摘要
利用超声波、硝酸及超声波→硝酸3种方式分别对煤泥进行预处理,得到超声波预处理煤泥(CMN)、硝酸预处理煤泥(XMN)和超声波→硝酸预处理煤泥(CXMN),再采用苍白杆菌属对预处理前后的煤泥进行微生物降解,研究煤泥预处理方式对煤泥微生物降解过程的影响。实验结果表明:经过预处理的煤泥微生物降解效果均比未经预处理的煤泥(MN)微生物降解效果好,其中CXMN的降解率最高,为30.03%,超声波→硝酸预处理方式中超声波所用功率为200 W,时间为2 min,硝酸的浓度为8 mol/L;通过傅立叶红外光谱仪(FTIR)对原煤泥及不同预处理方式后的煤泥进行表征,发现经过预处理的煤泥芳香度、芳香环缩合度均降低,含氧官能团含量均增加,说明超声波和硝酸可以破坏煤泥中的芳香环结构、降低芳香环缩合度、增加煤泥表面含氧官能团含量;扫描电镜分析结果发现,CMN出现裂缝,XMN出现层状结构,CXMN呈粉末状,不同方式预处理后煤泥结构的改变有利于煤泥与微生物接触,从而提高煤泥的降解率;氮吸附分析结果发现,CMN与MN相比,孔径减小、孔体积增大、孔隙率增加,XMN孔体积和孔径较MN孔体积和孔径变化不大,CXMN孔体积和孔径较CMN孔体积和孔径均增大;采用气相色谱-质谱联用仪对不同预处理方式煤泥降解的液相产物进行表征,发现苍白杆菌属降解不同方式预处理后煤泥液相产物中的化合物组成相似,都包含烷烃类、酯类、醛酮类、羧酸类等物质。
The coal slime was pretreated by ultrasound,nitric acid and ultrasound→nitric acid methods to obtain ultrasound-pretreated coal slime(CMN),nitric acid-pretreated coal slime(XMN),and ultrasound→nitric acid-pretreated coal slime(CXMN).The pretreated coal slimes were then subjected to microbial degradation using Ochrobactrum sp.to investigate the effect of pretreatment on the microbial degradation process.The experimental results show that the pretreated coal slime has a better microbial degradation performance when compared with untreated coal slime(MN),and the degradation rate of CXMN is the highest at 30.03%.Meanwhile,the ultrasound power used is 200 W for 2 min,and the concentration of nitric acid is 8 mol/L.Characterization of the raw coal slime and coal slimes undergoing different pretreatment methods was performed by Fourier transform infrared spectroscopy(FTIR).It is found that the aromaticity and aromatic ring condensation degree decrease and the content of oxygen-containing functional groups increases for the pretreated coal slimes.indicating that ultrasound and nitric acid can disrupt the aromatic ring structure in the coal slime,reduce the degree of condensation,and increase the oxygen-containing functional groups on the surface of the coal slime.Scanning electron microscopy analysis reveals cracks in CMN,layered structures in XMN,and powdery CXMN.These structural changes were conducive to the contact between the coal slime and microorganisms,leading to increased degradation rates.The results of N_(2) adsorption analysis show that the pore size decreases and pore volume and porosity increase in CMN compared with MN.The pore volume and pore size of XMN do not change significantly compared with MN,whereas those of CXMN increase compared with CMN.The liquid products degraded by different pretreated methods were characterized by gas chromatography-mass spectrometry method,and the results show that the compounds in the liquid products of coal slime degraded by different pretreatment methods of compound are similar,such as alkanes,esters,aldehydes,ketones,and carboxylic acids.
作者
皇甫燕燕
刘向荣
石晨
杨再文
赵顺省
HUANGFU Yanyan;LIU Xiangrong;SHI Chen;YANG Zaiwen;ZHAO Shunsheng(College of Chemistry and Chemical Engineering,Xi’an University of Science and Technology,710054 Xi’an,China;Key Laboratory of Coal Resources Exploration and Comprehensive Utilisation,Ministry of Natural Resources,710021 Xi’an,China)
出处
《煤炭转化》
CAS
CSCD
北大核心
2023年第3期81-91,共11页
Coal Conversion
基金
国家自然科学基金资助项目(U1903133,21373158)
自然资源部煤炭资源勘查与综合利用重点实验室开放基金(KF2021-9)。
关键词
煤泥
苍白杆菌属
预处理方式
生物降解
降解率
coal slime
Ochrobactrum sp.
pretreatment method
biodegradation
degradation rate
