In Situ Measurement of Dissolved Hydrogen during the Liquid-Phase Hydrogenation of Dinitriles-Method and Case Study
In Situ Measurement of Dissolved Hydrogen during the Liquid-Phase Hydrogenation of Dinitriles-Method and Case Study
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二腈液相加氢过程中溶解氢的原位测量方法和案例研究
DOI：
10.1021/ie050612y
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
J. Lercher
中科院分区：
文献类型：
--
作者：
Peter Schärringer;T. Müller;W. Kaltner;J. Lercher
尽管气/液/固多相系统在工业规模的化学品生产中很重要，但测量溶解在液体中的气体浓度仍然是确定基本反应数据，如速率和吸附常数的先决条件，仍然具有挑战性。最近，一种新的渗透探头问世，它可以在线测量液体中的气体浓度。为了评估潜在的应用，该探针被用来跟踪钴催化的脂肪族二腈还原为相应的二胺过程中的溶解氢浓度。将反应过程中氢饱和度的变化与由Kla测量确定的反应器的气相−液(G−L)的传质特性相比较。在所用反应条件下，当搅拌速度降低时，G-−L传质成为决定反应速率的步骤。该渗透探头可用于直接评价G-−L传质的意义。
Despite the importance of gas/liquid/solid multiphase systems in the production of chemicals on an industrial scale, measuring the concentration of gases dissolved in the liquid phasea prerequisite for determining basic reaction data such as rate and adsorption constantsremains challenging. Recently, a new permeation probe became available, which allows in situ measurement of gas concentrations in liquids. To evaluate potential applications, the probe was used to follow the concentration of dissolved hydrogen during the cobalt-catalyzed reduction of an aliphatic dinitrile to the corresponding diamine. The changes in the hydrogen saturation level during the reaction were compared to the gas−liquid (G−L) mass transfer characteristics of the reactor as determined by kLa measurements. Under the reaction conditions used, G−L mass transfer became the rate-determining step when the stirring speed was decreased. The permeation probe allowed for evaluating the significance of G−L mass transfer in a straightforward...