Charaterization And Application Of Lignin From Corn Stalk

With increasing environmental pollution and the severe depletion of energy resources,people began to look for environmentally and friendly biomass resources that can replace oil and other energy.Huge reserves of corn stalks,as a renewable agricultural waste,has been paid attention by people gradually.Extracted lignin from corn stalks is separated for the realization of cornstalks components efficient and value use separate foundation.We studied on the lignin(MWL)structure from corn stalks and using 1,4-butanediol separated lignin and optimize the process conditions.The separated lignin were used as a raw material for preparing a polyurethane films.We explored the impact from high boiling solvent lignin content and molecular weight of polyethylene glycol(PEG)to the polyurethane films performance and optimize the process conditionsAnalysis of lignin from corn stalks(MWL)by Infrared Spectroscopy(IR)indicate that lignin from corn stalks belongs GSH type of lignin.Throwing the alkaline nitrobenzene oxidation experimental data of corn stalks analysis,we can concluded that the jade radio of the guaiacol phenyl propane units and the ratio of hydroxy phenyl propane units and lilac benzene oxide units is about 7.5: 3: 4.The pyrolysis analysis of corn stalks MWL shows that corn stalks MWL has good thermal stability.Corn cob residual is a main by-product of agriculture in China,can be realized the fully utilization of all three components by exploring the lignin separation technology.High boiling solvent of 1,4-Butanediol was selected as cooking solvent to separate lignin from corn cob residual in this study.The optimal cooking conditions were:1,4-butanediol90%(mass fraction),cooking temperature160 oC,solid: liquid ratio1:10,time at maximum temperature 1.5h,dosage of concentrated sulfuric acid 0.15 mL/g(relative to the dry raw material).The highest lignin yield was 89.2%,which was equal to 18.2%.Additionally,the reduction of functional groups of lignin was not significantly verified by FTIR and UV,hence facilitating the downstream potential application.High boiling alcohol solvent(HBS)is the use characteristics of a high-boiling solvent such as high boiling point?low volatility and good solubility to the lignin,to extract and separate the lignin from the plant fiber raw materials.And we can obtain a higher extraction rate.The 1,4-butanediol can be recycled by rotary evaporation,so the reacted process is environment-friendly.This made it possible for efficient utilization of lignin foundation.We used the HBS lignin to prepare a polyurethane films and explored the impact of reaction include high boiling solvent lignin content and molecular weight of polyethylene glycol(PEG)to the performance of polyurethane films.We also optimize the the reaction conditions of the lignin-based polyurethane material.The study showed that: when the molecular weight of polyethylene glycol(PEG)is 400 and the mass fraction of high boiling solvent lignin is 12%,the polyurethane films had a good performance such as the tensile strength of the polyurethane films,the elastic modulus amount,an elongation,tear and water absorption were higher.The high boiling solvent lignin was added to the reaction instead of polyethylene glycol(PEG),this not only can effectively take advantage of the huge reserves of corn stalkst as raw material resources to reduce energy consumption,but can also reduce costs,which also provides an effective way on the high-value utilization of HBS lignin separation from cornstalk stalks.