| Agriculture is fundamental to humans to live.With the rapid development of agriculture,the problems that agricutural wastes bring about are more severe.At the same time,energy crisis needs to be urgently solved,which is also a key for rapid development of every country.The agriculture and forestry wastes belong to typical biomass energy which can be transformed from the low-grade and hard-to-use biomass into original chemical materials to replace petroleum base and the substitutions and then,be made into high-grade and high value-added base necessities for further processing,which canrelieve not only the environmental pressure brought by rapid agricultural development,but also energy crisis.This study aims to change traditional utilization models which are less environmentally friendly and have lower utilization rate.More specificly,the first objective was to liquefy wastes and make banana wastes be transformed into liquid active substances.Then,the available ways were investigated and finally,the performance of agriculture wastes based chemical productions was assayed.Composition analysis is the basis of comprehensive utilization.The banana wastes were fractionated into four morphological regions:leaf blades,leaf vein,petiole,floral stalk.Combining with recent perfect quantitative analysis to fibrous materials for index compositions,the four regions were quantitatively analyzed for moisture,ash,wax,water-soluble,pectin,hemicellulose,ligin and cellulose.Regarding to some problems of quantitative analysis,which were summaried and some methods were given.The results indicated that the banana wastes from Meian Town in Haikou contained high content of inorganic salt and the highest content for dried wastes was water-soluble.In addition,the index compositions still were made up of hemicellulose,ligin and cellulose.For the four regions,leaf blades had the hightes tcontent of ligin to get 27.91%,25.9%highest content of hemicelllulose for floral stalk,the content of cellulose can get 30.91%and 29.26%for leaf vein and petiole.Banana pseudo-stem occupied the largest proportion in different wastes.Therefore,this study chose it as the research objective,sulfuric acid as catalyst.Liquefaction of banana pseudo-stem in phenol was investigated.The results indicated that dosage of catalyst and reaction temperature were most significant on liquefaction and then,reaction time,the ratio of phenol to waste biomass subseqently.Considering all various factors,the optimal process was determined as catalyst(WH2SO4/W??)30%,temperature 160 ?,reaction time 40 min,ratio of phenol to raw material 4:1.Under this condition,the liquefaction ratio could reach 70.76%.The compositon analysis showed that liquefaction ratio could be attributed to ash content in raw material.Besides,there was a large amount of cellulose in the residue and there was a mass of phenolic hydroxyl groups in liquefaction products.Thus,it was stuitable for the preparation of epoxy adhesive.Purifying banana liquefaction products were determined as biobased-chemical-industrial product reacted with epichorohydrin at alkaline condition to prepare epoxy,which was interacted with polyamide-650 according to the different mixing ratio at different temperature,and the performance parameters of curied resin were tested.The results showed that banana pseudo-stem based epoxy resin had good adhesive property to different materials such as woody,aluminum and ironwork at different curing temperatures.When the mass ratio of synthetic epoxy resin and curing agent was 1:1 and the curing temperature was 100?,their tensile shear strengths could get 13.73 MPa for woody,14.03MPa for aluminum and 14.11MPa for ironwork,respectively.The glass transition temperature of curied resin could get 78 ? and it would rise with the increase of mass of epoxy resin.In addition,the banana pseudo-stem based epoxy adhesive had good resistance to acetone,methylbenzene,30%sudiom hydroxide solution and sulfuric acid solution.Replacing the phenol with original liquefied products absolutely to react with acetone at the present of catalyst concentrated sulfuric acid,and the impurities such as excess acid,acetone and slight water were removed.Then,the product removed impurities reacted with epichlorohydrin to prepare modified epoxy resin at alkaline condition.Comparing the previous resin,modified resin production was improved and it was more in line with the concept of green chemistry beceuse of recycle use of excess phenol.The results elucidated that modified resin was greater in transparency.However,the tensile shear strengths would decrease in large amplitude for woody material at the same curing condition.When mass ratio of catalyst and original liquefied product was 2:5,the tensile shear stengths could get 8.79MPa for aluminum and 14.63MPa for ironwork,respecitively.When mass of catalyst increased,for ironwork,the adhesive strength of modified resin would reduce 3.35MPa,while would increase 2.49MPa for aluminum. |
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