Preparation and Characterization of Activated Carbon Derived From Waste Materials and Its Application in the Removal of Fluoride from Ground Water

Abstract

Pollution has been a major challenge to environmental engineers today due to the contaminants from natural and anthropogenic origins that are hazardous to human health. Over the last few decades, adsorption has gained importance for purification, separation and recovery process. Among various adsorbents used, activated carbon is well known for its high adsorption capacity due to large surface area and pore volume. Now a days, immense research has been focused towards converting the waste materials into activated carbon, since this technology not only solves the problem of waste disposal but also converts wastes into a valuable product, that can be used as an adsorbent for various treatments. Researchers have studied the production of activated carbon from various materials using physical and chemical processes . However, the adsorption capacity of the activated carbon for a specific adsorbate varies strongly with the type of raw material and the processing techniques used. Muringa pods, Rooster feathers, and Mangosteen Fruits are selected as the precursor for the preparation of activated carbon in the present investigation. Activated carbon was prepared through chemical activation using orthophosphoric acid, zinc chloride, and potassium hydroxide. The effect of various process parameters on porous characteristics of the activated carbon was investigated. Activated Muringa Pod impregnated with OPA shows activated carbon with high adsorptive capacity at an optimised activation temperature of 600 o c, activation time of 2 hours and 60% impregnation ratio of orthophosphoric acid. Adsorption Capacity Decreased in the Order,M 3 > M 1 > M 2. Development of AC was influenced by various factors such as type of chemical reagents used for impregnation, impregnation ratio, carbonization temperature, holding time etc. 7 out of 15 water samples collected from bore wells in Palakkad district exceed the safe permissible limit for fluoride. Experimental results indicated that the prepared activated carbon was suitable for the removal of turbidity, color, total suspended solids and fluoride from ground water.