Highly Conductive Structured Catalytic Reactors for One-Step Synthesis of Dimethyl Ether

Abstract

Several structured catalytic reactors for the direct synthesis of the DME reaction are compared with regard to catalyst hold-up, thermal conductivity, and volumetric productivity. Adherent and homogeneous catalyst layers were obtained by washcoating independent of the substrates’ shape and alloy. Moreover, the substrate nature (FeCrAl, brass, or aluminum) and shape (parallel cell monoliths and open foams) do not modify in great extent the CO conversion values and selectivity to the different compounds. This is reasonable since the catalytic phases are the same in all cases and the existence of mass and heat-transfer limitations was negligible in the experimental conditions studied. Structuring by washcoating exhibits less catalyst inventory per reactor volume than a packed-bed monolith. However, completely packing a monolith with powder catalyst produced a decrease in the CO conversion of around 25% with respect to the coated monolith. Moreover, by means of using the obtained highest catalyst hold-up by washcoating (0.33 gcat/cm 3 ) in a brass monolith and by increasing the reaction temperature, the temperature profiles are only slightly affected. This allows to work in an almost isothermal reactor with a volumetric productivity up to 0.20 L DME /h·cm 3 at 573 K.

Structured Reactors Based on 3D Fe/SiC Catalysts: Understanding the Effects of Mixing

“…3,4,6 Their use implies the efficient utilization of materials and energy, 7,8 as well as the reduction of toxic emissions and byproduct formation. 9,10 The most common structured reactors are those equipped with well-designed structured catalysts, such as honeycomb, corrugated sheet, gauze, foam, fiber, or wire mesh packing. In a different level of application, microchannel reactors are also structured reactors where the catalytic materials are usually impregnated on a metallic plate installed inside the channel.…”

“… 3 , 4 , 6 Their use implies the efficient utilization of materials and energy, 7 , 8 as well as the reduction of toxic emissions and byproduct formation. 9 , 10 …”

“…However, the structuring at the reactor level leads to the use of a regular catalyst structure with low pressure drops, larger surface areas for solid–fluid contact, and thinner boundary layers that enhance the mass and heat transfer and precise control of the flow dynamics . Therefore, structured catalysts and reactors are one of the successful tools for process intensification to contribute to the sustainable development of the chemical industry. , Numerous works in the literature illustrate the benefits that structured catalysts and reactors offer to process intensification. ,, Their use implies the efficient utilization of materials and energy, , as well as the reduction of toxic emissions and byproduct formation. , …”