Physical and chemical properties of carbons synthesized from xylan, cellulose, and Kraft lignin by H3PO4 activation
Physical and chemical properties of carbons synthesized from xylan, cellulose, and Kraft lignin by H3PO4 activation
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DOI：
10.1016/j.carbon.2005.12.002
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发表时间：
2006-07-01
期刊：
影响因子：
10.9
通讯作者：
Rockstraw, David A.
中科院分区：
文献类型：
--
作者：
Guo, Yanping;Rockstraw, David A.
研究了在不同工艺条件下，以工业木聚糖、纤维素和硫酸盐木质素为原料，采用H3PO4活化法制备炭的物化性能。结果表明，前驱体在酸性条件下活性越强，就越容易形成孔洞，尤其是介孔。此外，Boehm滴定和傅里叶变换红外光谱(FTIR)表征结果表明，这些碳表面的官能团既有温度敏感组分，也有温度不敏感组分。温度敏感组分主要是由于原料在低温酸性条件下的水解，以及活化过程中活化混合物与氧气的反应，特别是在低浸渍比时。这些表面基团在高温下分解。温度不敏感的贡献主要由H3PO4(或焦磷酸和多磷酸)与前驱体反应产生的含磷基团和含有羰基的基团组成。即使在较高的活化温度下，这部分表面官能团也是稳定的。本研究还证实了前驱体性质、H3PO4与前驱体的浸渍比、活化温度是影响最终活性炭制品性能的重要因素。(C)2005爱思唯尔有限公司。保留所有权利。
Physical and chemical properties of activated carbons produced from commercial xylan, cellulose, and Kraft lignin by H3PO4 activation at various process conditions were studied. The results show that the more reactive the precursor under acidic conditions, the easier the porosity development, particularly mesoporosity. In addition, Boehm titration and Fourier Transform Infrared Spectroscopy (FTIR) characterization results demonstrated that the functional groups on the surfaces of these carbons consist of both temperature-sensitive and temperature-insensitive components. The temperature-sensitive component is primarily caused by the hydrolysis of raw materials under acidic conditions at low temperature, and the reaction between activation mixture and oxygen in the process of activation, particularly at low impregnation ratio. These surface groups decompose at high temperature. The temperature-insensitive contribution is mainly composed of phosphorus-containing groups arising from the reaction of H3PO4 (or pyro- and polyphosphoric acids) with precursor, and carbonyl-containing groups. This part of surface functional group is stable, even at high activation temperatures. This study also confirmed that the nature of precursor, impregnation ratio between H3PO4 and precursor, and activation temperature are important factors affecting the properties of final activated carbon products. (C) 2005 Elsevier Ltd. All rights reserved.