Polyolefin and Polystyrene‐Derived Carbon Nanotubes: Catalysts for Oxidative Desulfurization Under a Biphasic System

Abstract The conversion of plastic solid waste into carbon nanotubes (CNTs) via chemical vapor deposition (CVD) and the effectiveness of these CNTs as catalysts for oxidative desulfurization (ODS) of a simulated fuel were investigated. The primary focus is on the use of CNTs synthesized from various polymer sources, including polyolefins and polystyrene (PS), to remove sulfur compounds using hydrogen peroxide (H 2 O 2 ) as an oxidant. The surface modification of CNTs by using acids (H 2 SO 4 or HNO 3 ), the influence of the carbon feedstock (polyolefins vs PS), the use of co‐catalysts, and the effect of the extractant phase were all evaluated on the oxidative removal of dibenzothiophene from a simulated fuel. Results revealed that CNTs derived from polyolefins displayed higher desulfurization efficiency (up to 77% in 8 h), with nitric acid‐treated CNTs showing the best performance under oil‐water biphasic systems. Replacing water with acetonitrile and adding a co‐catalyst (formic acid) resulted in a desulfurization of 91% in 2 h of reaction. Under certain conditions, C─S bond cleavage was observed. This research contributes to the valorization of plastic solid waste and the reduction of atmospheric pollution, promoting circular economy practices and environmental sustainability.