The effect of dydrophobic modification of zelites on CO2 absorption in different solvents

• Autor(a) principal: Sumin,Lu
• Data de Publicação: 2010
• Outros Autores: Youguang,Ma, Shuhua,Shen, Chunying,Zhu
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Brazilian Journal of Chemical Engineering
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0104-66322010000200011
• topic: Modified zeolite; Absorption enhancement; Microcosmic model; Adsorbed particles

The hydrophobicity of zeolite was achieved by a method of hydrothermal synthesis combined with acid treatment for the enhancement of CO2 absorption. The influence of zeolite before and after modification on the absorption of CO2 in three kinds of solvents (water, cyclohexane and soy bean oil) was investigated and many different effects were observed. In aqueous solution, modified zeolite showed a very remarkable enhancement with a maximum enhancement factor of 2.2 for a ratio of SiO2 and Al2O3 equal to 86. However, no measurable enhancement effect was found in cyclohexane solution by adding modified zeolite, although unmodified zeolite showed a weak increase in the absorption rate. In soybean oil, almost no change in CO2 absorption was obtained for both unmodified and modified zeolites. These results indicate that the particles with an enhancement effect for CO2 absorption rate need to have two properties, hydrophobicity and a high adsorption capacity for the solute. For predicting the enhancement factor of CO2 absorption by solid particles, a three-dimensional heterogeneous microcosmic mass transfer model was developed, in which the influence of several parameters and the interaction between particles were mainly considered. The results predicted by the present model show good conformity to experimental data, indicating that the model is rational and applicable for the enhancement process of CO2 absorption by modified zeolite particles.