从泥炭中提取腐殖酸的工艺及其结构研究

Study on the Extraction Technology and Structure of Humic Acid from Peat

探讨了不同预处理方法对从泥炭中提取腐殖酸效果的影响,同时也考察了碱提取液及其酸析液对提取结果的影响。结果表明,采用硝酸对试验样品进行预处理提取率最佳,通空气氧化和超声处理对提取率有益,但是提升效果不明显。碱溶分析表明,若投加0.1mol/L的Na4P2O4与碱液混合,腐殖酸的提取率会得到显著提升,且随着碱浓度的增大而增加,碱溶效果表现为:Na4P2O4+KOH>Na4P2O4+NaOH>KOH>NaOH>Na2CO3;酸析时,当CH+<2 mol/L时,HCl与H2SO4效果相当,且随着酸度的增加提取率增大,当C+>2 mol/L时,HCl优于稀HSO,这是由于硫酸将腐殖酸部分氧化,造成提取率降低。

The influences of different pretreatment methods on the extraction effect of humic acid from peat were discussed. And the influences of alkali extract and its acid eduction on the extraction results were investigated. The results indicated that the extraction rate of pretreating test samples with nitric acid was the best. The ventilation oxidation and ultrasonic pretreatments were beneficial to the extraction rate, but the increase effect was not obvious. The alkali dissolution analysis showed that the extraction rate of humie acid would be significantly enhanced and increased with the increase of alkali concentration when 0.1 mol/L of Na4P2O4 was added to mix alkali liquor. The alkali dissolution effects were as follows： Na4P2O4 ＋ KOH 〉 Na4P2O4 ＋ NaOH 〉 KOH 〉 NaOH 〉 Na2CO3. In acid eduction, HCI and H2SO4 could obtain the conformable effect and the extraction rate increased with the increase of acidity when CH^ ＋ was below 2 mol/L. When C H^ ＋ was over 2 moL/L, HC1 was better than H2SO4. The reason was the extraction rate decreased that caused by the oxidization of humie acid with sulfuric acid.