Performance of Tire Powder for Absorption of Lead, Zinc and Manganese Heavy Metals and Determination of Kinetic and Adsorption Isotherms

Abstract

The limitation of fresh water resources in the most parts of the country has necessitated the use of unconventional water resources. Wastewater is one of these unconventional sources, however the environmental impacts of wastewater reuse should be carfully considered. The present study aimed to examine the effect of the rubber powder to absorb the heavy metals of lead, zinc and manganese in laboratory scale. The batch tests to evaluate the absorption equilibrium time were conducted in constant pH of 5.5 and the soluble metal concentration equal to 100 mg per liter. The adsorption kinetic results showed, the removal efficiency of lead, zinc and manganese were 67.2, 74.3 and 39.9 percent, respectively. Time to reach equilibrium for zinc and manganese were 180 and 120 minutes, respectively. But lead does not reach equilibrium during the 180 minutes of testing time. Also, the adsorption isotherms tests were performed for these metals and the data were fitted with the linear, Langmuir and Freundlich models. The results showed that the Freundlich adsorption model with regression coefficient equal to 99 percent was the best compliance with the laboratory results.

Keywords

• key words: unconventional water
• heavy metals
• tire powder
• batch absorption tests
• adsorption kinetic
• adsorption isotherms