污泥基活性炭-甲醇工质对吸附/解吸特性

Interdisciplinary research was conducted between sewage sludge reclamation and adsorption refrigeration. Pore structure regulation was investigated using sewage sludge as the main carbon precursor, and effects of KOH-catalytic carbonization and phosphoric-acid catalytic activation were clarified. And four new types of sludge-based activated carbons (WNC-4/3/2/1) were prepared by innovative procedure. Performances in terms of adsorption/desorption capacities, refrigerating capacities and refrigerating power were conducted, based on WNC-methanol adsorption refrigeration working pair. Results suggested that the impregnation process of KOH and phosphoric acid resulted in increasing of microporous and mesoporous structures, respectively. Especially, total-, micro- and meso-porous volumes of the new carbon WNC-4 researched to 0.6960, 0.1641 and 0.5319cm³/g, respectively, which was prepared by combined catalysis of KOH and phosphoric acid. The correlation analysis between the specific surface area/pore structure distribution and Q_L^* showed that degree of mesoporous volumes have the most significant correlation with methanol adsorption capacity (R²> 0.90). The maximum adsorption capacity (Q_L^*) calculated by Langmuir adsorption isotherm model (R²=0.9939) reached to 552.67±23.83mg/g. The equilibrium adsorption and desorption capacities within 40min obtained by Sokoda-Suzuki equation were (372.94±9.504) and (412.55± 8.309) mg/g, respectively. The desorption capacity, refrigerating capacity and power reached to (327.95±10.56)mg/g, (299.55±7.87)kJ/kg and (599.10±8.15) kJ/(kg•h), respectively, under 100°C of desorption temperature.