Low cost processing aid from oil refinery waste for compounding of styrene/butadiene rubber

Abstract

Data have been obtained in an attempt to use the oily sludge that is a dumped waste of petroleum refineries. The sludge, after purification, was used as a processing aid in the sulphur vulcanisation of styrene/butadiene rubber, in which carbon black is used as filler. Compounds containing aromatic oil were used as the control. Different mixes, containing varying concentrations of aromatic oil/refinery sludge were prepared. The mixes were evaluated for different cure characteristics and the vulcanisates were tested for various physical properties and chemical crosslink density. Aging resistance of the vulcanisates was also evaluated. Processability studies were carried out for the carbon black systems under review. It was found that the optimum cure time is reduced significantly when aromatic oil is replaced completely with refinery sludge. In the evaluation of tensile properties, vulcanisates containing 60% sludge gave the maximum value, while other vulcanisates containing refinery sludge gave values comparable with those containing conventional process aids. It is worthy of note that aromatic oil is becoming prohibitively costly while sludge is a dumped waste of the refinery.