Abstrakt

Bio-paraffin mixtures production over different catalysts

Oliver Visnyei

 The hydrocarbons of bio-paraffin mixtures are mostly in diesel fuels (less in aviation fuels) boiling range; therefore they can be promising alternative fuel component. Moreover, the bio-paraffin mixture can be used in the cosmetics and pharmaceutical industry, food industry, in petrochemical industry, for example C14-C18 paraffin hydrocarbons can play important role in detergent production (e.g. for lubricant or household detergents).The main production possibilities of bioparaffins are the followings: integrated Fischer-Tropsch (F-T.) synthesis from biomass derived syngas, from lignocellulose through simple sugars, from bioethanol via dehydrogenation, oligomerization and saturation, from natural/waste triglycerides, from natural/waste fatty acids. The aim of our research was the investigation of (catalytic) hydrogenation of waste fatty acid mixture over different catalysts (sulphided or non-sulphided CoMo/Al2O3, NiMo/Al2O3, and Pt/Al-SBA-15 to valuable bio-paraffin for JET/diesel fuel blending components, petrochemicals or other valuable products).We investigated the effects of catalytic system (reactor, catalyst properties, process parameters – temperature: 250-350 °C, pressure: 40 bar, liquid hourly space velocity: 1,0-3,0 h-1, hydrogen/feedstock volume ratio: 450 Nm3/ m3) on the yield and quality (e.g. chain length, isoparaffin content, content of non-paraffinic components) of the paraffin mixture and they applicability.We carried out the catalytic (hydrogenation) experiments in a (pilot scale) high-pressure reactor system, which contained a tubular down flow reactor with 100 cm3 effective volume and all the equipment and devices applied in the reactor of an industrial hydrotreating plant.The properties of the feedstocks and the products were determined by standardized methods and they composition with gas chromatographic method, respectively.Based on the obtained results, all the catalysts are suitable for production of bioparaffins from waste fatty acids. Yields of main products changed in function of catalyst compositions (sulphided NiMO/Al2O3> sulphided CoMo/ Al2O3) > non-sulphided NiMo/Al2O3 ≥ non-sulphided CoMo/Al2O3> Pt/Al-SBA-15). The paraffin mixtures with relatively high isoparaffin content were obtained over non-sulphided CoMo/Al2O3 and Pt/Al-SBA-15 catalysts.