Hydrolysis Of Biomass To Furfural And 5-HMF

Many chemicals can be obtained by hydrolysis of lignocellulose.The conversion of corncobs to furfural using biphasic system or M-O-L catalyst and the residue to 5-HMF were investigated to make full use of lignocellulose.Furfural was usally extracted from the reaction system by steam stripping process in traditional furfural production,which producing large amounts of waste water and waste residue.And side-reactions are the main reasons for low furfural yield.In this paper,toluene was used as extraction agent to decrease the furfural decomposition and achieve high furfural yield.Lewis acids(FeCl3,NaCl,CaCl2 and ZnCl2),dosage Lewis acid and Bronsted acid,temperature,concentration of sulfuric acid and dosage of toluene on furfural yield were also investigated.And the highest yield of furfural 61.36%was obtainted under the conditions of FeCl3 of 0.18mmol/g biomass o,tempurature of 170?,1.5wt%sulfuric acid of 10ml/g liquid to solid ratio,residue time of 40 min,the amount of toluene is 0.27mol/g biomass.An M-O-L acid(mineral acid,organic acid,and Lewis acid)-catalyzed integrated process for furfural production from corncob was proposed to improve corncob conversion and furfural selectivity.First,the co-catalysts of sulfuric acid and acetic acid were investigated for their impact on furfural production.Sulfuric acid as a pretreatment catalyst was mixed with corncob before the experiment.Acetic acid,which is a byproduct of hemicellulose hydrolysis,was fed together with steam.The results showed that the cooperation of sulfuric acid and acetic acid decreased the total acid consumption dramatically.FeCl3·6H2O was also investigated as a co-catalyst in an effort to enhance the conversion of xylose to furfural and decrease furfural degradation.The integrated catalytic process achieved the highest furfural yield of 68.04%through using of M-O-L acid under a reaction temperature of 180?,3v%acetic acid,4.0 wt.%sulfuric acid of 0.6 mL/g liquid to solid ratio,and 5 g FeCl3·6H2O per 100 g of biomass.There are much more cellulose in furfural residues and 5-HMF can be obtained from the residues by acid hydrolysis.In this article,the residues was pretreated by inoic liquid(BMIMCl)and the results show that the crystallinity of cellulose decreased from 18.4%to 8.5%under the pretreatment conditions of 100? and 120min.Many reaction factors were investigated,including reaction temperature and time,concentration of hydrochloric acid.And the highest yield of 5-HMF 51.78%was obtainted under the conditions of LiCl dosage of 0.95mmol/g material,130?,hydrochloric acid of 4wt%and residue time of 20 min.