The Preparation And Performance Of Polystyrene-acrolein-aminothiourea/nanometer Titanium Dioxide Compound As SPE-packing

Solid phase extraction(SPE)is the process of separating and enriching the target by the extraction of trace components in the liquid sample using solid phase adsorbent.SPE has many advantages,such as short operation time,good selectivity and high enrichment times,which has broad application prospects in the field of sample pretreatment.There are many kinds of compound SPE adsorbents,which are mainly used in the extraction of organic and heavy metal ions.At present,the selective separation and enrichment of metal ions have become an important research topic in analytical chemistry.And the adsorption of heavy metals by chelating resin/nano composite SPE filler has become a research hotspot.The research have showed that the polymer / nano composite material with the advantages of the two,so the adsorption capacity of heavy metal ions is better than that of the two materials alone as SPE filler.This technology has great prospects for the development of SPE.Using styrene,methyl acrolein as raw materials,polystyrene-acrolein was synthesized by dispersion polymerization.And then styrene-acrolein-aminothiourea polymer was synthesized by the reaction of polystyrene-acrolein and aminothiourea.Nanometer titanium dioxide was prepared using butyl titanate as raw material.The polymer-nanometer titanium dioxide composite SPE sorbents was prepared by solution co-blending method.The structures and thermal property of the synthesized composite were characterized and analyzed by infrared spectroscopy,scanning electron microscopy,thermogravimetric analyzer,X-ray photoelectron spectroscopy and X-ray diffraction.The adsorption properties of the SPE sorbents for Cr,As,Cd and Pb ions were investigated.The adsorption capacties were 10.42 mg/g,9.64 mg/g and 11.28 mg/g and 12.42 mg/g,respectively.The influence factors on the recovery rate were investigated,such as the type of eluent,the flow rate of the column and the pH value of the solution.The optimal conditions of the mixtures flow rate were 10 mL 5 mol/L nitric acid and 0.3 mL triethanolamine,0.5 mL/min and solution pH of 7.The recoveries of Cr,As,Cd,Pb were 99.80 %,93.23 %,96.36 % and 99.24 % using the self-made SPE column for extracting.And the method showed a good liner relationship(Cr,As,Cd,Pb)in the range of 0.1 to 20 ng/mL.the correlation coefficient of 0.9992,0.9996,0.9995,0.9992,respectively.Finally the method was developed using self-made SPE column coupled with ICP-MS(Pork detection).The limits were 0.046 ug/kg,0.21 ug/kg,0.012 ug/kg and 0.057 ug/kg of Pb,Cd,As and Cr,respectively.The RSD of Pb,Cd,As and Cr were 1.4 %,3.2 %,2.0 % and 1.4 %,respectively.