Application Studies Of Activated Carbon Derived From Rice Husks

Recently, much attention has been focused on the use of plant biomass to produce functional carbonaceous materials, encompassing economic, environmental and social issues. Rice husk is a by-product of rice processing. The production of functional activated carbon materials starting from cheap natural precursors using environmentally friendly processes is a highly attractive subject in material chemistry today. The annual world rice production is about 571 million tonnes resulting in approximately 140 million tonnes of rice husk available annually for utilization,96% of which are generated in the developing countries. The major constituents of rice husk are cellulose, hemicellulose, lignin, and mineral components. The content of each of them depends on rice variety, climatic conditions, and even the geographic localization of the culture. Rice husks are usually used as a low-value energy resource, burned in the field, or discarded, which are unfavorable to environment. The processing and transformation of rice husks into activated carbon with good adsorption properties would alleviate problems of disposal and management of these waste by-products, while producing value added products from rice husks for water and wastewater treatment, etc., to expand the carbon market. In our previous studies, activated carbons were prepared from rice husks by chemical activation with KOH, NaOH, Na2CO3 and K2CO3 at different temperatures for various times. The previous researches have demonstrated the ability of rice husk-based activated carbon for many metal ions and organic molecules from aqueous phase adsorption. They were also used as electrode materials for batteries and capacitors.Within the above scope, this study is devoted to the following aspects:(â… ) In this paper, we prepared porous carbon with good adsorptive capacity from rice husks by activation of KOH and NaOH at lower temperatures, and studying the mechanism activation process.The effects of washing temperature on the properties of the porous carbon were studied, and the mechanism and the difference between KOH and NaOH were investigated. (â…¡) We studied the rice husk based porous carbon and Commercial grade porous carbon adsorbed formaldehyde by serious of physiochemical measurements. (â…¢) The objective of this section is to evaluate the hydrogen storage capacity the hydrogen storage capacity of two types of activated carbons was analyzed hydrogen adsorption isotherms at 298 K and up to 60 atm. Target values that can be achieved for the critical parameters in such a system have been drawn up by the US Department of Energy at room temperature and atmospheric pressure. (â…£) We studied the performance of electrical double layer capacitors with porous carbons derived from rice husk. Different activation conditions can affect the pore structure of the carbons. This paper supplied a method of the utility of rice husk in environment, cell, energy sources, char adsorption and chemical modified electrode and studied the characterization of high surface area porous carbon.The paper (i) presents a critical analysis of rice husks and describes their characteristics, advantages and limitations; (ii) introduces the preparation of porous carbon from rice husks and (iii) discusses various applications involved.In conclusion, a new method was proposed for the comprehensive utilization of bio-resources like rice hull. Many good achievements with important social and economic significance were obtained. In this review, an extensive list of rice husks literature has been compiled. Conclusions have been drawn from the literature reviewed, and suggestions for future research are proposed.