Due to the high quantities of water used in the dyeing processes, textile industry has become one of the greatest sources of liquid effluent that contaminated with various kinds of dyes. The liquid effluent may cause serious water pollution problems and it requires solutions.However, commercially available activated carbons are still considered expensive due to the use of non-renewable and relatively expensive starting material such as bituminous coal. Therefore, this study investigates the potential use of tropical fruit wastes such as mangosteen (Garcinia mangostana L.) peel and rambutan (Nephelium lappaceum L.) peel that available in Malaysia, as the precursor for the preparation of activated carbon which can be applied for the removal of basic Malachite Green and reactive Remazol Brilliant Blue R dyes from aqueous solution. Optimum activated carbon preparation conditions were determined using response surface methodology. The activated carbons prepared were characterized to study their respective physical and chemical characteristics. Isotherms, kinetics and thermodynamics for adsorption of basic and reactive dyes were investigated by batch adsorption test.

The management of solid waste continues to be a leading challenge in developing country like Malaysia. Rapid urbanization and industrialization has changed the characteristics of solid waste generated. Typically, leachate represents the water which passes through the waste from precipitation from the waste within the landfill site, resulting in a liquid containing suspended solid and soluble components of the waste from the degradation of the waste by macro-organisms. In common observation, leachate migrates through the pores available within the mass and drains away in drainage layer. To date, knowledge on the development and use of activated carbon from fruit waste such as durian peel for leachate treatment has not been established and documented yet. Therefore, the ability of durian peel-based activated carbon was tested for the removal of COD and colour from semi-aerobic landfill leachate by adsorption process. Optimum variable conditions were determined using response surface method. The removal pattern of the leachate were investigated by batch adsorption test. Isotherm and kinetic model were employed to determine the adsorption characteristic of the prepared sample.