Volume 13, No. 6, December 2013, Pages 1779-1789 PDF(1.18 MB)
Development of Porous Template Carbons from Montmorillonite Clays and Evaluation of Their Toluene Adsorption Behaviors
Zeng-Yei Hseu1, Hsing-Cheng Hsi2, Jhih-Siang Syu3, Li-Chun Wang4
1 Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, 1, Shuefu Rd., Neipu, Pingtung 91201, Taiwan
2 Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan, 71 Chou-Shan Rd., Taipei 106, Taiwan
3 Department of Safety, Health and Environmental Engineering, National Kaohsiung First University of Science and Technology, No.2, Jhuoyue Rd., Nanzih, Kaohsiung 811, Taiwan
4 Chemical Systems Research Division, Chung-Shan Institute of Science and Technology, 481, Sec. Chia An, Zhongzheng Rd., Longtan Shiang, Taoyuan 325, Taiwan
Carbon replicas were developed with two montmorillonites as the template and sucrose as the carbon source. The fabrication procedures included sucrose doping, polymerization with H2SO4, carbonization at 500–900°C, and liberation of carbon replicas from the template skeleton. N2 adsorption isotherms indicated the all of the resulting carbon replicas contained both micropores and mesopores. A higher carbonization temperature typically led to greater initial N2 adsorption, suggesting the presence of a greater number of micropores. Since no measurable micropores were found in the parent montmorillonites, those observed in the carbon replicas may have developed via activation of inherent water due to dehydration of montmorillonite clay or sucrose during the high temperature carbonization. XRD examination confirmed the formation of both graphite-like structure and amorphous carbon. The C content, C/H molar ratio, and the extent of π-electron resonance of the carbon replicas increased as the carbonization temperature rose, indicating that a higher temperature caused more thorough carbonization in the montmorillonite templates. Toluene adsorption experiments at 1000–8000 ppmv and 30–90°C demonstrated the effectiveness of carbon replicas with regard to capturing toluene. Model simulations further suggest that pore filling of toluene inside the mesopores of template carbon may occur, because the adsorption data showed better agreement with the DR model.
Template; Carbon replica; Montmorillonite; Adsorption; Volatile organic compound.