煤炭转化2024，Vol.47Issue(4)：32-42,11.DOI:10.19726/j.cnki.ebcc.202404004
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
摘要
Abstract
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 trans-form 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 spec-troscopy and infrared spectroscopy.The results of single-factor and Plackett-Burman experiments show that the pretreatment process parameters significantly affecting the extraction ratio of hu-mic acid from lignite are nitric acid concentration,degradation temperature and time.The opti-mal conditions for pretreatment of lignite by nitric acid oxidation coupled with biological degrada-tion,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 treat-ment,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Key words
lignite/Penicillium/humic acid/oxidation modification coupled with biodeg-radation/response surface分类
矿业与冶金引用本文复制引用
梁丹丹,梁海霞,崔丽萍,李佳勇,王双林,刘雨鹤,李欣欣..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[J].煤炭转化,2024,47(4):32-42,11.基金项目
山西省基础研究计划项目(202203021221046,202203021212197). （202203021221046,202203021212197）
