Synthesis of some additives from upgraded petroleum residues of lubricant oil refineries

Abstract

Aromatic extract residues occur as by-products in petroleum refineries, through the process of refining lubricant oil. These residues are considered as having low economic value, and their disposal may even cause problems for the refineries. The present work looks at upgrading these residues by using them to synthesise different petroleum additives, e.g., antioxidants, ashless dispersants, pour-point depressants, and flow improvers for lubricating crankcase oils and for fuels. The antioxidants were synthesised by reacting mono-aromatics with phosphorus pentasulphide (P2S5) in the presence of zinc oxide (ZnO). Ashless dispersant additives were synthesised by reacting alkylated mono-aromatics (using chlorinated paraffin wax as an alkylating agent) with formaldehyde solution (37%) in the presence of polyisobutylene succinimide. Fuel pour-point depressants and flow improvers can be synthesised by acylating di-aromatics via a Friedel-Crafts reaction. Comparative evaluation of the synthesised products with commercial additives showed them to have good comparative performance properties.