竹炭对生物油模型组分的吸附特性试验

Adsorption Properties of Model Component of Bio-oil from Aqueous Solution by Bamboo Charcoal

摘要:

以竹子为前躯体热解制得竹炭，选取糠醛、乙酸、苯酚、葡萄糖为生物油模型化合物，研究竹炭对生物油模型组成各单组分的静态吸附特性及双、四组分混合下的竞争吸附行为。结果表明：竹炭对不同组分的吸附特性存在较大差异；单组分吸附24h，竹炭对糠醛的吸附量最大，乙酸次之，对葡萄糖的吸附量最小；吸附平衡时，竹炭对苯酚的吸附量将超过乙酸；糠醛-葡萄糖双组分竞争下，竹炭对糠醛显示出强烈的选择性吸附特征；4种组分竞争下，各组分吸附量相对单组分均有所下降，其中乙酸降幅最大，且乙酸等物质在吸附过程中出现浓度突变现象，这可能是因为吸附性能较好的糠醛将已经吸附的乙酸从竹炭上置换下来；在选用的所有试验工况下，竹炭对葡萄糖均表现出低的吸附态势。

关键词:竹炭 生物油 模型组分 选择性吸附 竞争吸附 吸附特性

Abstract:

Bamboo charcoal obtained from pyrolysis was introduced as adsorbent to adsorb model compounds of bio-oil in solution. Single-, double- and four-component of bio-oil was investigated to evaluate the adsorption behavior. The results showed that the adsorption characteristics of each component were different. For single-component adsorption in 24h, the adsorption capacity of each component by bamboo charcoal in declining order was furfural, acetic acid, phenol and glucose. When adsorption equilibrium achieved, the adsorption capacity of phenol would exceed that of acetic acid. In double-component of furfural and glucose system, furfural was showed strongly selective adsorption characteristics by bamboo charcoal. In four-component system, the adsorption capacity of each component was declined especially for acetic acid. Further more, concentration mutation was presented among acetic acid and some component which suggested that the well adsorbed furfural displaced some of the weak adsorbate. The adsorption capacity of glucose was little under all the experimental operating conditions.

Key words:Bamboo charcoal Bio-oil Model component Selective adsorption Competitive adsorption Adsorption property