Thermal and ion-exchange studies of 4-aminosalicylic acid-oxamide- formaldehyde-II copolymer resinAuthor(s): Mangesh S.Dhore, Suraj S.Butoliya, Anil B.Zade
Copolymer resin 4-ASAOF-IIwas synthesized bythe condensation of 4-Aminosalicylic acid (4-ASA) andOxamide (O)with Formaldehyde (F) in the presence of hydrochloric acid catalyst with 2:1:3 molar ratios of reactingmonomers.The structure of the resinwas characterized by various spectral techniques like infra-red (FTIR) and nuclearmagnetic resonance (1H and13C-NMR) spectroscopy. The empirical formula andempiricalweight of the resinwere determined byelemental analysis.Themorphological featureof the 4-ASAOF-II copolymer resin was established by Scanning electronmicroscopy(SEM). Thermal study of the resinwas carried out to determine itsmode of INTRODUCTION Ion-exchange has beenwidely used to treat heavy metal-containingwastewater andmost of the ion-exchangers currentlybeing used are commerciallymassproduced organic resins.Analysis of trace elements presents as complexmixtures in natural andwastewater, andinbiological, industrial, andgeological samples, are a challenging problemin analytical chemistry.The rapid development of electronic instrumentation has created powerful analytical tools but these can give erroneous results because of the presence ofmatrix elements. To obtain reliable data, the best course is to separate the analytes of interest fromthematrix constituents and to determine themin the isolated state. Thus, preconcentration and separation bybatch equilibration ismandatory, particularlywhen analytes are present at trace levels[1,2] Ion-exchangers arewidely used for the treatment of radioactivewastes fromnuclear power stations[3,4]. decomposition and relative thermal stability.TheFriedman andChangemethods have been usedin the present investigationtocalculatethermal activationenergy(Ea), order of reaction (n) and frequency factor (z). The chelatingion-exchange propertyof this copolymerwas studied for eightmetal ions viz. Fe3+,Cu2+,Ni2+,Co2+, Hg2+, Zn2+, Cd2+ and Pb2+ ions by using batch equilibriummethod. The chelating ion-exchange studywas carried out over awide pHrange at different time intervalsusingdifferent electrolyteofvarious ionicstrengths.