基于响应面法的硝酸氧化耦合生物降解预处理褐煤提取腐植酸工艺条件优化研究  

Optimization of nitric acid oxidation coupled with biodegradation condition for enhancing humic acid extraction from lignite based on response surface methodology

作　　者：梁丹丹 梁海霞 崔丽萍 李佳勇 王双林 刘雨鹤 李欣欣 LIANG Dandan;LIANG Haixia;CUI Liping;LI Jiayong;WANG Shuanglin;LIU Yuhe;LI Xinxin(College of Environmental Science and Engineering,Taiyuan University of Technology,030600 Jinzhong,China;College of Biomedical Engineering,Taiyuan University of Technology,030600 Jinzhong,China;College of Ecology,Taiyuan University of Technology,030600 Jinzhong,China;Shanxi Xinhua Chemical Defense Equipment Research Institute Company Limited,030008 Taiyuan,China)

机构地区：[1]太原理工大学环境科学与工程学院,山西晋中030600 [2]太原理工大学生物医学工程学院,山西晋中030600 [3]太原理工大学生态学学院,山西晋中030600 [4]山西新华防化装备研究院有限公司,太原030008

出　　处：《煤炭转化》2024年第4期32-42,共11页Coal Conversion

基　　金：山西省基础研究计划项目(202203021221046,202203021212197)。

摘　　要：从褐煤中提取腐植酸是实现低阶煤高值利用的有效途径,为提高矿源腐植酸提取率和生物活性,采用青霉菌(Penicillium pimiteouiense PPLL2205)高效降解转化褐煤,探究硝酸氧化耦合生物降解预处理对煤基腐植酸提取率的影响,结合元素分析、紫外-可见光谱和红外光谱分析表征其生物活性官能团。结果表明:经单因素和Plackett-Burman实验筛选得到显著影响褐煤腐植酸提取率的因素为硝酸浓度、降解温度和时间;通过Box-Behnken实验优化得硝酸氧化耦合生物降解预处理褐煤的最佳工艺条件为用5 mol/L硝酸氧化粒度为0.125 mm的褐煤,将氧化煤按1 g∶100 mL的固液比装载于接种有1.5%PPLL2205菌株的培养液中,调节pH为7,在温度为30℃、转速为230 r/min下降解15 d,再经碱溶酸提,此条件下腐植酸的提取率高达87.162%;与仅用硝酸氧化处理相比,硝酸氧化耦合生物降解预处理褐煤后提取的腐植酸含有更多的含氧官能团,具有更低的芳香度和更小的相对分子质量,在提高产率的同时增强了矿源腐植酸的生物活性。Extraction of humic acid from lignite is an effective way to achieve the high-value utilization of low-rank coal.To enhance the extraction ratio and bioactivity of coal-derived humic acid,Penicillium pimiteouiense PPLL2205 was employed to efficiently degrade and transform lignite,and the effect of nitric acid oxidation coupled with biodegradation pretreatment on the extraction ratio of coal-derived humic acid was investigated.The bioactive functional groups of the extracted humic acid were characterized by combining ultimate analysis,UV-visible spectroscopy and infrared spectroscopy.The results of single-factor and Plackett-Burman experiments show that the pretreatment process parameters significantly affecting the extraction ratio of humic acid from lignite are nitric acid concentration,degradation temperature and time.The optimal conditions for pretreatment of lignite by nitric acid oxidation coupled with biological degradation,determined via the Box-Behnken experiment,are as follows:lignite with particle size 0.125 mm,oxidation with 5 mol/L nitric acid,coal loading at a solid-to-liquid ratio of 1 g∶100 mL in a culture medium containing 1.5% PPLL2205,pH adjusted to 7,fungal degradation at 30 ℃ with a rotation speed of 230 r/min for 15 d.Under these conditions,the humic acid yield is 87.162% following alkali extraction and acid precipitation.Compared with the nitric acid oxidation treatment,the humic acid extracted by this pretreatment method contains more oxygen functional group,lower aromaticity and smaller molecular weight.These changes not only improved its yield but also enhanced the biological activity.

关 键 词：褐煤 青霉菌 腐植酸 氧化改性耦合生物降解 响应面 

分 类 号：TD849.2[矿业工程—煤矿开采]