Application Research Of New Functional Materials For Determination Of Trace Antimony In Water Samples

There are trace antimony elements in environmental water,and a small amount of antimony is toxic to organisms.Organisms using water containing antimony elements for a long time will lead to biological poisoning,so it is necessary to monitor trace antimony elements in environmental water.At present,although the national standard has high sensitivity for the determination of antimony in environmental water,it has low detection limit for trace antimony.Therefore,it is necessary to separate and enrich trace antimony in water samples to improve the content of antimony in the detection solution before the detection of trace heavy metal antimony in environmental water.In this paper,the functional materials prepared in this topic are used for the separation and enrichment of trace antimony in environmental water,and then combined with the instrument to detect the content of trace heavy metal antimony in environmental water.Three kinds of natural plant materials were pretreated and modified by alkaline soaking method and hydrothermal method.Thioglycolic acid,dimercaptosuccinic acid,sodium dimercaptopropanesulfonic acid and polyvinyl alcohol were esterified and flocculated to prepare functional materials.A functional material with better adsorption performance for Sb was optimized by functional material selection experiment,in the eluent screening experiment,a strong Sb eluent and eluent concentration enriched for functional materials were optimized,Experimental evaluation of performance of functional materials by solid phase extraction column.The results are as follows:（1）PH experiment found that alkaline soaking method combined with hydrothermal method in situ doping inorganic modified natural materials prepared functional materials and the functional materials prepared by the flocculation of sulfhydryl compounds and polyvinyl alcohol by ferrous sulfate seven water,and the pretreated peanut shells had good adsorption ability for Sb.Through the amount of adsorption material added experiments,kinetic experiments and isothermal experiments found that after the pretreatment of peanut shell H0,soaking by alkaline potassium permanganate method and hydrothermal method in situ doping modified peanut shell H2 and the glycolic acid and polyvinyl alcohol and ester content after the preparation of composite flocculation 1 to Sb adsorption capacity is more superior to other adsorption materials,Langmui isothermal empirical equation and quasi second-order kinetic equation were satisfied in the adsorption process,and monomolecular layer and chemisorption were the main adsorption processes.The maximum adsorption amounts of H0,H2 and synthetic 1 for Sb were 22.5734μg/mg,40.9836μg/mg and 232.5581μg/mg.However,considering the structural instability of peanut shell,compound 1 was selected as the subsequent experimental material.The optimum adsorption p H for Sb was 6,and the optimum adsorption volume for was 0.02g for 25ml,5μg/ml Sb solution.（2）By eluent screening experiment,H₃PO₄was the best eluent for Sb adsorption of synthetic 1,and the optimum concentration was 10%.In solid phase extraction column When the concentration of H₃PO₄was 10%and the elution flow rate was 1.25m L/min and the Enrichment flow rate was 1.04m L/min.The separation and enrichment performance for of25m L,5μg/ml Sb solution was better by combination of SOLID phase extraction column and flame atomic absorption spectrophotometer,and the average recovery was 97.42%.However,when Hg²⁺,Cu²⁺and Ni²⁺in Sb solution have a high concentration,it can affect the adsorption of Sb,because Hg²⁺,Cu²⁺,Ni²⁺can react with sulfhydryl group to occupy the adsorption site,and interfere the adsorption of Sb in the solid phase extraction column.However,Hg²⁺,Cu²⁺and Ni²⁺in actual environmental water samples are not high.（3）The results of enrichment ratio experiment showed that the recovery rate was greater than 95%for 5m L 1μg/ml Sb solution dilution≤40 when the solid phase extraction column was used in combination with the detection instrument under the optimal conditions,but the recovery rate decreased with the increasing of dilution ratio.The main reason is that the adsorption rate of Sb solution can be directly reduced by the formation of intrinsic flow pores between the functional materials during the continuous enrichment process,and the adsorption ability of Sb solution can be decreased at low concentration In addition,it was found that the reproducibility of synthetic 1 was low,and the experimental error was large when used once again.After separation and enrichment of environmental water samples,the prepared functional materials combined with the detection instrument have higher precision and lower detection limit,and it can be used to detect the content of antimony in environmental water samples below the detection limit of flame atomic absorption spectrophotometer.The result of this method is 0.86μg/L for Actual environmental water sample,which is far lower than the detection limit of antimony by flame atomic absorption spectrophotometer.The method is used to expand the detection range of antimony by flame atomic absorption spectrophotometer and achieve the purpose of accurately monitoring the trace antimony in environmental water.