权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Measurement of Diffusion Coefficient of Solute in Porous Material in the Presence of High Pressure Fluid

高压流体存在下多孔材料中溶质扩散系数的测量

基本信息

批准号：
07455308
负责人：
MASUOKA Hirokatsu
金额：
$ 4.35万
依托单位：
HIROSHIMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07455308/
关键词：
Supercritical Fluid Adsorption Equilibria Mass Transfer Ideal Adsorption Solution Model Surface Diffusion BPL Activated Carbon High Surface Area Activated Carbon 高圧力

项目摘要

The adsorption equilibrium loadings of benzene, toluene, and acetone on two adsorbents, a BPL activated carbon and a high surface area activated carbon in the presence of supercritical carbon dioxide were measured at temperature of 313 K and pressures from 1 to 12 MPa. Loading of the pure adsorbates, carbon dioxide, benzene, toluene, and acetone on these activated carbons were also measured.At a constant partial pressure of the adsorbates, all adsorption loadings showed a maximum value at pure state and decreased with increasing pressure. On the same adsorbent benzene and toluene loadings shwed almost the same amount absorbed, while the loadings of acetone were lower than those of benzene and toluene. The adsorption loadings on the high surface area activated carbon were larger than those on the BPL activated carbon. However, pressure dependence was almost the same trend as that of BPL activated carbon. This may imply the effect of carbon dioxide adsorption over the amount of adsorbates and solvent power of carbon dioxide in fluid phase.Prediction method of adsorption amounts in the presence of supercritical fluid was examined in this work. An ideal adsorption solution theory (IAST) reported by Prausnitz et al.was used. Prediction values of IAST were in good agreement with experimental ones.Dynamics of adsorption of benzene dissolved in supercritical carbon dioxide on activated carbon were studied by analysis of breakthrough curves in the nonlinear region of the adsorption isotherm. Surface diffusion was found to be a main transport mechanism inside the adsorbent particles. Surface diffusion coefficients were similar to values reported by other investigators under lower pressures.

在温度313 K、压力1 ~ 12 MPa下，测定了苯、甲苯和丙酮在BPL活性炭和高比表面积活性炭上的吸附平衡负荷。测定了纯吸附质、二氧化碳、苯、甲苯和丙酮在活性炭上的吸附量，在吸附质分压一定的条件下，纯吸附质的吸附量均出现最大值，随着压力的增加，吸附量逐渐减小。在同一吸附剂上，苯和甲苯的吸附量基本相同，而丙酮的吸附量低于苯和甲苯。在高比表面积活性炭上的吸附负荷大于在BPL活性炭上的吸附负荷。然而，压力依赖性几乎与BPL活性炭的趋势相同。这可能暗示了CO2吸附对吸附物量和CO2在流体相中的溶解能力的影响。采用Prausnitz等人提出的理想吸附溶液理论（IAST）.通过对吸附等温线非线性区穿透曲线的分析，研究了超临界CO2中溶解的苯在活性炭上的吸附动力学。表面扩散被认为是吸附剂颗粒内部的主要传输机制。表面扩散系数与其他研究者在较低压力下报告的值相似。