Study On The High Efficient Component Separation Of Corn Cob Based On Steam Explosion

Effective separation technology of the main component of lignocellulose is premise of agroforestry wastes transformation which is directional,high value,high efficiency and green.To establish the efficient separation technology system of the main component of corn cob,steam explosion was used as the core technology in this paper,and studied the effect of dilute sulfuric acid pretreatment,water content and added inorganic salt on separation of the main corn cob component by steam explosion.This had provided a feasible technical route for achieving a directed and high efficiency transformation of the components of corn cob.The main research contents and conclusions were as follows:(1)Using conditions of solid-liquid ratio 1:5,121? for 30 min studied the effect of 0-1.0%dilute sulfuric acid pretreatment on corn cob component separation by steam explosion.The results showed that 0.1%of dilute sulphuric acid pretreatment can significantly improve the effect of corn cob three element separation.After pretreatment of 0.1%dilute sulfuric acid and steam explosion,hemicellulose degradation rate and recovery rate of corn cob reached 83.02%and 82.64%,respectively,compared to the control group,they increased 20.7%and 20.7%respectively.The concentration of glucose and total sugar in enzyme hydrolysate of steam exploded corn cob residue reached 68.18 and 81.84 g/L respectively,increased by 22.6%and 18.71%respectively than control;cellulose recovery rate of corn cob and cellulose conversion rate of steam exploded residue reached 63.36%and 63.36%respectively,increased by 8.92%and 14.02%respectively than control.(3)Corn cob was infiltrated with a certain concentration of inorganic salt solution,such as Fe(NO3)3,FeCl3,NH4Cl,Fe2(SO4)3,NaCl,CaCl2 and(NH4)2C2O4,(adding 60 mL to per 100 g corn cob)before steam explosion which can significantly improve the effect of hemicellulose degradation of com cob by steam explosion.The cellulose degradation rate of corn cobs treated with Fe(NO3)3,FeCl3 and NaCl reached 94.61%,94.06%and 89.79%respectively,increased by 12.43%,11.78%and 6.7%respectively than control.Hemicellulose recovery was used as the evaluation standard,the optimum used concentration of Fe(NO3)3,FeCl3 and NaCl were studied,the results showed that NaCl and FeCl3 catalysis can significantly increase the hemicellulose and cellulose recovery rate of corn cob,when the concentration of NaCl and FeCl3 were 0.3 M and 0.05 M seperately,the hemicellulose recovery rate of corn cob reached as high as 96.9%,and 89.21%,45.96%,45.96%and higher than that of control group;at the same time,the cellulose conversion rate of steam exploded residue were 89.53%and 93.69%respectively,10.35%and 15.5%higher than that of control;and cellulose recovery rate of corn cob were 82.85%and 81.71%respectively,4.95%,3.5%and higher than that of control,while the Fe(NO3)3 catalysis was disadvantageous to the hemicellulose and cellulose recovery of corn cob.(4)With steam explosion technology used as the core,this paper optimized the conditions of dilute sulfuric acid pretreatment,water content and inorganic salt auxiliary of corn cob before steam explosion,compared to stem explosion alone,the hemicellulose degradation rate of corn cob was improved from 68.78%to 98.13%,the hemicellulose recovery rate of corn cob was improved from 56.74%to 96.9%,89.21%,and cellulose recovery rate of corn cob increased from 52.41%to 82.85%,83.02%,which eventually formed a set of engineering system for separating corn cob component effectively,as followed:...