Changes in surface chemistry of activated carbons by wet oxidation
Changes in surface chemistry of activated carbons by wet oxidation
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DOI：
10.1016/s0008-6223(00)00048-8
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发表时间：
2000-01-01
期刊：
影响因子：
10.9
通讯作者：
Carrasco-Marín, F
中科院分区：
文献类型：
--
作者：
Moreno-Castilla, C;López-Ramón, MV;Carrasco-Marín, F
用H_2O_2、（NH_4）（2）S_2O_8和HNO_3对一系列不同活化程度的活性炭进行氧化，以引入不同的氧表面络合物。采用程序升温脱附（TPD）、X射线光电子能谱（XPS）、傅立叶变换红外光谱（FTIR）、盐酸滴定、氢氧化钠滴定、零电荷点pH值测定和甲醇催化脱水等方法研究了活性炭氧化处理后表面化学的变化。结果表明，（NH_4）（2）S_2O_8处理的土壤总氧和表面酸基含量均最低。然而，该处理产生具有最高酸强度的酸基团。这可能是因为它有利于固定羧基靠近其他基团，如羰基和羟基，这提高了它们的酸性。(C)2000爱思唯尔科技有限公司版权所有。
A series of activated carbons with different degrees of activation were oxidized with H2O2, (NH4)(2)S2O8 and HNO3 in order to introduce different oxygen surface complexes. Changes in the surface chemistry of the activated carbons after their oxidizing treatments were studied by different techniques including temperature-programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), Fourier transformed infrared spectroscopy (FTIR), titrations with HCl and NaOH, measurements of the pH of the point of zero charge and catalytic dehydration of methanol. Results showed that treatment with (NH4)(2)S2O8 fixed the lowest amount of both total oxygen and surface acid groups. However, this treatment yielded the acid groups with the highest acid strength. This could be because it favors fixation of carboxyl groups close to other groups, such as carbonyl and hydroxyl, which enhances their acidity. (C) 2000 Elsevier Science Ltd. All rights reserved.