Characterizations of Activated Carbon−Methanol Adsorption Pair Including the Heat of Adsorptions Jun W. Wu,* ,†,‡ S. Hadi Madani, § Mark J. Biggs, ∥,⊥ Pendleton Phillip, §,# Chen Lei, † and Eric J. Hu* ,† † School of Mechanical Engineering, The University of Adelaide, South Australia, 5005, Australia ‡ Shanghai DFYH Tech Services Co., Ltd, 1255 Xikang Rd., Putuo District, Shanghai 200060, P.R. China § Ian Wark Research Institute, University of South Australia, Mawson Lakes, South Australia 5095, Australia ∥ School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia ⊥ School of Science, Loughborough University, Leicestershire LE11 3TU, U.K. # School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia 5005, Australia * S Supporting Information ABSTRACT: This paper presents adsorption isotherms and isosteric heats of adsorption for methanol vapor adsorption for two commercially available activated carbon samples207EA granules and WS-480 pellets (Calgon Carbon, U.S.A.)which were also fully characterized using nitrogen sorption at 77 K. The heat of adsorption of methanol as a function of loading was determined using the Clausius−Clapeyron approach with isotherms obtained at 5 °C, 15 °C, and 25 °C. The isosteric heats of adsorption increased sharply at the small coverage due to increasing effect of condensation heat with coverage. The heat reached a maximum and then varies little with loading, with the average values at around 46.6 kJ/mol for 207EA and 45.1 kJ/mol for WS-480. The higher heats of adsorption for the former activated carbon reflect its more microporous nature (around 78 % compare to 62 % for WS-480 activated carbon). The heat of adsorption data is also comparable to that obtained elsewhere for other activated carbons. 1. INTRODUCTION Adsorption cooling/heat pump systems have attracted considerable attention 1 over the past few decades due to their promise to reduce greenhouse gas emissions and Oz-layer depletion problems. The thermophysical properties of the adsorbent/adsorbate pair significantly affect the performance of adsorption-based cooling systems. 1 This observation has motivated much effort in determining these properties for systems including: zeolite/water, silica gel/water, activated carbon/methanol, activated carbon/ethanol, and carbon/ ammonia pairs. 1,2 Of these, activated carbon/methanol offers considerable promise; 3,4 methanol has a high latent heat of evaporation promoting small size systems and avoids corrosion issues for steel and copper at working temperatures below 120 °C. This system also has the advantage that methanol has a freezing point below that of water and, thus, systems based on it can be used to make ice. 1 Extensive experimental studies have already been made to determine the efficacy of adsorption cooling systems using different combinations of adsorbent/ adsorbate working pairs. 5−15 Few have addressed adsorption isotherms of the activated carbon/methanol pair, and the heat of adsorption data are scarce. 8,13,14 In this paper, we report multiple temperature methanol adsorption isotherms and their resulting isosteric heats of adsorption for two different commercial activated carbons: a granular activated carbon, 207EA, and a pelleted activated carbon, WS480. Although these carbons are used primarily for water treatment and volatile organic compound capture, respectively, 16 each is also readily available and relatively inexpensive. We propose to assess their appropriateness for adsorption-based systems. In addition to the methanol data, we have determined for both activated carbons their porosity, BET specific surface area, and pore size distributions. The methanol results have been correlated with these characteristics as well as compared with data published elsewhere for methanol adsorption on other carbons. 17 2. MATERIALS AND METHOD The coal-based, activated carbon 207EA, a granular material of particle size 4 × 10 mm and WS480, a pelleted activated carbon (diameter 4 mm) were sieved prior to use to remove any crushed carbon. Both activated carbons were obtained from Calgon Carbon, U.S.A. 16 Both carbons were degassed at 250 °C and 10 −5 kPa for 4 h prior to the adsorption experiments. Received: December 8, 2014 Accepted: May 18, 2015 Published: May 22, 2015 Article pubs.acs.org/jced © 2015 American Chemical Society 1727 DOI: 10.1021/je501113y J. Chem. Eng. Data 2015, 60, 1727−1731