production of activated carbon from oil palm empty

Twelfth International Water Technology Conference, IWTC12 2008, Alexandria, Egypt

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PRODUCTION OF ACTIVATED CARBON FROM OIL PALM EMPTY FRUIT BUNCHES FOR REMOVAL OF ZINC Md. Zahangir Alam *, Suleyman A Muyibi and Noraini Kamaldin Bioenvironmental Engineering Research Unit (BERU), Department of Biotechnology Engineering, Faculty of Engineering, International Islamic University Malaysia (IIUM), Jalan Gombak, 53100 Kuala Lumpur, Malaysia *Correspondance: E-mail: [email protected]

ABSTRACT Activated carbons derived from oil palm empty fruit bunches (EFB) were investigated to find the suitability of its application for removal of heavy metal (Zinc) through adsorption process. The thermal activation at 500, 750 and 1000°C for 15, 30 and 45 minutes was used for the production of activated carbons. The statistical analysis and batch adsorption test were done to optimize the activation conditions for activated carbon production. The results indicated that activated carbon derived from 1000°C and 30 minutes has maximum adsorption capacity (1.63 mg/g) for the removal of zinc (98%) in the aqueous solutions. The characterization of ACs produced was measured to evaluate its high quality. Keywords: Activated carbon, oil palm empty fruit bunches, adsorption, zinc

INTRODUCTION Heavy metals are common in industrial applications such as in the manufactures of pesticides, batteries, alloys, electroplated metal parts, textile dyes, steel etc (Kvech and Tull, 2005). Heavy metals become toxic when they are not metabolized by the body and accumulate in the soft tissues. Heavy metals may enter the human body through food, water, air, or absorption through the skin when they are exposed to humans in agricultures, manufacturing, pharmaceutical, industrial, or residential settings (Lenntech, 1998). Heavy metal toxicity can result in damaged or reduced mental and central nervous function, lower energy levels, and damage to blood composition, lungs, kidneys, liver, and other vital organs (International Occupational Safety and Health Information Centre, 1999). Therefore, the removal of heavy metals from wastewater is necessary before safely discharged. The main objective of water treatment is to produce high quality water that is safe for human consumption, has aesthetic appeal, conforms to state and federal standards and economical for production. One of the tools that help to achieve these goals is by using activated carbon (Kvech and Tull, 2005).

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Various treatment technologies have been developed for the purification of water and wastewater contaminated by heavy metals. The most commonly used methods for removal of metal ions from industrial effluents include chemical precipitation, solvent extraction, oxidation reduction, dialysis/electro dialysis, electrolyte extraction, reverse osmosis, ion exchange, evaporation, cementation, dilution, adsorption, filtration etc. Among these, adsorption has evolved as the front line of defense especially those could not been removes by other techniques (Mohan and Singh, 2001). One of the methods of adsorption is by using activated carbon. A variety of activated carbon available commercially but a few of them is selective for heavy metals removal and very costly. Besides, a large quantity is required for treatment of large area. Thus, utilizing economically feasible method is the solution for the problems. Activated carbon includes a wide range of amorphous carbon-based materials prepared to exhibit a high degree of porosity and an extended inter-particulate surface area (Kvech and Tull, 2005). These qualities impart activated carbon with excellent adsorbent characteristics that make carbon very useful for a wide variety of processes including filtration, purification, deodorization, decolorization, purification, and separation. Activated carbons have been produced from a large number of carbonaceous raw materials such as coal, lignite, wood, coconut shell, and some agricultural waste products (Guo and Lua, 1998). The effectiveness of activated carbon as an adsorbent attributed to its unique properties, including large surface area, a high degree of surface reactivity, universal adsorption effect, and favorable pore size (Kvech and Tull, 2005). Malaysia is the largest palm oil producer in the world. This industry creates almost 14 million tonnes oil palm empty fruit bunches (EFB) per year (Suhaimi and Ong, 2001). This wastes product can be use as renewable resources to reduce the environmental problems such as disposal and burning of biomass. EFB proposed as raw material for activated carbon production due to its high carbon content. Conversion of EFB to value-added product such as activated carbon would directly solve part of the environmental problems while utilizing abundant and cheap biomass. Therefore the activation conditions were optimized to produce high quality of activated carbon for the effective removal of zinc in aqueous solution.

MATERIALS AND METHODS Sample collection and preparation for activated carbon Oil palm empty fruit bunches (EFB) as the raw material for the production of activated carbon was collected from Oil Palm Industry, Dengkil, Malaysia. The raw material EFB was washed several times using tap water and finally with distilled water. The EFB sample dried at 105°C for 24 hour in oven to remove excess water content until constant weight. Then, the dried sample was grinded to size of 0.5 mm and stored at room temperature for further use.


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Production of activated carbon by thermal activation using statistical approach For thermal (heat) activation, the initial weigh of grinded EFB was measured and placed in crucible with covered and heated in a furnace at different temperatures and times according to the design of experiment for its optimization (Alam et al. 2007). Then, the samples (activated carbon produced) were crushed and sieved using sieve shaker to size fractions less than