Study on consolidated activated carbon: Choice of optimal adsorbent for refrigeration application

Abstract

For refrigeration condition in order to choose an optimal consolidated composite activated carbon (AC), the thermal conductivity, permeability, equilibrium adsorption performance, and non-equilibrium adsorption performance were studied. Six samples of three types of adsorbents (consolidated AC with expanded natural graphite treated with sulfuric acid (ENG-TSA), consolidated AC with expanded natural graphite (ENG) and granular AC) with different density and different grain size were produced and compared. Experiments showed that the thermal conductivity and permeability of consolidated AC with ENG-TSA are between 6.75 to 7.45W/mK and 2.00×10−12 to 1.00×10−11m2, respectively, when the density is ranged between 350kg/m3 and 450kg/m3. The study on the equilibrium and non-equilibrium adsorption performance indicated that the addition of ENG-TSA helps to improve the concentration swing. The cycle time of consolidated AC with ENG-TSA decreases significantly compared with that of consolidated AC with ENG and granular AC. For the optimal results from the matrix of ENG-TSA although the bulk density of AC decreases, the volume cooling power is 30% improved in comparison with the results of granular AC because the cycle time decreases significantly.