Research On Arsenic Multiphase Interface Migration Process And Speciation Analysis

Arsenic is a toxic metalloid element which is widely distributed in theatmosphere, water, soil, rocks and organisms. There are a variety of valence states inthe natural environment. Toxicity of arsenic in the natural environment is relevant totheir presence in form, precise information on the toxicological properties of arseniccould not be obtained by determination of total arsenic content of the sample, which isnot conductive to the study of harm of arsenic to environment and human life.An online arsenic speciation analysis system which is fast, stable, sensitive andaccurate was established by using high performance liquid chromatography-hydridegeneration-atomic fluorescence spectrometry. The form and content of arsenic insaliva of workers in coking plant, nearby residents, four healthy volunteers before andafter ingesting seaweed and Chinese medicine were measured using this system. Thecontent of human exposure to arsenic is reflected through arsenic speciation in saliva.A method of analyzing arsenic forms in food seasoning (soy sauce and vinegar),dairy products and saliva samples online by using cold trap-gas chromatography-hydride generation-atomic fluorescence spectrometry was established. The influenceof the kind and concentration of the acid medium, the concentration of KBH4, thereaction time of hydride generation device, flow rate of carrier gas and otherexperimental conditions were studied. Compared with liquid chromatography method,this method is faster, more stable and without any pre-treatment.An online analysis system consist cold trap-gas chromatography-hydridegeneration-atomic fluorescence spectrometry was first established and differentforms of arsenic hydride can be determined. A modified zirconia materials wasprepared using surface-modified zirconia particles as load and activated carbon(AC)as carrier, their morphology and structure were characterized by using microscopy(TEM), X-ray diffraction, scanning electron microscopy (SEM)(XRD), etc.Adsorption column made by the modified materials were attached to the aboveanalysis device. The influence of adsorption capacity of the modified materials, thetype and concentration of the acid medium, the concentration of KBH4, the flow rateand temperature of Ar, the flow rate of He and other factors to adsorption capacitywere analyzed. The adsorbent material that reached saturated adsorption capacity were recovered by eluting the line, the recovery rate is AsⅤ99.18%、 MMAⅤ84.25%%.