Abstract. Adsorption appliances may turn out to be an alternative to compression-type refrigerators. The adsorption refrigeration machine may be driven by a low-grade heat source, especially solar energy. Solar adsorption cooling systems are environment-friendly and have zero ozone depletion potential. Therefore, the adsorption refrigeration is one kind of energy saving refrigeration methods. The merits of the adsorption refrigeration systems will be more significant especially when it is used in vehicles (automobiles, ships and locomotives), to preserve food and medicines and in air-conditioning. The paper presents the advantages and disadvantages as well as the evolution of the technology of adsorptive refrigeration systems. The methods of improving of adsorption refrigeration systems through improvements in adsorbents properties, use of advanced cycles and hybrid systems is also presented. Possible applications and perspectives for development of adsorption cooling systems are also analyzed. The paper describes a test stand of the adsorption-desorption refrigeration. The present investigations have been carried out utilizing the activated carbon granules as an adsorbent and methanol as an adsorbate. The paper demonstrates the measurement of temperature changes in the adsorbent bed and condenser during adsorption-desorption cycles.

Active carbon-methanol pair appears to be suitable for adsorptive cooling systems. The porous structure of commercial active carbon was modified by potassium hydroxide treatment at 750°C. Such treatment develops the specific surface area of carbon, changes nature of its surface and significantly increases the heat of wetting. The applied way for active carbon modification gives possibility of modeling porous structure, character surface and heat effects of carbonaceous materials for adsorptive refrigerators.Keywords Refrigeration · Active carbon-methanol pair · Heat effects of adsorption Abbreviations C wA specific heat of methanol, J/g°C C wC specific heat of carbon, J/g°C E 0 characteristic energy of adsorption, kJ/mol Q heat of wetting, J S BET specific surface, m 2 /g S me mesopores surface area, m 2 /g W 0 volume of micropores, cm 3 /g V A volume of methanol used in the measurement, cm 3 V p volume of pores, cm 3 /g d A density of methanol, g/cm 3 d HK slit pore width, nm m C mass of carbon, g T increase of temperature,°C

Abstract. Economic reasons and quest for new solutions based on recovering the energy have provoked an increase of interest in the adsorption technology in the refrigeration industry. The confirmation can be the fact that number of published research is on rise. Adsorption appliances may turn out to be an alternative to compression-type coolers. They use ecological chemical agents instead of substances which are aggressive and harmful to the environment. For regeneration of adsorptive refrigeration systems one can use cheap energy in a form of: industrial waste heat, energy of solar radiation and cheap electric power. The paper presents principles of operation as well as advantages and disadvantages of adsorptive refrigeration systems. Basing on literature the most frequently used adsorbentadsorbate systems -which are employed in refrigeration industry -have been characterized. A review of construction solutions of systems on both laboratory and industrial scale has been made.

Abstract. In this paper commercially available activated WD-extra carbon (Gryfskand) which is applied for water treatment was used. Activted carbon was modified by the following chemical agents: H2O2, HNO3 and HCl. The textural characteristics of the samples were determined by the analysis of physical adsorption isotherms of nitrogen vapor at 77 K. The Boehm titration general procedure was used to determine the distribution of the surface functional groups. Chemical modifications significantly affect the chemical, structural and surface properties of activated carbons. Hydrophobization with ethereal stearic acid was performed on the raw material and samples after chemical modification. Hydrophobic properties of the samples were specified. The relationship of the chemical modification agents with hydrophobization degree was indicated.

No abstract