Variation in sooting characteristics and cetane number of diesel with the addition of a monoterpene biofuel, α-pinene

International audienceDiesel fuel combustion generates soot particles, which are harmful for human health and the environment. To reduce soot emission, various solutions are proposed in the literature such as the use of metal-additives in fuels, fuel blending with biofuels, and the use of diesel particulate filters. This study analyses the effect of the addition of a bicyclic monoterpene hydrocarbon biofuel, α-pinene to diesel in different proportions on the fuel cetane number, sooting propensity, and the physicochemical properties of soot nanoparticles. The addition of 10% α-pinene to diesel exhibited a synergistic effect on sooting tendency and reduced the threshold sooting index of diesel by 21%, even though α-pinene is an unsaturated hydrocarbon, and had a minimal impact on cetane number, which reduced from 63.5 for diesel to 61.5 for the blended fuel. The influence of α-pinene addition to diesel on soot nanostructural characteristics and reactivity is determined through different characterization approaches including HRTEM, TGA, XRD, SEM-EDX, and EELS. The results indicate that α-pinene addition to diesel imposes curvatures in soot nanostructure, creates relatively smaller fringes (PAHs) in soot, and reduces soot aromatic content to improve soot oxidation rate

Crude bioglycerol derived sulfur-doped carbon material for electrooxidation of bioglycerol and other alcohols

By 2030, most developing countries aim to produce affordable and clean energy in accordance with UN Sustainable Development Goals. Thus, there has been a surge of interest in biofuels such as biodiesel. However, as the production of biodiesel increases, so does the issue of excess bioglycerol, which is a by-product of the process with no large-scale applications. To address this, the cost-effective utilization of bioglycerol, for example, in direct bioglycerol fuel cells or to synthesize carbon-based materials, is necessary. This study focuses on exploring the potential of used cooking oil to produce crude bioglycerol and further utilizing it as a carbon and energy source. Crude glycerol-based sulfur-doped carbon materials (S-CGBC) with graphene oxide-like appearance were synthesized using an acid dehydration method. The synthesized carbon material was fully characterized and was further analyzed to determine its potential as support materials on nickel foam for glycerol electrooxidation reaction (GEOR) and crude bioglycerol electrooxidation reaction (BGEOR). S-CGBC demonstrated good catalytic activity and stability for both GEOR and BGEOR, with high peak current densities of 262 mA/cm2 and 272 mA/cm2 at 0.6 V vs Ag/AgCl for GEOR and BGEOR, respectively. The HPLC analysis revealed 78.3% glycerol after 15 hours of bulk electrolysis of 1 M glycerol. The results of this study highlight the potential of waste crude bioglycerol as a good source of energy as well as of carbon materials