蜡样芽孢杆菌降解山西浑源褐煤工艺条件的优化  

Optimization of Technological Conditions of Shanxi Hunyuan Lignite Degraded by Bacillus cereus

作　　者：胡雪华 刘向荣[1] 赵顺省[1] 杨再文[1] 杨征[1] HU Xuehua;LIU Xiangrong;ZHAO Shunsheng;YANG Zaiwen;YANG Zheng(College of Chemistry and Chemical Engineering,Xi’an University of Science and Technology,710054 Xi’an,China)

机构地区：[1]西安科技大学化学与化工学院,西安硕士生710054

出　　处：《煤炭转化》2019年第1期64-72,共9页Coal Conversion

基　　金：国家自然科学基金资助项目(21373158);陕西省科技厅中澳合作项目(2013KW17)

摘　　要：研究了蜡样芽孢杆菌对山西浑源褐煤的降解过程,通过单因素实验探索了煤浆质量浓度、煤氧化程度、接种量、培养方式和培养天数等因素对溶煤效果的影响。结果表明:各因素的最优水平为煤浆质量浓度0.60g(煤)∶50mL(培养基),硝酸与煤氧化比例15g(煤)∶50mL(硝酸),接种量4.0mL(菌液)∶50mL(培养基),培养温度30℃,摇床转速160r/min,培养时间31d,此时溶煤率达到34.45%。进一步通过正交实验优化培养条件,得到最优降解工艺条件为煤浆质量浓度0.50g(煤)∶50mL(培养基),接种量7.0mL(菌液)∶50mL(培养基),培养温度30℃,摇床转速160r/min,培养时间22d。在此条件下,溶煤率达到38.57%。利用元素分析、傅立叶红外光谱、X-射线衍射等手段对原煤、氧化煤和残煤进行了表征。结果表明:煤经硝酸氧化处理后,碳和氢含量减少,含氧量由20.49%(质量分数,下同)增加到27.87%,含氮量由1.68%增加到5.71%,氧化煤的晶核和缩聚程度下降;氧化煤中羧基和氨基的存在,增加了生物酶与氧化煤的作用位点,使煤中大分子结构被降解为低分子质量类物质。紫外-可见光谱和气相色谱-质谱联用分析表明,溶煤产物中含有大量长链脂肪族碳氢化合物、芳烃衍生物和酯类等物质。The degradation process of Hunyuan lignite in Shanxi by Bacillus cereus was studied.Through the single factor experiment,the effects of coal pulp mass concentration,oxidation degree of coal,inoculum amount,cultivation way and incubation time on the degree of biosolubilization were investigated.The optimal level of each factor is coal pulp mass concentration 0.60 g(coal)∶50 mL(culture medium),coal to HNO 3 ratio 15 g∶50 mL,inoculum amount 4.0 mL(bacterial solution)∶50 mL(culture medium),34.45%oxidized lignite is degraded for 31 d at 30℃and 160 r/min.Further orthogonal experiments were conducted to optimize the culture conditions,it shows that the best technological conditions is coal pulp mass concentration 0.50 g(coal)∶50 mL(culture medium),inoculation amount 7.0 mL(bacterial solution)∶50 mL(culture medium),38.57%oxidized lignite degraded at 30℃and 160 r/min for 22 d.Initial coal,oxidized coal and residual coal were characterized by ultimate analysis,Fourier transform infrared spectroscopy and X-ray diffraction.The results show that the contents of C and H decrease,the O content increases from 20.49%(mass fraction,the same below)to 27.87%,the N content increases from 1.68%to 5.71%,and the nucleation and polycondensation degree of oxidized coal decrease.The existence of carboxyl group and amino group in oxidized coal increases the interaction site between enzymes and oxidized coal,which makes the macromolecular structure of coal degraded into low molecular weight substances.Ultraviolet-visible spectroscopy and gas chromatography-mass spectrum show that coal-soluble products are long-chain aliphatic,aromatic hydrocarbon derivatives and esters substances.

关 键 词：浑源褐煤 蜡样芽孢杆菌 生物溶煤 工艺优化 产物表征 

分 类 号：TQ536.1[化学工程—煤化学工程]