基于硅胶干燥剂的多孔基材性能测试

Performance Test on Porous Substrate Materials based on Silica Gel Desiccant

多孔性基材作为干燥剂的载体,对除湿转轮的性能有重要影响。本文选择了木浆滤纸(WPFP)、陶瓷纤维纸(CFP)和玻璃纤维纸(GFP)3种多孔基材进行研究。采用Hot Disk、扫描电镜、压汞仪及ASAP2460对3种材料的基本物性进行表征,将基材多次浸泡JN-30硅溶胶,并在恒温恒湿箱中高温高湿工况下进行吸附实验,对比3种基材本身及上胶后的吸附及脱附能力。结果表明:上胶次数对3种材料的影响相似,基材上胶后整体的饱和吸附量增大、达到饱和状态的时间变长,但上胶次数过多会导致每次上胶增加量减少,上胶次数不能超过5次。木浆滤纸相比于陶瓷纤维纸和玻璃纤维纸具有更好的亲水性及更高的上胶率,且亲水性相比于孔隙率对上胶率的影响更大,单位面积基材上胶后整体的吸附量最大、达到饱和状态的时间较长,符合LDF模型的模拟结果,且脱附能力较好,适用于除湿转轮的制作。

Porous substrate materials are essential tor desiccant wheels that typically act as the carrier of desiccant. The study investigated the perionnance of three types of promising porous substrate materials including wood pulp flter paper （ WPFP ） , ceramic fiber paper （ CFP）, and glass fiber paper （GFP）. The elementary properties of the three types of materials were measured via a hot disk, scanning e- lectron microscopy （SEM）, mercury injection apparatus, and a micromefitics gas adsorption analyzer （ASAP2460）. The materials were repeatedly immersed in JN-30 silica sol to obtain the gluing rate. The dynamic adsorption experiments were conducted at a constant tem- perature and humidity chamber under high temperature and high humidity conditions to evaluate the gluing adsorption ability while the de- sorption ability was compared via desorption experiments. The results indicate that a similar influence is induced by increasing the number of gluing times. Unnecessary over-gluing leads to a reduction in the every-time gluing rate and enhanced saturated adsorption quantity. The suggested maximum gluing times con＇esponds to 5. Furthennore, the hydrophilicity of WPFP leads to a stronger adsorption and de- sorption capacity when compared with those of CFP and GFP, and the gluing rate of the WPFP exceeds that of the other two candidates. Theretore, the hydrophilicity dominates the gluing rate as opposed to the porosity. Finally, the highest adsorption quantity per unit area and the saturation time of WPFP during the whole process are observed in the adsorption experiment, and this is in good agreement with the LDF model fitting results. Given that the results of the study verify the numerous advantages of the WPFP, it is the most suitable mate- rial that can be applied in a desiccant wheel.