Ion Exclusion Desugarisation

Ion exclusion is a chromatographic process which separates components from an impure feedstock on the basis of molecular size and charge. A pilot plant ion exclusion separator was constructed to determine the technical and economic feasibility of recovering sugar from refinery jet 4 (the feedstock identified as most promising in terms of ease of treatment). Extensive tests on jet 4 from the Malelane refinery (a carbonatation-sulphitation refinery) have demonstrated the technical feasibility of the process. Sugar boiling trials on the sucrose fraction recovered from the ion exclusion pilot plant have shown considerable improvements in crystal morphology, recoverable sucrose and crystal colour. The effects of the pilot plant operating conditions on the quantity and quality of sugar recovered are discussed.