Abstract
Upcycling route for handling petrochemical waste oil (PWO) is a sustainable alternative to its costly and complex treatment. However, the mishandling of PWO can lead to environmental and health hazards. Finding other valuable usages for PWO is a viable long-term solution. Hence, a new approach for synthesizing carbon nanotube-metal composite from PWO is significantly beneficial because of its environmental and economic benefits. Herein, simple catalytic vapor deposition (CVD) was used to synthesize carbon nanotubes (CNTs) from PWO. Optimal conditions for the CNT synthesis were determined by varying the temperature (900 – 950 oC) and catalyst to carbon precursor ratio at a preset residence time (0.5 h). It was observed that CNTs diameter increased with increasing temperature, but carbon yield decreased. On the other hand, nickel (Ni) nano-layer was deposited on the CNT surface by electroless plating (ELP). The effect of temperature (30 – 70 oC) during ELP on the thickness of the coating and morphological structure was also investigated. Prior to ELP, CNT's surface was treated with H2O2 (1:50 wt. ratio) at 60oC for 2h to improve its dispersibility in an aqueous solution. It was then further sensitized and activated to make it an autocatalytic substrate. As the temperature increased, the amount of Ni deposited into the CNT's surface also increased. At temperature > 60 oC the morphology of the CNT significantly changed. Still, Ni-CNT's structural stability and integrity were maintained even after Ni deposition proving that ELP is a facile approach for the synthesis of a metal-carbon framework.
