Adsorption of Direct Yellow 12 onto Ordered Mesoporous Carbon and Activated Carbon
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- 作者：Fengling Liu ; Jiahong Wang ; Liyuan Li ; Yun Shao ; Zhaoyi Xu ; Shourong Zheng
- 刊名：Journal of Chemical & Engineering Data
- 出版年：2009
- 出版时间：November 12, 2009
- 年：2009
- 卷：54
- 期：11
- 页码：3043-3050
- 全文大小：284K
- 年卷期：v.54,no.11(November 12, 2009)
- ISSN：1520-5134
文摘
Mesoporous carbon CMK-3 was prepared using a mesoporous silica SBA-15 as the template, and the adsorption of aqueous direct yellow 12 (DY-12) on CMK-3 and commercial powdered activated carbon (PAC) was studied. X-ray diffraction, N2 adsorption, and transmission electron microscopy results demonstrate that CMK-3 with ordered structure is a true replica of its template SBA-15. CMK-3 and PAC have comparable pore volumes, whereas CMK-3 mainly consists of mesopores, and PAC contains both micropores and mesopores. The adsorption of DY-12 over CMK-3 and PAC could be well-described by the Langmuir isotherm model. The maximum adsorption amounts of CMK-3 and PAC for DY-12 at 25 °C were found to be (303.0 and 161.3) mg·g−1, respectively, indicative of a substantially higher adsorption capacity of CMK-3 compared to that of PAC. DY-12 adsorption processes over CMK-3 and PAC obey pseudosecond-order kinetics. For DY-12 adsorption on CMK-3, the rate constants were (2.82·10−4, 4.43·10−5, and 9.77·10−6) g·mg−1·s−1 at initial DY-12 concentrations of (17.7, 44.3, and 145) mg·dm−3, respectively. In the case of PAC, the rate constants were found to be (1.78·10−5, 9.8·10−7, and 6.7·10−7) g·mg−1·s−1 at initial concentrations of (17.7, 44.6, and 339) mg·dm−3, respectively, reflecting much lower adsorption rates over PAC than those over CMK-3. Furthermore, the intraparticle diffusion of DY-12 over CMK-3 and PAC was elucidated using the Weber−Morris model. The present results clearly verify the importance of mesopores in the adsorption of aqueous DY-12.