本文選題：玉米秸稈木質(zhì)素 + 漆酶　； 參考：《東北林業(yè)大學(xué)》2016年碩士論文

【摘要】：本文以漆酶和漆酶/介體體系在有氧條件下對玉米秸稈木質(zhì)素進行活化處理,選用了混合溶劑體系,有效解決了玉米秸稈木質(zhì)素難溶于水的問題,通過活化處理,提高了玉米秸稈木質(zhì)素的羥基含量,降低了其相對分子質(zhì)量,提高了反應(yīng)活性。(1)本文首先使用漆酶單獨活化處理玉米秸稈木質(zhì)素,選用了二氧六環(huán)/水、聚乙二醇/水、磺酸鹽木質(zhì)素/水三種溶劑體系,利用傅立葉變換紅外光譜(FT-IR)、紫外可見分光光度計、GPC和TGA進行微觀分析和表征,探究了處理時間(t)、體系pH值、處理溫度(T)和漆酶用量(漆酶酶活/木質(zhì)素質(zhì)量)對活化處理效果的影響,從而確定了適宜的活化處理條件為處理時間為1.5-2h,體系pH值為4.0-4.5,處理溫度為40℃,漆酶用量為25U/g。(2)用漆酶在三種體系對應(yīng)的最適活化處理條件下活化處理玉米秸稈木質(zhì)素,對比分析了三種混合溶劑中活化處理效果的優(yōu)劣程度,確定了最佳的混合溶劑體系為聚乙二醇/水混合溶劑,此體系下最佳的活化處理條件為處理時間1.5h,體系pH值為4.0,處理溫度為40℃,漆酶用量為25U/g,可將木質(zhì)素羥基含量由3.6%提升至4.3%,并利用DSC測試證明,活化后的玉米秸稈木質(zhì)素與飽和脂肪酸的酯化反應(yīng)能力提高。(3)選用了三種介體(HBT、紫丁香醛、香草醛),使用漆酶/介體體系在聚乙二醇/水混合溶劑體系中以最適宜處理條件對玉米秸稈木質(zhì)素進行活化處理,實驗證明,漆酶/介體體系活化處理可以進一步降解玉米秸稈木質(zhì)素,使高分子量木質(zhì)素發(fā)生斷鏈降解,其中漆酶/HBT介體體系活化處理玉米秸稈木質(zhì)素,可將木質(zhì)素羥基含量由3.6%提升至4.6%,高分子量木質(zhì)素含量進一步減少,與漆酶單獨活化處理的玉米秸稈木質(zhì)素相比,漆酶/HBT體系活化木質(zhì)素與飽和脂肪酸的酯化反應(yīng)能力進一步增強。
[Abstract]:In this paper, laccase and laccase / medium system were used to activate corn straw lignin under aerobic conditions, and mixed solvent system was used to effectively solve the insoluble water problem of corn stalk lignin. The hydroxyl content of corn straw lignin was increased, the relative molecular weight of lignin was decreased, and the reaction activity was improved. (1) in this paper, the lignin of corn straw was treated by laccase alone, dioxane / water, polyethylene glycol / water were selected. The sulfonate lignin / water system was characterized by Fourier transform infrared spectroscopy (FTIR), UV-Vis spectrophotometer and TGA. The treatment time and pH value of the system were investigated. The effects of temperature (T) and laccase dosage (laccase activity / lignin quality) on the activation treatment were determined. The optimum conditions of activation treatment were as follows: treatment time 1.5-2h, pH 4.0-4.5, treatment temperature 40 鈩，

本文編號：1857693