Study of adsorption characteristics in silica gel–water adsorption refrigeration

As one of environmentally friendly refrigeration methods, solid adsorption refrigeration has tracked much interest over the world. Silica gel is popularly used in adsorption refrigeration systems as the adsorbent. Like a compressor in a compression refrigeration system, the adsorbent is vital to the performance of adsorption refrigeration systems. In this work, many different silica gel samples were prepared according to their application surroundings in silica gel–water adsorption refrigeration systems. The adsorption characteristics including variations, deterioration, and improvements of the adsorption property were detected. The specific surface area, silanol content, adsorption capacity, and pore size distributions of those samples were tested. The corresponding adsorption isotherms were achieved. The experimental results indicated that the adsorption capacity of the silica gel was influenced by many factors. But pollution by solid particulates was the primary factor to decline the adsorption capacity.