This paper studies the water equilibrium uptake on two type of adsorbents, namely silica gel RD powder and Zeolite FAM Z01. A novel adsorption isotherm model is proposed to regress the experimental data of the both adsorbents. For the silica gel-water pair, the proposed model generates more precise data regression than the classic DA and Tóth equations. In the case of the zeolite-water pair, the new model well fits its unique S-shape isotherms at various adsorption temperatures. The linear behavior at both low and high relative pressure regions, and the sharp rise in between the two regions are accurately captured. The model produces R2 value 0.997 and NRMSE error 3.15% for the former pair, and 0.997 R2 and 6.05% error for the zeolite-water pair in the experiment range.
Keywords: silica gel, zeolite FAM Z01, isotherm model, adsorption chiller and desalination