摘 要
玉米秸稈作為天然的溢油吸附劑，其吸油量為4.9-6.2 g原油/g溢油吸附劑，可通過真菌改性提高其吸油量。作者以玉米秸稈作為黑曲霉固體發(fā)酵培養(yǎng)基的基質(zhì)，利用黑曲霉在生長過程中產(chǎn)生的菌絲機械穿插作用，增加玉米秸稈的孔隙，同時黑曲霉代謝分泌木質(zhì)纖維素酶，由內(nèi)向外降解木質(zhì)纖維素，使比表面積增大，達到對玉米秸稈改性的效果。
作者對黑曲霉改性玉米秸稈制備溢油吸附劑的反應(yīng)條件（溫度、反應(yīng)時間、含水率和菌體投加量）及機理進行了初步的探討。
結(jié)果表明：通過L25(56)4因素5水平的正交實驗得出，在無外加碳源的情況下，黑曲霉改性玉米秸稈制備吸附劑的條件的最優(yōu)組合是：菌體投加量為2 %、干料：水為1：3，反應(yīng)溫度為25℃，反應(yīng)時間為12d；影響程度為反應(yīng)時間>反應(yīng)溫度>(干料：水)>菌液投加量。在菌體投加量為2 %，干料：水為1：3的條件下，于30℃培養(yǎng)9d，吸油量達到最大值，是玉米原材料的2.8倍。在外加碳源（蔗糖），投加量為2%的情況下，最佳的反應(yīng)時間為6d，最佳含水率為1：3、最佳溫度為35℃，其最大吸油量是玉米秸稈原材料的2.9倍。外加碳源使吸油量最大值到來時間提前，吸油量增大。研究表明當酶活作用在一定時間和一定量的情況下，能使溢油吸附劑結(jié)構(gòu)孔隙率較高且持油性強，達到吸油量的最大值。BET、XRD、掃描電鏡和紅外光譜的表征結(jié)果分別顯示經(jīng)過黑曲霉改性后溢油吸附劑比表面積增大，結(jié)晶度上升，孔隙增多，但表面集團的種類沒有發(fā)生變化。

關(guān)鍵字：黑曲霉；玉米秸稈；溢油吸附劑；吸油量；酶活









Abstract
As natural sorbents in oil spill cleanup, the amount of oil sorbed by the corn stalk is
4.9-6.2 g crude oil/g sorbents, which can be improved by fungus modification. The author make corn stalk as the substrate of Aspergillus niger solid fermentation medium, taking advantage of the enzymes for lignocellulose degration secreted during Aspergillus niger‘s metabolism . Åt the same time, Aspergillus niger can reach the effect of modifying corn stalks because they are filamentous and have the ability to produce prolific spores to increase the specific surface area.
Preliminary study on the optimization (temperature, reaction time, water ratio and biomass dosage) and the mechanism of corn stalks modified by Aspergillus niger to make oil spill cleanup sorbents have been finished by author.
The results showed that: In the L25(56) orthogonal test(4 factors and 5 level) ,without external carbon source, the optimal combination of Aspergillus niger modifing corn stalks to make oil spill cleanup sorbents is: 12d reaction time, 25 ℃ reaction temperature , drier: water= 1:3(water ratio), 2% biomass dosage. The level of influence is time> the reaction temperature > water ratio > bacterium dosage. In the condition of 2% biomass dosage , drier:water= 1:3(water ratio), 30 ℃ and the reaction time is 9d, oil absorption reached maximum,which is 2.8 times than the raw corn stalk. With external carbon source, the optimization is 6d reaction time, 35 ℃ reaction temperature, drier: water= 1:3(water ratio) with 2% biomass dosage . The amount of oil sorbed by the oil spill cleanup sorbents is 2.9 times than the raw corn stalks.The study have showed that external carbon source can make the maximum of oil absorptivity not only came ealier, but also higher .Study shows that the enzymes for lignocellulose degration militate in a certain amount for certain reaction time can make the oil spill cleanup sorbents have higher multiaperture oil absorbent structure and the stronger ability to hold oil. In this way ,the amount of oill sorbed reach a satisfied value.The result of BET, XRD, SEM and FTIR spectra characterization show that the oil spill cleanup sorbents modified by Aspergillus niger have
larger surface area ,bigger crystallinity and more pores than the raw corn stalk, separately. However, the chemical grounps of the sorbents’ surface are unchanged.
Keyword: Aspergillus niger, corn stalk, oil spill cleanup sorbents, the amount of oil sorbed, enzyme activity


目 錄
摘 要 I
Abstract II

第一章 緒論 1
1.1溢油吸附劑 1
1.2溢油吸附劑的研究現(xiàn)狀 1
1.3真菌改性天然溢油吸附劑 4
1.3 .1玉米秸稈結(jié)構(gòu)及木質(zhì)纖維素組成及特點 4
1.3.2生物酶 6
1.3.3固態(tài)發(fā)酵 8
1.3.4真菌改性天然吸附材料的機理與特點 8
1.4研究目的及意義 9
1.4.1研究目的 9
1.4.2研究意義 9
1.5主要研究內(nèi)容 10

第二章 材料與方法 11
2.1 實驗材料 11
2.1.1供試菌種 11
2.1.2供試玉米秸稈 11
2.1.3供試原油 11
2.1.4培養(yǎng)基 11
2.1.5 固態(tài)發(fā)酵營養(yǎng)液 13
2.1.6主要儀器及設(shè)備 13
2.1.7主要試劑 14
2.1.8試劑配制 16
2.2研究內(nèi)容與方法 18
2.2.1無外加碳源情況下，黑曲霉改性玉米秸稈的條件研究 18
2.2.2外加碳源情況下，黑曲霉改性玉米秸稈的條件研究 20
2.2.3黑曲霉改性玉米秸稈的步驟 20
2.2.4木質(zhì)纖維素酶的酶活變化的測定 21
2.2.5木質(zhì)纖維素含量的測定 23
2.2.6吸油實驗步驟 23
2.2.7溢油吸附劑的表征方法 24

第三章 結(jié)果與討論 26
3.1標準曲線的繪制 26
3.1.1葡萄糖標準曲線（DNS光度法）的繪制 26
3.1.2木糖標準曲線（地衣酚光度法）的繪制 26
3.1.3葡萄糖標準曲線（蒽酮光度法）的繪制 27
3.2黑曲霉改性前玉米秸稈吸油情況 28
3.3無外加碳源情況下，黑曲霉改性玉米秸稈的條件研究分析 28
3.3.1無外加碳源情況..