Preparation Of New Meterials For The Adsorption Of Heavy Metal Ions From Aqueous Solutions

Environmental pollution caused by heavy metal ions is deteriorating the inhabitedenvironment and endangers the human health, which has become a serious problem dueto their toxic properties and the tendency for bio-accumulation in the food chain. Thedetermination of ultra trace of heavy metals in environmental samples plays animportant role in the environmental pollution monitoring. Despite the selectivity andsensitivity of modern analytical techniques, there is a crucial need for thepreconcentration of trace elements before their analysis. Among the several differenttypes of methods, the adsorption process using adequate adsorbents is considered as oneof the most efficient and economical techniques in the viewpoint of simple design andfacile handling. In this study, several new adsorption materials are synthesized in orderto pre-concentrate and separate trace heavy metal ions. The influence of experimentalconditions, pH value, and contact time on the sorption behavior is investigated. Theadsorption isotherm, kinetics, and thermodynamics have also been studied. The detailednovelties of this research can be categorized as following:1. The adsorption of Cd(â…¡), Zn(â…¡), and Cu(â…¡) from chloride medium with PTFESelective Resin containing primary amine N1923and Cyanex923has beeninvestigated. The influence of the pH of solution and the contact time on theadsorption has been discussed. The adsorption isotherm and kinetics have also beenstudied.2. The poly(aryl ether ketone) containing pendant carboxyl groups (PEK-L) is preparedto develop efficient adsorbent for heavy metal ions, Cu(â…¡), Pb(â…¡), Co(â…¡), Ni(â…¡),and Cd(â…¡), from aqueous solution. The influence of experimental conditions, pH value, and contact time on the sorption behavior is investigated. The adsorptionisotherm, kinetics, and thermodynamics have also been studied.3. An on-line separation/preconcentation of Cu(â…¡), Zn(â…¡), Mn(â…¡) and Pb(â…¡) usingmicrocolumn packed with oxidized MWCNTs prior to their determination by FAAShas been studied. Several variables relevant to the retention and elution, such assample loading time, sample flow rate, sample pH, eluent concentration, and eluentflow rate have been investigated and optimized. In addition, the proposed procedurehas been successfully applied to the determination of trace Cu(â…¡), Zn(â…¡), Mn(â…¡),and Pb(â…¡) in vegetable samples.4. Titanium dioxide/multi-walled carbon nanotubes (TiO2/MWCNTs) nanocompositeshave been synthesized, characterized, and used for the adsorption of Pb(â…¡) fromaqueous solution. The pH effect, kinetic study, adsorption isotherm andthermodynamic study are examined in batch experiments.5. The graphene-zinc oxide composites (G-ZnO) are prepared and used for theadsorption of Cu(â…¡), Pb(â…¡), and Cr(â…¡I) from aqueous solutions. Effects of pH andcontact time, kinetics, adsorption isotherms, and thermodynamics are examined inbatch experiments.