本文選題：固定化 + DBP��； 參考：《東北農業(yè)大學》2015年碩士論文

【摘要】：土壤中酞酸酯(PAEs)污染來源十分廣泛,農膜殘留、農藥和肥料施用、生活垃圾以及污水灌溉等都能夠引起土壤PAEs污染。本研究運用固定化技術,對鄰苯二甲酸二丁酯(DBP)降解菌進行包埋,對制備的固定化微球的性能進行表征,以及固定化微球對土壤中DBP的去除效果和生態(tài)修復效應等多方面考察固定化微球的修復效果。以固定化微球對DBP的降解率為考察目標,優(yōu)化固定化成球條件。采用四因素三水平L9(34)的正交試驗,選擇不同的海藻酸鈉/膨潤土比例、Ca Cl2濃度、殼聚糖溶液濃度以及包菌量為組分。正交實驗的結果表明固定化成球的最佳條件為海藻酸鈉/膨潤土為2:1,殼聚糖濃度為0.5%,氯化鈣為1.5%,包菌量為10%。利用紅外光譜、掃描電鏡及比表面積分析儀等,對固定化微球進行性能表征。結果表明:膨潤土的表面存在大量的-OH,海藻酸納的羧基發(fā)生了離子化,海藻酸鈣凝膠與膨潤土之間形成了離子鍵,產生了微弱的靜電引力。膨潤土中的羥基,在水環(huán)境中與海藻酸鈉能夠產生氫鍵,從而限制了海藻酸鈣凝膠的溶脹。固定化微球的載體材料海藻酸鈉與膨潤土的比例為2:1時,其具有較大的比表面積和大量的微孔,能夠更好的實現菌體在其內部的存活以及對污染物DBP的有效降解�？疾旃潭ɑ⑶蛟�28 d內的實際修復效果以及特性。土壤修復過程中,14 d時,各處理組DBP殘留量均在66%以上;在28 d時,固定化微球處理組中,DBP的殘留量小于20%。固定化微球在三次重復使用后,對底物DBP的降解率仍然保持在20%以上。4℃條件下,28 d時,固定化微球處理組中,DBP的降解率為78.04%。采用PCR-DGGE技術考察修復后土壤微生物群落結構的變化情況,對DGGE凝膠上19個條帶切膠后進行克隆,經測序鑒定,同源性比較,鑒定結果證明試驗土壤中微生物主要分屬于放線菌門、厚壁菌門和變形桿菌門(α-變形菌綱、β-變形菌綱及γ-變形菌綱)3個大類。受DBP污染的土壤樣品和接種游離菌后微生物豐富度隨著時間的推移,并未發(fā)生較大的波動。固定化微球處理和游離菌處理的多樣性指數均呈現先上升后下降的趨勢,空白處理組的變化不明顯,在28d達到最高。各處理的微生物均勻度均沒有發(fā)生顯著性改變,其中空白處理微生物均勻度在后期呈現先下降的趨勢。不同形態(tài)降解菌的接種以及DBP的投加均改變了土壤微生物群落結構。利用氯仿熏蒸提取法測定固定化微球對DBP污染土壤中微生物生物量碳、氮、磷隨修復時間的動態(tài)變化。結果表明,修復過程中,固定化微球的加入可以有效的緩解DBP對土壤微生物活性的影響。研究表明,接種固定化微球能夠有效的修復DBP污染的土壤,降低DBP對土壤的危害,同時為土壤中有機污染物的去除提供一定的理論基礎以及技術支撐。
[Abstract]:Phthalic acid esters (PAEs) in soil are polluted from a wide range of sources, such as agricultural film residues, pesticide and fertilizer application, domestic waste and sewage irrigation can cause soil PAEs pollution. In this study, the immobilization technique was used to encapsulate the dibutyl phthalate (DBP) degrading bacteria, and the properties of the immobilized microspheres were characterized. The effects of immobilized microspheres on the removal of DBP and ecological remediation were investigated. The degradation rate of DBP by immobilized microspheres was taken as the objective to optimize the conditions of the immobilized microspheres. Four factors and three levels of L9 (34) orthogonal experiment were used to select different concentrations of sodium alginate / bentonite, concentration of chitosan solution and amount of bacteria. The results of orthogonal experiment showed that the optimum conditions for the formation of the pellets were as follows: sodium alginate / bentonite was 2: 1, chitosan concentration was 0.5, calcium chloride was 1.5 and the amount of bacteria was 100.The optimum conditions were as follows: (1) the concentration of sodium alginate / bentonite was 2: 1; The properties of the immobilized microspheres were characterized by IR, SEM and surface area analysis. The results show that there is a large amount of -OH on the surface of bentonite, the carboxyl group of sodium alginate is ionized, the ionic bond between calcium alginate gel and bentonite is formed, and the electrostatic force is weak. The hydroxyl group in bentonite and sodium alginate can form hydrogen bond in water environment, which limits the swelling of calcium alginate gel. When the ratio of sodium alginate to bentonite is 2:1, the carrier of immobilized microspheres has a large specific surface area and a large number of micropores, which can better realize the survival of bacteria in its interior and the effective degradation of pollutants DBP. The effect and characteristics of immobilized microspheres in 28 days were investigated. DBP residues in each treatment group were above 66% at 14 d during soil remediation, and less than 20% in immobilized microsphere treatment group at 28 d. After being reused for three times, the degradation rate of DBP in the immobilized microspheres was still above 20%, and the degradation rate of DBP in the immobilized microspheres group was 78.04 after 28 days. The changes of soil microbial community structure after restoration were investigated by PCR-DGGE technique. The 19 bands of DGGE gel were cloned and sequenced, and the homology was compared. The results showed that the microbes in the soil were mainly classified into three categories, namely Actinomycetes, Parthenomycetes and Proteus (偽 -Proteus, 尾 -Proteus and 緯 -Proteus). The soil samples contaminated by DBP and the microbial richness after inoculation of free bacteria did not fluctuate with time. The diversity index of immobilized microsphere treatment and free bacteria treatment increased first and then decreased, but the change of blank treatment group was not obvious and reached the highest level at 28 days. The microbial evenness of all treatments did not change significantly, and the microorganism evenness of blank treatment decreased first in the later stage. The structure of soil microbial community was changed by inoculation of different morphological degrading bacteria and addition of DBP. Chloroform fumigation extraction method was used to determine the dynamic changes of microbial biomass carbon, nitrogen and phosphorus in DBP contaminated soil with immobilized microspheres. The results showed that the effect of DBP on soil microbial activity could be effectively alleviated by immobilized microspheres during remediation. The results showed that inoculation with immobilized microspheres could effectively repair the soil contaminated by DBP, reduce the harm of DBP to soil, and provide some theoretical basis and technical support for the removal of organic pollutants in soil.
【學位授予單位】：東北農業(yè)大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：X53;X172

