摘要
采用脉冲反应器 ,研究了 VPO催化剂的再生性质及其对晶格氧选择氧化丙烷制丙烯酸和乙酸的影响 .结果表明 ,VPO催化剂与气相分子氧反应的速度要比丙烷与其晶格氧反应的速度慢许多 ,因此以丙烷 - O2 共进料方式进行反应时 ,催化剂氧化再生是速度控制步骤 .水是影响催化剂选择性的重要因素 ,但对活性影响不大 .在反应温度下 ,水在 VPO催化剂上为可逆吸附 ,容易脱附流失 .催化丙烷反应生成目的产物的活性中心很稳定 。
Studies on the regeneration of vanadium phosphorous oxides(VPO) catalyst for selective oxidation of propane to acrylic acid and acetic acid has been carried out using a pulse reactor. The effects of regeneration time, H 2O content, and purging time on the catalyst performance were investigated. The results show that the re oxidation of VPO catalyst by gaseous phase O 2 is much slower than the oxidation of propane by the lattice oxygen of the catalyst. Therefore the regeneration of catalyst is the rate determining step for a steady state flow reaction. The water adsorbed on catalyst is very important to selectivity, but its effect on activity is quite small. At reaction temperature the adsorption of H 2O on VPO catalyst is reversible, so that the desorption of H 2O occurs quickly. It is also confirmed that propane reacts with lattice oxygen of VPO catalyst or oxygen strong adsorbed on it to form acrylic acid and acetic acid.
出处
《分子催化》
EI
CAS
CSCD
北大核心
2000年第1期11-14,共4页
Journal of Molecular Catalysis(China)
基金
国家自然科学基金资助课题 !(批准号:29676007)
关键词
VPO催化剂
再生
丙烷
晶格氧
氧化
催化剂
VPO catalyst
Regeneration
Propane
Lattice oxygen oxidation
Acrylic acid
