Evaluation of hydrogen storage capacities on individual adsorbents

Storage of hydrogen is an important component of the hydrogen economy system. Hydrogen must be stored at the production site, as well as at the point of its application. Often, significant part of hydrogen is used directly in the manufacturing process and thus eliminates the necessity of its supply. However, the development of automotive industry and the use of hydrogen for energy production require its storage in order to ensure continuous operation. The need of hydrogen supply itself increases with a use of alternative energy sources. These sources do not allow a constant supply of energy and, as a result, hydrogen serves as an intermediary: an energy carrier. The drawback of its broader application is a low-density storage in conventional pressure and cryogenic tanks, where it is necessary to use high pressures, respectively very low temperatures. Therefore, various types of metal-hydride and adsorption storage tanks are widely tested. Technology of hydrogen adsorption on carbon materials is effective only at cryogenic temperatures and so liquid nitrogen with temperature of 77 K (-196.15 degrees C) was used for the purpose of lowering the temperature of the storage device. This article discusses the possibilities of use of cryogenic temperatures in the adsorption of hydrogen on materials with broad surface area whereby liquid nitrogen is used to lower the temperature. The method of measuring the amount of adsorbed hydrogen was used to determine and quantify the amount of stored hydrogen. (C) 2014 Elsevier Ltd. All rights reserved.