Synthesis of nanoparticle of carbon

International audienceFriction and wear are the first causes of the decrease of the performances and the durability of mechanical systems. The role of lubrication is to minimise friction between the sliding surfaces and to protect them from wear. Conventional liquid lubricants are constituted of base oil and additives presenting specific properties, such as friction reduction, anti-wear or anti-oxidising action. Commercial lubricants generally use graphite and petroleum-based oils because of their recognised lubricating properties, their stability and low cost. However, such lubricants induce health and environmental hazards due to their life cycle. The aim of this work is to investigate the possibility to use local biomass in order to produce environmentally-friendly lubricants. Local vegetable oils are interesting candidates because of their inherent qualities like renewability, bio-degradability, non-toxicity. So, the first objective consists in finding an optimal mixture of mineral oil and vegetable oil validated by a compromise between environmental impact and cost of the lubricant. Our study mainly concerns the synthesis of new friction reducer additives. New carbon phases are obtained from glycolic solutions, stemming from by-products of our agriculture, using the spray-pyrolysis technique. This technique consists in nebulising in the form of micro-droplets a solution of saccharose, transported via a carrier neutral gas in a tubular oven heated at temperature ranging from 600°C to 1,000°C. Carbon nanoparticles are then obtained. Here are described the promising first results related to the determination of the optimal synthesis conditions, i.e. the catalyst concentration, the carrier gas pressure and the temperature of the tubular oven. Scanning electron microscopy and Raman spectrometry analyses are carried out, allowing us to observe the spherical shape and the porosity of the particles and to determine the graphitisation degree of the carbon phases