The use of modelling to understand the mechanism of hydrogen peroxide direct synthesis from batch, semibatch and continuous reactor points of view
The use of modelling to understand the mechanism of hydrogen peroxide direct synthesis from batch, semibatch and continuous reactor points of view
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使用建模从间歇式、半间歇式和连续反应器的角度理解过氧化氢直接合成的机理
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
P. Biasi
中科院分区：
文献类型：
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作者：
Nicola Gemo;T. Salmi;P. Biasi
以Pd/K2621为催化剂，在间歇、半间歇和滴流床三种不同的反应器中进行了过氧化氢直接合成的实验研究。从实验的角度来看，获得了很好的结果，获得了高的H_2O_2选择性，在间歇式反应器中短接触时间在90%左右，在半间歇式反应器中在60%左右，在TBR中在70%左右。反应器模型中包含了与公认的反应网络相适应的最简单的速率方程，该模型考虑了液体催化剂表面气液之间的传质阻力。通过直接合成实验估算了所有反应和反应器的相应阿累尼乌斯参数。模型显示了间歇式、半间歇式和滴流床(TBR)反应器之间的反应速率变化。结果表明，如何在连续操作中改进反应器的设置和反应性能，以及如何比较不同反应器和不同条件下的结果。对反应的敏感性分析使人们对反应速度有了新的了解。TBR显示了传质限制如何有助于将反应引向过氧化氢合成。值得注意的是，这些结果是在没有任何酸或卤离子的情况下获得的，即没有使用已知的用于直接合成过氧化氢的选择性促进剂，因此动力学不受促进剂的存在的影响。
Hydrogen peroxide direct synthesis was experimentally studied in three different reactors, namely the batch, semibatch and trickle bed reactors (TBR), using a new promising catalyst based on Pd/K2621. Excellent results were obtained from the experimental point of view, achieving high H2O2 selectivities, around 90% for a short contact time in the batch reactor, 60% in the semibatch reactor and 70% in the TBR. The simplest rate equations compatible with the acknowledged reaction network have been included in a reactor model, which accounts for mass transfer resistances between the gas and the liquid in the liquid–catalyst surface. The corresponding Arrhenius parameters were estimated from direct synthesis experiments for all the reactions and reactors. The models show how the reaction rates change among the batch, semibatch and trickle bed (TBR) reactors. The results suggest how to improve the reactor set-up and reaction performance in continuous operations and how to compare the results between the different reactors and conditions. The sensitivity analysis on the reaction allowed to gain new insights into the reaction rates. The TBR showed how the mass transfer limitations can help to direct the reaction towards the H2O2 synthesis. Remarkably, these results were achieved in the absence of any acids or halide ions, i.e. no known selectivity promoters for direct H2O2 synthesis were applied, thus the kinetics are not affected by the presence of promoters.
影响因子：
17.1
作者：
Sankar, Meenakshisundaram;He, Qian;Hutchings, Graham J.
通讯作者：
Hutchings, Graham J.