Abstract
Water is the secret of life. The earth is the only planet on which there is life because of water. Therefore water saving should be on the top of our priority. Industries contribute to water pollution hugely with various pollutants varied from large objectives to micro molecules such as heavy metals. Water pollution affects growing plants, animals, human health, and the whole environmental equilibrium thus minimizing water pollution is a critical issue around the world. In this work, we try to evaluate the effectiveness of the metallothionein protein (extracted from soybean debris) after its immobilization on nano-silica (extracted from rice straw) in the lead removal from battery industry wastewater. The prepared nano metallothionein showed the maximum adsorption capacity of about 325 mg/g at pH 3 and for a5 min, incubation time. The nano metallothionein showed high removal efficiency for lead ions from the real battery industry wastewater about 98%. The nano metallothionein not only efficiently removed the lead from the wastewater but also can improve its characters as it can reduce the BOD and COD of the treated water. Besides this high treatment efficiency the prepared nano metallothionein, it can save about 60% of its activity after 50 reuse cycles. The prepared nano metallothionein can be effective cheap adsorbent for lead ions removal from wastewater. A large-scale study for the use of the prepared nano metallothionein as a filter in the wastewater pipes of battery factories.
•Lead ions is one of the most dangerous water pollutants.•Metalloethionein is a cystein rich protein.•Nano silica is an excellent immobilization support.•Nano metallothionein is effective in adsorption of lead ions from battery industry waste water.