Development of thermal conductive consolidated activated carbon for adsorption refrigeration Original Research Article

A new type consolidated composite activated carbon (AC) was developed with a host matrix of expanded natural graphite treated with sulfuric acid (ENG-TSA). Samples with different density, different grain size of AC, and different proportion of AC were produced and thermo-physical properties were evaluated. Results show that the highest effective thermal conductivity and thermal diffusivity of consolidated composite AC were 34.2 W m−1 K−1 and 3.89 × 10−5 m2 s−1, which were 150 times and 72 times higher, respectively, than ordinary granular AC. The permeability of adsorbents ranged between 1.24 × 10−14 and 7.81 × 10−10 m2 while the density ranged between 215 and 448 kg m−3. The adsorption performance for composite AC and granular AC were evaluated by fitting experimental data with the equilibrium Dubinin–Astakhov (D–A) equations. Results show that the addition of ENG-TSA can improve the performance of adsorption refrigeration machines by increasing the concentration swing.