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氧化预处理是褐煤制备腐植酸工艺中提高腐植酸产率的有效手段,以胜利褐煤为原料,腐植酸产率为目标值,考察了不同介质、氧化温度、H2O2质量分数及氧化时间等反应条件对氧化褐煤制备腐植酸产率的影响,对煤样和腐植酸产物进行了氧含量和含氧官能团的分析.结果表明,H2O2氧化褐煤可以明显促进腐植酸产率增加,H2O2和NaOH混合溶液对褐煤氧化时,腐植酸产率大于单一介质处理时的腐植酸产率;随着反应温度的升高,腐植酸产率逐渐增大;随着H2O2质量分数的升高,腐植酸的产率逐渐增加;随着氧化反应时间增大,腐植酸的产率在60 min时达到最大值.通过分析表明,氧化后腐植酸中氧质量分数明显增加,含氧官能团的种类没有明显变化,但是羧基和酚羟基质量分数分别增加了50.0％和33.7％.“,”Oxidation pretreatment plays an important role in improving the yield of humic acids trom lignite.Taking Shengli lignite as raw materials and the yield of humic acids as object value,the effects of different oxidizing mediums,oxidation temperature,mass concentration of H2O2 and oxidation time on the yield of humic acids from oxidation of lignite are studied.The oxygen content and oxygen-containing functional groups in both lignite samples and humic acids products are detected and analyzed.The results reveal that using H2O2 to oxidize lignite can significantly enhance the yield of humic acids;when the mixing solution of H2O2 and NaOH is used to oxidize lignite,the yield of humic acids is higher than that when single oxidizing medium is used;The yield of humic acids will increase with the increase of both oxidation temperature and H2O2 concentration;The yield of humic acids will increase with the extension of the oxidation time,and will reach the maximum value when the oxidation time reaches 60 min.The analysis results show that after oxidation,the mass content of oxygen in humic acids increases greatly and the categories of oxygen-containing functional groups have no significant changes,but the mass contents of carboxyl and phenolic hydroxyl groups increase by 50％ and 33.7％,respectively.