【參考文獻】

相關期刊論文 前8條

1 王紅芬;程晗煜;洪堅平;;環(huán)境中酞酸酯的污染現狀及防治措施[J];環(huán)境科學與管理;2010年07期

2 王平,王文斌,吳翔;特定環(huán)境下大氣顆粒物中酞酸酯的分析與研究[J];中國環(huán)境監(jiān)測;2005年04期

3 姜盛君;李存雄;張明時;;貴陽市水環(huán)境中6種酞酸酯類污染現狀研究[J];貴州師范大學學報(自然科學版);2010年01期

4 顏慧瓊;李嘉誠;馮玉紅;胡文濤;牛迪;林強;;膨潤土對海藻酸鈉/殼聚糖凝膠微球性能的影響[J];精細化工;2013年02期

5 姚健,楊永華,沈曉蓉,陸維忠;農用化學品污染對土壤微生物群落DNA序列多樣性影響研究[J];生態(tài)學報;2000年06期

6 張前龍,蔡智鳴,張欣文,王楓華,史馨,厲曙光;酞酸二丁酯對黑腹果蠅壽命及SOD和MDA的影響[J];同濟大學學報(醫(yī)學版);2005年04期

7 楊國義;張?zhí)毂?高淑濤;郭治興;萬洪富;羅薇;高原雪;;廣東省典型區(qū)域農業(yè)土壤中鄰苯二甲酸酯含量的分布特征[J];應用生態(tài)學報;2007年10期

8 金德才;梁任星;王洋洋;代沁蕓;張瑞永;吳學玲;;一株DBP高效降解菌的篩選及其降解特性[J];中南大學學報(自然科學版);2010年01期

相關博士學位論文 前1條

1 申為寶;蘋果園土壤生物活性及土壤鎘行為的生物調節(jié)[D];山東農業(yè)大學;2009年

相關碩士學位論文 前1條

1 陳俊蓉;毛竹林地覆蓋煙草秸稈分解層微生物特征研究[D];福建農林大學;2009年

，

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