摘要
以竹粉为原料、CO_(2)为活化剂制备竹基多孔炭(ZH-100),并用于催化还原Cr(VI)。分析了反应温度、催化剂用量、还原剂甲酸用量、Cr(VI)初始质量浓度对竹基多孔炭催化活性的影响,采用XPS、XRD和交流阻抗测试技术对反应前后的多孔炭进行表征,以揭示其催化还原Cr(VI)的作用机制。结果表明:竹基多孔炭催化还原Cr(VI)的最佳实验条件为Cr(VI)初始质量浓度120 mg/L、温度60℃、ZH-100炭催化剂添加量0.1 g,还原剂甲酸添加量1.5 mL,在该条件下反应10 min,Cr(VI)还原率高达99.44%;重复使用3次后,ZH-100的催化还原能力略有下降,但仍能在30 min内达到99.22%的Cr(VI)还原率。分析发现,Cr(VI)的去除过程包括物理吸附和化学还原,其中以化学还原占主导;催化剂重复使用性能下降原因包括表面官能团消耗、碳微晶排列无序化及阻抗增大,ZH-100对Cr(VI)的催化还原机制为官能团介导和类石墨微晶介导。
Bamboo-based porous carbon(ZH-100)used for the catalytic reduction of Cr(VI)was prepared from bamboo powder and CO_(2)as an activator.The effects of reaction temperature,catalyst dosage of formic acid,reducing agent dosage,and initial mass concentration of Cr(VI)and other factors on the catalytic activity of bamboo-based porous carbon were investigated.The porous carbon was characterized by XPS,XRD,and alternating current impedance testing techniques to reveal its mechanism of action for the catalytic reduction of Cr(VI).The results showed that the optimum experimental conditions for the catalytic reduction of Cr(VI)by bamboo-based porous carbon were as follows:the initial concentration of Cr(VI)was 120 mg/L,the temperature was 60℃,the addition of ZH-100 carbon catalyst was 0.1 g,and the addition of reductant formic acid was 1.5 mL.Under these conditions,the reduction rate of Cr(VI)solution was up to 99.44%after 10 min of reaction.After three times of circulation,the catalytic reduction ability of ZH-100 decreased slightly,but the reduction rate was still able to achieve 99.22%reduction within 30 min.It was discovered that the removal of Cr(VI)involved physical adsorption and chemical reduction,with chemical reduction being the dominant process.The reasons for the decrease in catalyst performance after repeated use include the depletion of surface functional groups,the disorder of carbon microcrystals,and the increase of impedance.These indicated that the catalytic reduction mechanism of Cr(VI)by ZH-100 was functional group-mediated and graphite-like microcrystalmediated.
作者
连媛
王汉琛
方兆丰
何晨露
黄彪
林冠烽
LIAN Yuan;WANG Hanchen;FANG Zhaofeng;HE Chenlu;HUANG Biao;LIN Guanfeng(College of Material Engineering,Fujian Agriculture and Forestry University,Fuzhou 350002,China)
出处
《林产化学与工业》
CAS
CSCD
北大核心
2024年第3期61-68,共8页
Chemistry and Industry of Forest Products
基金
福建省科技创新重点项目(高校类)(2022G02004)
福建省科技计划项目(2022N5014)。
关键词
竹粉
竹基多孔炭
铬
催化
bamboo powder
bamboo-based porous carbon
chromium
catalysis
