A review on microreactors: Reactor fabrication, design, and cutting-edge applications

Mesoporous TiO2 supported Cu, Co, Ni, Pd, Sn and Zn catalysts (M-TiO2) were synthesized using facile one-step synthesis method and were characterized using BET, XRD, TGA-DSC, TEM, SEM-EDX, ICP-OES, and H2-TPR studies The catalysts were further tested for steam reforming of methanol (SRM) to investigate their comparative catalytic performance Depending on the nature of the metal component, the catalysts exhibited surface area, pore sizes, and TiO2 crystallite sizes in the range of 99–309 m2/g, 263–469 nm and 68–172 nm, respectively N2-physorption, TGA-DSC and XRD analysis demonstrated that the presence of metal in the TiO2 matrix stabilized the mesoporous structure by hindering the crystal growth during heat treatment and thereby preventing the collapse of porous structure Furthermore, the characterization of 5–20% Zn-TiO2 catalysts indicated that there exist an optimum Zn loading to obtain highest surface area which was found to be 15% in the present study giving a high surface area of ∼258 m2/g This was consistent with the SRM studies where the activity increased up to 15% and then decreased significantly with further increase in Zn loading to 20% The results of the SRM studies coupled with extensive TPR analysis of different M-TiO2 catalysts suggest that the specific metal-support interactions play a crucial role in controlling its performance on H2 production The SRM activity order for different metals incorporated in mesoporous TiO2 was observed to be: Pd > Ni > Zn > Co >> Cu >> Sn The Zn-TiO2 catalyst showed the lowest CO selectivity among the different catalysts studied

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Mesoporous nanocrystalline TiO2 supported metal (Cu, Co, Ni, Pd, Zn, and Sn) catalysts: Effect of metal-support interactions on steam reforming of methanol

Intensified catalytic reactors for Fischer-Tropsch synthesis and for reforming of renewable fuels to hydrogen and synthesis gas

Hydrogen production from ethanol steam reforming on M/CeO2/YSZ (M = Ru, Pd, Ag) nanocomposites

Rates and selectivities for the oxidation of various organosulfur compounds with tert-butyl hydroperox- ide were measured on CoAPO-5 (APO = aluminophosphate; Co/P = 0.05),Co/H-Y (Co/Al = 0.15),and MoOx/Al2O3 (15 % wt MoO3). Rates increased with increasing electron den- sity at the sulfur atom (methyl phenyl sulfide > diphenyl sulfide > 4-methyldi- benzothiophene > 2,5-dimethyl thio- phene). Rates (per metal atom) were significantly higher on CoAPO-5 than on Co/H-Y,MoO x/Al2O3,or homoge- neous Co acetate catalysts. Small amounts of sulfoxides (1-oxide) were detected on all catalysts at low reactant conversions,together with their corre- sponding sulfones; at higher conver- sions,only sulfones (1, 1-dioxide) were detected,indicating that the oxidation of sulfoxides is much faster than for or- ganosulfur reactants in the sequential oxidation pathways prevalent on these catalysts. Framework Co cations were not leached from CoAPO-5 during the oxidation of 4-methyldibenzothio- phene,but most exchanged Co cations in H-Y and > 20 % of Mo cations in MoOx/Al2O3 were extracted during these reactions. The fraction of redox- active Co cations in CoAPO-5 and Co/ H-Y was measured by reduction-oxi- dation cycles using H2 and O2 and by UV-visible spectroscopy. This fraction was much larger in CoAPO-5 (0.35) than in Co/H-Y (0.01),consistent with the higher oxidation rates measured on CoAPO-5 and with the involvement of redox-active species in kinetically-rele- vant steps in catalytic oxidation se- quences. Redox-active Co cations at framework positions within accessible channels are required for catalytic ac- tivity and structural stability during ox- idative desulfurization,whether hydro- peroxides are used as reactants or as intermediates (when O2 is used as the oxidant).

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Selective catalytic oxidation of organosulfur compounds with tert-butyl hydroperoxide.

CFD modeling of compact methanol reformer

https://iopscience.iop.org/article/10.1070/RCR4484/pdf

Microchannel systems for fine organic synthesis

‘Levitation’ of paramagnetic oxygen molecules over the surface of high temperature superconductors

Data on the effect of adsorption and intercalation of foreign molecules on the properties of high-temperature superconducting materials and on the reciprocal effect of superconductivity on the electronic state of adsorbed molecules are considered. Particular attention is given to the analysis of experimental conditions and interpretation of the results obtained. An effect of adsorbed molecules on the electrophysical state and the critical parameters of superconductors is noted. Specific features of the interaction between the phases in the superconducting state and the external molecules are discussed. The bibliography includes 280 references.

The chemical and adsorption effects of foreign molecules on the properties of high-temperature superconductors

The activity of Co/ZnO and Rh/Al2O3 catalysts in ethanol steam reforming was studied in a traditional tubular reactor with a fixed catalyst bed and in a microchannel reactor At temperatures of 600 and 700°C, the Rh/Al2O3 catalyst was much more active and stable than Co/ZnO A comparison between the reactors of two types showed that the ethanol steam reforming occurred more efficiently in the microchannel reactor because of intense heat and mass exchange The specific hydrogen production per unit weight of catalyst in the microchannel reactor was almost twice as high as that in the traditional reactor

L. L. Makarshin

Papers

CFD modeling of compact methanol reformer

Microchannel systems for fine organic synthesis

‘Levitation’ of paramagnetic oxygen molecules over the surface of high temperature superconductors

The chemical and adsorption effects of foreign molecules on the properties of high-temperature superconductors

Ethanol steam reforming over Co/ZnO and Rh/Al2O3 catalysts in a microchannel catalytic reactor