Development and adsorption properties of diatomite-LiCl composite desiccant

doi:10.11949/j.issn.0438-1157.20160048

Abstract

Abstract:

Diatomite-LiCl composite desiccant was fabricated by impregnating LiCl into pores of porous diatomite. The surface area and pore parameters of composite desiccant were measured by Micromeritics gas adsorption analyzer (ASAP 2020). With improvement of the analyzer, water sorption capacity of composite desiccant was tested and compared to pure diatomite and conventional silica gel. Researches on nitrogen adsorption suggested that due to the impregnated salt particles, the surface area and pore volume of composite desiccant were smaller than pure porous media. Water sorption tests showed that the composite sample had water uptake much higher than that of pure diatomite and silica gel. Besides, sorption characteristic curves were fitted based on Polanyi potential theory. The result showed that the curve of composite desiccant could be divided into three sections.

Key words: adsorption, porous media, lithium chloride, morphology, composite desiccant

摘要：

以硅藻为多孔基质，氯化锂为浸渍盐，配制了硅藻-氯化锂复合除湿剂。采用麦克公司生产的ASAP2020物理吸附仪测量了复合硅藻的比表面积、孔径等微观结构参数。通过对吸附仪的改进，对复合除湿剂的水蒸气吸附性能进行了测试研究，并与纯硅藻基质以及常见硅胶除湿剂的吸附性能进行对比。氮气吸附测试显示复合除湿剂的比表面积、孔体积参数较纯硅藻基质有明显下降，表明氯化锂颗粒充分浸入到硅藻孔隙中。水蒸气吸附测试表明复合硅藻除湿剂的吸湿性能较纯硅藻基质及硅胶除湿剂有着显著提高。此外，基于Polanyi吸附势理论对复合除湿剂吸附特征曲线的拟合研究发现复合除湿剂的吸附特征曲线包括3个部分。

关键词: 吸附, 多孔介质, 氯化锂, 形态学, 复合除湿剂

CLC Number:

TP172

ZHENG Xu, WANG Ruzhu, GE Tianshu. Development and adsorption properties of diatomite-LiCl composite desiccant[J]. CIESC Journal, 2016, 67(7): 2874-2879.

郑旭, 王如竹, 葛天舒. 硅藻-氯化锂复合除湿剂制备及吸附性能[J]. 化工学报, 2016, 67(7): 2874-2879.

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