REMOVAL OF LEAD FROM POLLUTED WATER BY USING CLAY MINERALS

Document Type : Original Article

Authors

1 Soils and Water Use Dept., Nat. Res. Cent., Cairo, Egypt

2 Soil Dept., Fac. Agric. Benha Univ., Egypt

Abstract

Clay minerals or natural materials such as zeolite play an important role in reducing the potential hazards of toxic elements. They cannot completely destroy heavy metals but can only be transformed from a single phase oxidation or organic compound to another. In this study clay minerals used to reduce the hazardous of lead on aqueous solutions. The used minerals were zeolite, bentonite and montmorillonite. Each mineral was applied at the rates of 1, 3 and 5% (W/V) of waste water. The concentrations used of lead were 60, 120 and 180ppm. The results observed that wherever increased the rate of the clay minerals added to the contaminated liquid has increased the amount adsorbed of lead. Therefore, the highest amount adsorbed of lead was obtained with 5% of soil minerals in all cases. The highest amount of lead adsorbed was obtained with zeolite at the rate of 5% (177 ppm) followed by montmorillonite and bentonite (165 and 145 ppm), respectively. There is a positive relationship with both the amount adsorbed of lead and the rate of soil mineral added to the solution of contaminated. On the other hand, the highest lead removal efficiency was found as about 98.7% with the rate of 5% zeolite mineral. Whereas, the lowest lead removal efficiency was found as about 39% with the rate of 1% bentonite mineral. The arrangement of the soil minerals ability to adsorb lead was followed this order: zeolite <  montmorillonite < bentonite. This study suggests that using of available natural materials could be an economic and promising alternative solution in contaminated water to minimize hazards of heavy metals. The clay minerals are suitable materials for heavy metal removal from the industrial waste water.

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