竹炭表面结构及其对糠醛的吸附特性

Surface structure of bamboo charcoal and its adsorption property on furfural

为了去除生物油中的糠醛,该研究利用竹子为前躯体热解制得竹炭,选取糠醛为生物油模型化合物,在深入分析测试竹炭表面特性的基础上,研究竹炭对糠醛的静态吸附特性,并利用Langmuir和Freundlich等温吸附方程对试验数据进行拟合。结果表明以微孔为主的竹炭表面含有多种含氧官能团,如羟基、羧基等,同时还含有芳香族、脂肪族结构,这些表面官能团主要呈碱性;竹炭对糠醛具有较好的吸附脱除效果,25℃下,在糠醛浓度为10g/L,竹炭添加量为200g/L时,脱除率可达95%以上;其对糠醛的吸附主要依靠色散力作用;Freundlich等温吸附方程能更好地描述竹炭对糠醛的吸附特性。该研究有助于探索廉价的生物油除杂以适应糖发酵的新方法。

To remove furfural in bio-oil, bamboo charcoal obtained by pyrolysis was introduced as adsorbent. The structure property of bamboo charcoal was measured, and the adsorption property was investigated by Langmuir and Freundlich isothermal adsorption equation. The results showed that the bamboo charcoal dominant with micropore contained various alkali oxygen-functional groups （such as -OH, -COOH）, aromatic compounds and aliphatic compounds. Bamboo charcoal exhibited high adsorption capacity and removing efficiency, and the removing rate was over 95% with 10 g/L furfural and 200 g/L adsorbent dose at normal temperature. The adsorption was mainly attributed to the dispersion force. The adsorption process could be described with Freundlich isothermal adsorption equation. This research provides a new economic way for the high quality utilization ofbio-oil.