【摘要】：預(yù)處理是木質(zhì)纖維素制備燃料乙醇的關(guān)鍵工序之一,因為木質(zhì)纖維素原料不能直接水解,它需要通過預(yù)處理的工序來破壞其物理化學(xué)結(jié)構(gòu),促進(jìn)其水解。60Coγ輻照是一種高效環(huán)保的預(yù)處理方法,它能打破木質(zhì)纖維素結(jié)構(gòu),促使纖維素酶有效酶解纖維素,提高乙醇轉(zhuǎn)化率。但同時60Coγ輻照會使木質(zhì)纖維素原料產(chǎn)生一些發(fā)酵抑制物。本文建立了高效液相色譜同時檢測三類主要抑制物(香草醛、香草酸、對羥基苯甲酸、4-羥基苯甲醛、對香豆酸、丁香酸等苯系化合物、糠醛等呋喃衍生物以及甲酸、乙酸等有機酸)的方法,并對60Coy輻照處理芒草、蘆葦及油菜秸稈中的發(fā)酵抑制物進(jìn)行了定量分析,研究了三種木質(zhì)纖維素原料在0～1200kGy輻照處理后的發(fā)酵抑制物含量變化規(guī)律,并選用1200kGy輻照的芒草進(jìn)行Ca(OH)_2過堿化脫毒處理和活性炭吸附脫毒處理,研究脫毒處理對發(fā)酵抑制物的脫除效果及其對安琪酵母發(fā)酵產(chǎn)乙醇的影響。主要研究結(jié)果如下：1、根據(jù)上述九種目標(biāo)發(fā)酵抑制物的性質(zhì),對液相色譜中檢測波長、流動相(種類、pH、緩沖鹽)、流速、柱溫以及洗脫梯度進(jìn)行優(yōu)化,試驗結(jié)果表明,采用C18色譜柱,柱溫25℃,乙腈-0.01mol(NH4)2HPO4(磷酸調(diào)節(jié)pH至2.7)為流動相,梯度洗脫,流速為0.8mL/min,多波長紫外檢測,可實現(xiàn)目標(biāo)化合物的有效分離和測定。九種目標(biāo)化合物的線性回歸方程相關(guān)系數(shù)為0.9995-1.0000,加標(biāo)回收率均在96%以上,相對標(biāo)準(zhǔn)偏差為1.5%-2.3%,最低檢出限為0.1-0.89 mg/L,滿足定量分析的要求。2、對0～1200kGy輻照處理后的芒草、蘆葦和油菜秸稈三種木質(zhì)纖維素原料水提液進(jìn)行檢測發(fā)現(xiàn),三大類抑制物的含量比例從高到低依次為：有機酸(甲酸、乙酸)、苯系化合物、呋喃衍生物(糠醛)；各發(fā)酵抑制物含量隨著輻照劑量的增大而增大。其中,輻照處理蘆葦中苯系化合物的含量最高,在1200kGy時達(dá)149.38mg/L；油菜秸稈中有機酸的總含量最高,在1000kGy時達(dá)600mg/L。3、選用1200kGy輻照的芒草進(jìn)行脫毒處理,結(jié)果表明：Ca(OH)_2過堿化脫毒處理可除去部分抑制物,而活性炭吸附法能脫除大部分抑制物,但是活性炭的吸附作用導(dǎo)致可發(fā)酵糖的損失也比較大,損失量達(dá)30%。將脫毒后的原料與未脫毒的進(jìn)行對照發(fā)酵試驗發(fā)現(xiàn),經(jīng)過發(fā)酵24h后,過堿化處理輻照芒草發(fā)酵生成的乙醇濃度為3.22g/L,活性炭吸附的輻照芒草發(fā)酵生成的乙醇濃度為3.44g/L,而未脫毒的輻照芒草發(fā)酵生成的乙醇濃度為3.50g/L。
[Abstract]:Pretreatment is one of the key processes in the preparation of fuel ethanol from lignocellulose, because lignocellulose raw materials can not be hydrolyzed directly, it needs to destroy its physicochemical structure through the pretreatment process. 60Co gamma irradiation is an efficient and environmentally friendly pretreatment method, which can break the structure of lignocellulose, promote cellulase to hydrolyze cellulose effectively and increase the conversion of ethanol. But at the same time, 60 Co 緯 irradiation will make lignocellulose raw materials produce some fermentation inhibitors. A high performance liquid chromatography (HPLC) method for the simultaneous determination of three main inhibitors (vanillin, vanillic acid, p-hydroxybenzoic acid, 4-hydroxybenzaldehyde, p-coumaric acid, eugenic acid, furfural and formic acid) was established. The fermentation inhibitors in mango grass, Reed and rape straw treated by 60Coy irradiation were quantitatively analyzed, and the contents of fermentation inhibitors of three lignocellulose raw materials treated with 0~1200kGy irradiation were studied. The 1200kGy irradiated mango grass was used for Ca (OH) _ 2 superalkalination detoxification and activated carbon adsorption detoxification to study the removal effect of detoxification treatment on fermentation inhibitor and its effect on ethanol production by An Qi yeast. The main results are as follows: 1. According to the properties of the above nine target fermentation inhibitors, the detection wavelength, mobile phase (type, pH, buffer salt), flow rate, column temperature and eluting gradient in liquid chromatography were optimized. Using C18 column, column temperature 25 鈩，

本文編號：2485620