Abstract

Adsorption capability of Sponge Iron Plant (SIP) waste was explored using Zn metal solution. Surface modification of sponge iron plant (SIP) waste was achieved by impregnation with dilute HCl which resulted in improvement of BET surface area by 29%. This surface modification is further authenticated by FTIR and SEM study. Influence of various parameters such as pH, Temperature, Initial Zn Concentration and Adsorbent Dosage on adsorption process was studied. A 24 full factorial design of experiments (DOE) was used to ascertain the significance of each factor and their mutual interactions on the adsorption process. The two levels of pH, Initial metal Concentration, Temperature and Adsorbent Dosage considered were 6 & 8, 20ppm &100ppm, 30oC & 40oC and 0.5g/L & 1.5g/L respectively. All the main effects were found to be statistically significant while none of their interactions showed any significance. The difference between the average of combinations and the average of center points was found to be 2.75% showing there was no significant curvature present. Among all the parameters pH was found to be most significant parameter while Adsorbent dosage was least affected. The experimental data were fitted to various isotherm models. Maximum adsorption capacity 128.20 mg/g was observed using Langmuir model at pH 8 and temperature 30◦C. The sorption reaction fitted well to a pseudo second-order rate model.