林业工程学报2025，Vol.10Issue(5)：75-81,7.DOI:10.13360/j.issn.2096-1359.202501024
活性炭制备过程中磷酸浸渍木材的形态结构
Investigation of morphological and structural changes in wood impregnated with phosphoric acid during activated carbon preparation
摘要
Abstract
The phosphoric acid activation method is a widely used approach for producing activated carbon from lignocellulose materials.During phosphoric acid activation,the impregnation of lignocellulose raw materials with phosphoric acid solution is a critical step that influences the pore structure of the resulting activated carbon.In this study,Chinese fir wood was used as the starting material.Field emission scanning electron microscope(SEM)and energy dispersive spectrometer(EDS)were used to observe changes in morphology and phosphoric acid distribution in the cross and tangential sections of the wood over varying impregnation durations.Nitrogen gas adsorption was employed to evaluate the pore structure of the activated carbons prepared under various impregnation durations.The results showed that the change in the morphology and anatomic structure of wood experienced three distinct stages in the impregnation process of wood with phosphoric acid solution.In the first stage(the impregnation time was 0-6 h),the phosphoric acid solution rapidly diffused into the interior of the wood,causing it to be evenly dispersed on the wood.In the second stage,the incorporated phosphoric acid into the wood predominantly gave a rise to the swelling-up of wood cell walls and the catalytical hydrolysis of polysaccharides.This led to significant thickening of the wood cell walls and striated walls,accompanied by the formation of a large amount of gel degradation products.During the first stage and the second stage(the impregnation time was 6-12 h),extending impregnation time significantly increased the specific surface area,micropore volume,and mesopore volume of the obtained activated carbon,with particularly notable development in the micropore structure.When the impregnation time reached 12 h,the specific surface area of activated carbon was 1 473 m2/g,the micropore volume was 0.520 cm3/g,and the mesopore volume of activated carbon was 0.620 cm3/g.In the third stage(the impregnation time was 12-24 h),continuous shrinkage and significant deformation of the wood tissue structure occurred due to the progressive action of phosphoric acid.At this stage,the specific surface area and pore volume of the activated carbon decreased with extended impregnation times,with mesopores exhibiting a more pronounced deterioration.These findings demonstrated that the phosphoric acid impregnation time,as a key factor in the activation process,will cause changes in the surface morphology of the raw materials and the distribution state of phosphoric acid,thereby significantly affecting the development of the pore structure of activated carbon.关键词
活性炭/磷酸活化/浸渍/木材/形态结构Key words
activated carbon/phosphoric acid activation/impregnation/wood/morphology分类
化学化工引用本文复制引用
李冰颍,左宋林,王珊珊,胡蒋根..活性炭制备过程中磷酸浸渍木材的形态结构[J].林业工程学报,2025,10(5):75-81,7.基金项目
国家重点研发计划(2023YFD2201601). （2023YFD2201601）
