Abstract: Ever rising demands of electric and electronic appliances in the era of urbanization has increased the production of e-waste and menacing aqueous metallic wastes world-wide. The aqueous metallic waste contains high level of lethal ionic metals and compounds which need to be reduced to a level as suggested by various standards. In presented work; process of adsorptive removal of heavy metals mainly; Cr(VI), Cu(II) and As(III) by Husk of Cajanus Cajan (HCC) biosorbent; is used. To analyze the adsorptive efficiency of the HCC a batch mode experiment was conducted with the process parameters; pH of the solution (pH0 = 1.0–7.0), Adsorbent Dose (AD = 0.1-0.7mg/50ml), Initial Metal Ion Concentration (IMC = 1–30 gm/L) and Temperature (Temp = 295-325 K). The results obtained through laboratory experimental setup were analyzed and it was observed that the removal of Cr(VI) is maximum in acidic pH range (pH0=1), while the removal of Cu(II) and As(III) is maximum at neutral or near to neutral pH range (pH0=6.0-7.0). The maximum removal of Cr(VI), Cu(II) and As(III) from the aqueous solution was done at high adsorbent dose (AD=0.7 gm/50 ml). The analysis also reveals that the pH of the solution is the most significant factor among all the experimental factors. To validate the obtained experimental results rules were induced using decision tree method and a Fuzzy Inference System (FIS) was designed and trained on the basis of rules thus obtained. Inferences given by the FIS, when applied on the same data, shows close accordance to the experimental results which validates the results and inferences obtained from laboratory experiments.
Keywords: Adsorpiton, FIS, Heavy metals, HCC.