Comparative Study of Cashew Nut Shell Liquid and a Commercial Demulsifier for Treating Crude Oil Emulsions

Cashew Nut Shell Liquid (CNSL), a natural phenolic liquid extracted from locally sourced raw materials, and Phasetreat-4633 (a commercial demulsifier) were diluted with xylene and butanol and used as demulsifiers in the treatment of crude oil emulsions. Laboratory simulated crude oil emulsions dosed with different concentrations of CNSL and PT-4633 were the basis for comparison of demulsifier performance via the bottle test method.

Different factors affecting demulsification efficiency such as; water content, demulsifier concentration, and solvent type were investigated at 10%, 30%, and 50% water content. The data obtained showed that the rate of water separation increases with increasing concentration and water content of the demulsifiers and emulsion respectively. Among the demulsifier-solvent combination employed in this study, Phasetreat-4633 in butanol recorded the most efficient water separation with optimal (100%) separation recorded after 5 minutes at 40 ppm and 50 ppm concentration, 50% water content and 60℃.

From the obtained results, the investigated demulsifiers have great potential with butanol as a solvent in the resolution of crude oil emulsions in shorter times. This behavior can be attributed to the synergetic effect of butanol as a solvent. Hence, butanol can be regarded as a better solvent substitute to xylene, due to its attributive synergetic effect, low cost and toxicity levels, unlike xylene which is more toxic and expensive.