ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Adsorption of SO2 on alumina
P. Fellner, J. Jurišová, V. Khandl, A. Sýkorová, and J. Thonstad
Department of Inorganic Technology, Faculty of Chemical and Food Technology, Slovak University of Technology, SK-812 37 Bratislava, Slovakia
Received: 2 December 2005 Revised: 9 February 2006 Accepted: 9 February 2006
Abstract: The adsorption of SO2 on alumina used in the aluminium industry, the so-called smelter-grade alumina, was studied in the temperature range 15–120°C. It was found that at temperatures lower than 40°C, sulphur dioxide was bonded to alumina reversibly by physical forces, and the adsorption could be described satisfactorily by the Langmuir adsorption isotherm. The heat of adsorption was estimated to be −33 kJ mol−1. At temperatures ranging from 80°C to 120°C, which prevail in dry scrubbers in the aluminium industry, the heat of adsorption was determined to be −56 kJ mol−1. When SO2 was adsorbed at temperatures higher than 80°C, about 30 % of the SO2 could not be desorbed even if the samples were heated up to 250°C. In the presence of SO2 and oxygen, the formation of sulphate was observed at temperatures above 90°C.
Keywords: adsorption equilibrium - sulphur dioxide - alumina - Langmuir isotherm - Freundlich isotherm
Full paper is available at www.springerlink.com.
Chemical Papers 60 (4) 311–314 (2006)