【正文】 % and H2O2 concentration %. The conditions of precipitation lignin are pH≤, temperature ≥60℃. The extraction rate of lignin can reach 90% in accordance with higher purity. Especially, both hemicellulose and cellulose are little destroyed. Infrared spectrum characteristic analysis demonstrated that there were no cellulose and no linkedbond with hemicellulose in lignin Ⅰ, Ⅱ, Ⅲ and Ⅳ. Hemicellulose in lignin Ⅰwas pletely separated, while little hemicellulose could be absorbed in lignin Ⅱ, Ⅲ and Ⅳ. Lignin Ⅰ is a guajacylsyringylhydroxyphenyl lignin (GSH), and any of lignin Ⅱ, Ⅲ and Ⅳ is a guajacylsyringyl lignin (GS). Key word： Lignin。在上述條件下木質(zhì)素的提取率達(dá)到90%，且純度較高，對(duì)分級(jí)分離的附屬產(chǎn)品半纖維素和纖維素的破壞性較小。 畢 業(yè) 論 文題 目： 木質(zhì)素的分級(jí)分離及其性能研究 學(xué)院： 化學(xué)化工學(xué)院 專(zhuān)業(yè)： 生物工程 班級(jí)：0402 學(xué)號(hào)： 202206030207學(xué)生姓名： 劉 輝 導(dǎo)師姓名： 謝 濤 完成日期： 2022 年 6 月 14 日 目 錄中文摘要 .....................................................................................................................................IABSTRACT...............................................................................................................................II1 前言.......................................................................................................................................1 國(guó)內(nèi)外木質(zhì)素研究概況及其現(xiàn)狀...............................................................................1 木質(zhì)素的分離方法及其不足.......................................................................................1 本課題立題依據(jù)...........................................................................................................1 本課題研究目的.................................................................................................1 本課題主要研究任務(wù).........................................................................................22 實(shí)驗(yàn)材料與方法...................................................................................................................3 實(shí)驗(yàn)材料與儀器.........................................................................................................3 實(shí)驗(yàn)原料.............................................................................................................3 實(shí)驗(yàn)設(shè)備.............................................................................................................3 實(shí)驗(yàn)試劑.............................................................................................................3 實(shí)驗(yàn)方法.......................................................................................................................4 竹材成分測(cè)定.....................................................................................................4 堿性過(guò)氧化物法分離木質(zhì)素.............................................................................4 紅外光譜特征的測(cè)定.........................................................................................43 結(jié)果與分析...........................................................................................................................6 原料化學(xué)成分................................................................................................................6 工藝條件的優(yōu)化...........................................................................................................6 氫氧化鈉濃度對(duì)木質(zhì)素的影響.........................................................................6 雙氧水濃度對(duì)木質(zhì)素的影響.............................................................................7 溫度和反應(yīng)時(shí)間對(duì)木質(zhì)素的影響.....................................................................7 木質(zhì)素分級(jí)組分的得率與表觀特征.................................................................8 木質(zhì)素分級(jí)分離工藝對(duì)不同原料的適應(yīng)性.....................................................9 分級(jí)組分的紅外光譜特征.........................................................................................104 討論.....................................................................................................................................155 結(jié)論.....................................................................................................................................19參考文獻(xiàn)...................................................................................................................................20致 謝.........................................................................................................................................22附圖...........................................................................................................................................23 化學(xué)化工學(xué)院 08 屆本科畢業(yè)論文木質(zhì)素的分級(jí)分離及其性能研究摘要：以竹子、竹筍、竹筍殼為原料，對(duì)木質(zhì)素的分級(jí)分離工藝條件進(jìn)行了研究，并檢測(cè)了木質(zhì)素分級(jí)組分的紅外光譜特征。通過(guò)單因素實(shí)驗(yàn)確定