Novel Method for Preparing Activated Carbons with High Specific Surface Area from Rice Husk

Abstract

This study reports the novel dry activation for preparing activated carbon with a high specific surface area from rice husks using solid NaOH. Materials were characterized by N 2 adsorption, X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. The effects of mass ratio (1−4) and the activation process (dry activation or impregnation) on the surface area were studied, explicating the mechanism of pore development. With a mass ratio of 3, carbons prepared by dry activation possessed a much higher surface area of 2841 m 2 /g than the 933 m 2 /g for impregnation. For the adsorption of phenol, their maximum adsorption capacities were 351.4 and 160.8 mg/g, fitting with the Langmuir model. In addition, the economic analysis estimated a significant gross profit margin of 40.2% for the product. Therefore, it is demonstrated that dry activation is an effective and convenient method for obtaining low cost activated carbon with outstanding surface area.

Review on the physicochemical treatments of rice husk for production of advanced materials

“…On the other hand, extreme conditions accelerated the widening of micropores. Many micropores were destroyed by collapsing or merging into mesopores and macropores, leading to reduction of S BET [295].The most widely used chemical agents include ZnCl 2 , H 3 PO 4 , H 2 SO 4 , KOH and K 2 CO 3 [296][297][298][299][300]. ZnCl 2 and H 3 PO 4 are usually used for activating biomasses which are rich in cellulose, hemicellulose and lignin such as wood and nut shell [301,302].…”

Highly porous activated carbon materials from carbonized biomass with high CO2 capturing capacity

“…Activated porous carbons have been widely used in gas adsorption or gas storage, in electronic devices such as electrodes or capacitors, treatment of pollution in waters [19] and as a catalyst support [20]. Moreover, to improve their properties in energy storage, many researchers tend to use various plants residue such as leaf, sawdust, seaweed and peel [21] as well as plant products such as cellulose, lignin, glucose, xylose [22] and starch to prepare carbonaceous materials with desirable nanostructure and functionalization patterns through hydrothermal carbonization. So far, the studies have been focused on the synthesis of high Preparation of ACs with a high specific surface area and the ability to absorb a large amount of gas from biomass such as lignin [24], corncob [25], fungi [26], chitosan [27], gelatin [28] and starch [29] has also attracted much attention.…”

Preparation of Activated Carbon from Pyrolyzed Rice Husk by Leaching out Ash Content after CO2 Activation

“…This is because of the decrease in the nonparallel single layers and some edge orientation in the CO2 activation (Wang et al 2009). The diffraction patterns of APRKOH and APRK2CO3 show a broad peak at about 24 o , which is ascribed to the overlap of the silica characteristic peak at about 22 o because of the slight silica residue (about 5% as shown in Table 3) and the (002) plane peak at 26 o (Kennedy et al 2004;Song et al 2012). The FTIR spectra of PR, APR, APRKOH, and APRK2CO3 are presented in Fig.…”

“…4. As seen from the patterns of PR and APR, the peak at around 22 o is ascribed to amorphous silica (Song et al 2012). The peak at about 44 o of APR is assigned to the (100) plane, indicating the localized graphitization of the structure (Wang et al 2011).…”

“…The pore size distribution was calculated from the N2 adsorption isotherm, using the BerretJoynerHalenda (BJH) method. The average pore diameter (D) was calculated using the equation: D = 4000V/SBET (Song et al 2012).…”