P. Venu Babu

By Gouri Chaudhuri, Uma Selvaraj, Venu Babu and Richard W. Thilagaraj

Industrial effluents from tanneries and electroplating industries from small‐ and large‐scale sector industrial plants contain substantial amount of toxic heavy metal, which pollutes rivers and lakes, land, air and sea leading to imbalance of ecosystem and certain health issues to humans, animals as well as plants. The worldwide environmental regulations stipulate the reduction of heavy metals in the effluents to permissible levels before discharging into water bodies. Enzyme‐mediated precipitation of heavy metals affords a novel eco‐friendly method for remediation of toxic heavy metals from various industrial effluents like tannery, electroplating and dye industries. This chapter has paid attention to bacterial alkaline phosphatase (BAP) from Escherichia coli C90 and calf‐intestinal alkaline phosphatase (CIAP), which catalyses phospho mono‐ and diesters and produces inorganic phosphate (Pi). The Pi thus generated precipitates the heavy metals as metal‐phosphate complexes. The kinetic behaviour of both the enzymes with para‐nitrophenyl phosphate, ascorbic acid 2‐phosphate and α‐naphthyl phosphate was investigated at various pH regimes from 8 to 11. The chapter also explains in detail the descriptive information on the capability of BAP‐ and CIAP‐mediated precipitation of heavy metals, which is desirable and convenient method for the toxic heavy metals such as chromium, cadmium, nickel and cobalt.

Part of the book: Phosphoric Acid Industry