Synthesis and characterization of modified marine algal biomass using zero-valent iron (ZVI) particle for Cd and Pb removal

The cadmium discharge is one of the most watched issues in an environment and its removal either in waste-stream or environment requires high cost and energy consumption. The adsorption is an applicable process mostly used in any waste-water treatment process to date. The natural biomass offers a candidacy to be converted as environmentally friendly bio-sorbent for cadmium and lead however the study on marine algal biomass modification as biosorbent to remove heavy metals is limited. This study was aimed to synthesize and characterize biosorbent derived from marine algal biomass, Chlorella vulgaris-supported Zero Valent Iron (ZVI). This study was applying a sequence of modification, i.e.: alkali activation using NaOH followed by wet reduction to generate biomass-supported ZVI. Thus, three types of biosorbents were characterized and evaluated to remove Cd and Pb. The characterization of biosorbent was carried out using FTIR and the measurement for both Cd and Pb was conducted using FAAS. The investigation on biosorbent using FTIR exhibited several functional group consisted of mainly hydroxyl, carbonyl and amino. The Chlorella vulgaris-supported ZVI was able to remove 96% of Cd and 97% of Pb, more effective compared to NaOH activation and non-modified biomass.