Molecular imprinting for the selective adsorption of organosulphur compounds present in fuels

A novel approach to the potential desulphurisation of fuels such as diesel is proposed. It relies on the creation of recognition sites complementary to sulphur-containing compounds in highly cross-linked polymeric matrices using the molecular imprinting technique. Dibenzothiophene sulphone (DBTS) was used as template for the preparation of molecularly imprinted polymers (MIPs). Four different polymers were synthesised using 5-octyloxy-1,3-bis(4-ethenylphenyl)benzenedicarboxamide or methacrylic acid and divinylbenzenes or ethylene glycol dimethacrylate as functional monomers and cross-linkers, respectively. Three polymers showed better binding of DBTS than non-imprinted controls, and were also superior in adsorption of organosulphur compounds such as dibenzothiophene (DBT) and benzothiophene (BT) present in a model mixture. A maximum adsorption of 66 mg DBT per gram of polymer was observed at a polymer load of 10 g l-1 and an initial DBT concentration of 3.69 g l-1. The polymers also showed selectivity for fluorene.