Study On Preparation Of Liquid Fuel By Deoxygenation And Liquefaction Of Seaweed Biomass

Although the uncontrolled mining and use of traditional fossil fuel,seriously pollute the environment,people's lives and social development can not be separated from the supply of energy.At the same time,the increasing lack of fossil fuel restricts the development of society.So it is needed to find an environmentally friendly and renewable energy to replace the traditional fossil fuel.Biomass energy,as a renewable energy with carbon zero emission,is not only rich in reserves,but also widely distributed.If it can be reasonably exploited,it can relieve the excessive reliance on traditional fossil fuels and also reduce the emission of polluting gas(NOx,COx,SO2).Biomass can be divided into terrestrial biomass and marine biomass,between which terrestrial biomass has received more and more attention because of its high photosynthetic efficiency and fast growth rate.Co-deoxy-liquefaction of macroalgae(Laminaria japonica,LJ)and lignocellulosic biomass(Sweet potato vine,SPV)for hydrocarbon oil production and the effects of mass ratio of SPV/LJ on product distribution were investigated in this study.The highest yield of liquid oil was obtained at the SPV/LJ mass ratio of 1:1,at which alkanes with the relative content of 14.36% were detected in the produced liquid oil with the lowest oxygen content of 3.23% leading to the higher heating value up to 43.55 MJ/kg.The results showed that different compositions of the feedstocks and the synergistic interaction between SPV and LJ during co-deoxy-liquefaction exerted great effects on properties of the obtained liquid oils.The comparative study of deoxy-liquefaction of marine biomass(Enteromorpha prolifera,Giant kelp and Undaria pinnatifida)and terrestrial biomass(cotton stalk,sweet potato straws and plane leaves)was investigated.The results showed that the oil yield of marine biomass was higher than that of the terrestrial biomass and that the relative content of each kind of compounds in the six bio-oils was different from each other,which is closely related with the compositions and content of the feedstocks.Besides,the content of nitrogen-containing compounds of the bio-oil obtained from the marine biomass was higher,which can be due to the existence of the protein in the feedstock.Therefore the liquid oils obtained from the marine biomass should be denitrified to improve the quality.The composite molecular sieve of ZSM-5/MCM-41 was synthesized by usingsodium silicate as the silica-alumina source.The characteristics of this catalyst were carried out by using SEM,XRD,FTIR,N2 adsorption-desorption.The effect of the catalyst on the deoxy-liquefaction of Gelidium amansii was investigated.The results indicated that the oxygen and nitrogen content of the liquid oil significantly decreased,while the heating value and the relative contents of the alkanes and the aromatic hydrocarbons increased with the catalyst added during the liquefaction process.In addition,the content of the nitrogen containing compounds decreased.This indicated that the catalyst played an important role during the liquefaction of the marine biomass.