Hydrothermal liquefaction of olive oil solid mill waste with montmorillonite supported metal catalysts

Due to the limited resources of fossil fuels, which supply most of the world's energy needs, and the pollution caused by these energy sources, the importance of renewable energy sources has increased. It is well known that development studies on the energy conversion technology of biomass as an alternative energy source are increasing. In this study, the effects of different catalysts and reaction conditions on the efficiency of bio-oil production from olive pomace by hydrothermal liquefaction method were investigated. First, the effects of montmorillonite clay, kaolin clay and bentonite clay as catalysts were investigated. The highest yield of bio-oil was obtained with montmorillonite. Then 5 different metals (chromium, cobalt, zinc, manganese, nickel) were loaded on montmorillonite by pillaring method and characterized by XRD, XRF, BET, SEM methods. The effects of liquefaction conditions (temperature, reaction time, catalyst amount, solid-liquid amount) with the nickel-loaded montmorillonite catalyst were studied. The contents of the bio-oils obtained from the experiments were determined by GC-MS and the heating values were determined by elemental analysis. The highest bio-oil yield (42.01%) was obtained at a temperature of 275°C, a catalyst amount of 1g Ni/Mmt, a reaction time of 30 minutes and a solid-liquid ratio of 1/10.