Title: | Synthesis of high-performance hierarchically porous carbons from rice husk for sorption of phenol in the gas phase |
Address: | "Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology (NUIST), Nanjing 210044, China. Electronic address: shen1225@nuist.edu.cn. Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control (AEMPC), School of Environmental Science and Engineering, Nanjing University of Information Science and Technology (NUIST), Nanjing 210044, China" |
DOI: | 10.1016/j.jenvman.2019.04.012 |
ISSN/ISBN: | 1095-8630 (Electronic) 0301-4797 (Linking) |
Abstract: | "Phenol as a semi-volatile organic compound (SVOC) extensively presents in industrial wastewater. Moreover, it is a main compound of tar existing in the vapor phase from biomass pyrolysis or gasification. So far, most of works on the phenol adsorption by activated carbons have been conducted in the liquid phase. However, the adsorption of phenol in the gas phase has not been reported. This work aims to synthesize the hierarchically porous carbons from the unaltered and pelletized rice husk (RH) via a facile pyrolysis followed by the ball-milling-assisted KOH activation. Herein, the silica nanoparticles in RH acted as a self-template to remarkably increase specific surface areas and pores, thereby giving rise to the formation of hierarchically porous carbons, which showed a relatively high adsorption capacity (maximum value: 1919?ª+mg/g) of phenol in the vapor phase. Generally, the process of phenol adsorption onto porous carbons in the gas phase followed with various interactions, including pore fi lling, electrostatic interaction, hydrophobic effect, and functional groups effect (e.g., pi-pi interaction). And the pseudo-second-order model could well describe the adsorption kinetic. It is noted that the pelletized RH was more favorable to develop the porous carbons with the hierarchically meso-microporous structures that could enhance the transfer of the phenol molecules via the outer layer and subsequent uptake by the adsorption sites on the inner layer. Further, the SVOC phenol was hard to volatilize under ambient conditions due to its relatively higher boiling point (181.7?ª+ degrees C), so the thermal desorption was a potential way to regenerate the spent activated biochars" |
Keywords: | Adsorption *Oryza *Phenol Phenols Porosity KOH activation Porous carbon Rice husk Semi-volatile phenol Sorption; |
Notes: | "MedlineShen, Yafei Zhang, Niyu Fu, Yuhong eng England 2019/04/14 J Environ Manage. 2019 Jul 1; 241:53-58. doi: 10.1016/j.jenvman.2019.04.012. Epub 2019 Apr 11" |