Physicochemical Analysis and Heavy Metals Remediation of Pharmaceutical Industry Effluent Using Bentonite Clay Modified by H2SO4 and HCl

Abstract

Environmental pollution by industrial effluent has become a vital issue partly because ofthe detection of heavy metals in them, which need to be mitigated. Adsorbents were producedfrom Bentonite clay using 2 M H2SO4 and 2 M HCl as modifying agents in ratio 1:2 by wetimpregnation method. Physicochemical properties of the pharmaceutical effluents such as pH,temperature, turbidity, conductivity, Chemical Oxygen Demand (COD), Biological Oxygen Demand(BOD), and heavy metals were determined. High concentrations of Fe(III) and Zn(II)were observedin the effluents when compared with standards. The optimal value of pH for Fe(III) and Zn(II) was8, and a dose of 0.05 g was found to be the optimal value for all the adsorption system. Theadsorption was best fit to Langmuir isotherm and the pseudo-second-order kinetic model. Theresults obtained in this study showed that the produced adsorbents could be used to supplementthe commercial adsorbents in the specific application. Furthermore, the acid modification washelped to increase the sorption capacity of the clay to the heavy metals studied with H2SO4 beingthe better modification agent.