instrumental analysis methods such as atomic fluorescence spectroscopy,ICP-OES,and ICP-MS can be used.The use of these methods to measure heavy metals requires on-site sampling and return to the laboratory.Testing is complicated and takes a long time.In this study,for the on-site detection of trace heavy metals in water,an X-ray fluorescence analysis(XRF)method based on a functionalized solid-phase extraction membrane was developed to study a rapid detection and analysis method for heavy metals in water.First,through chemical modification,sulfonic acid groups were introduced on the surface of viscose fibers to prepare a heavy metal adsorption material,sulfonated viscose fibers.During static adsorption,the total adsorption capacity for mixed heavy metals of Co,Ni,Cu,Zn,Cd,and Pb can reach 8.9 mg/g;during dynamic filtration,the sulfonated viscose fiber membrane can achieve Co and Ni at ppb concentration levels in water,Cu,Zn,Cd,Pb are completely enriched.Then,a specific standard curve for the detection of heavy metals in sulfonated viscose fiber membranes by a portable X-ray fluorescence spectrometer was established,and the rapid detection of heavy metal enrichment on the membrane was achieved.Based on the rapid detection of p XRF for the enrichment of heavy metals on the membrane surface,a set of detection and analysis methods have been established,which can achieve rapid detection of trace Co,Ni,Cu,Zn,Cd,and Pb elements in water.The solid-phase extraction membrane-based analysis method was used to compare the calibration values of a large number of simulated water samples and heavy metals in water samples.The two showed a high correlation with a relative error of 1.4%.The analysis of Co and Cd element content in actual water samples showed that the relative error between the test results and the ICP-MS test results was as low as 9.7%.For repeated detection and analysis of the same water sample,when the initial concentration of the element to be measured is greater than 20 ?g/L(Co,Ni,Cu,Zn)or greater than 40 ?g/L(Cd,Pb),the relative standard deviation of the test results RSD <20%.According to the analysis of its detection performance,this method is considered to be a simple,fast and accurate method for the detection of trace heavy metals.It can be used as an alternative detection method for large-scale analytical instruments and has high practical application value.