A micropacked-bed multi-reactor system with in situ raman analysis for catalyst evaluation

Cao, Enhong; Brett, Gemma Louise; Miedziak, Peter J.; Douthwaite, Mark; Barrass, Simon; McMillan, Paul F.; Hutchings, Graham J.; Gavriilidis, Asterios

doi:10.1016/j.cattod.2016.06.007

Cited by 15 publications

(9 citation statements)

References 36 publications

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“…Despite the excellent catalytic activities reported for the above-mentioned bimetallic systems, Pd based nanoparticles have undoubtedly exhibited the best overall catalytic performance for the hydrogenation of 4-NP [24]. Previous studies showed that Pd-based bimetallic NPs are more effective than Pt-Au bimetallic NPs [25][26][27][28][29]. Alloying of Au-Pd results in modifying electronic and surface properties and in turn the adsorption and activation for substrates and thus yielding relatively faster reaction rate constants compared to Au-Pt alloys [25].…”

Section: Phil Trans R Soc Amentioning

confidence: 99%

Optimization of sol-immobilized bimetallic Au–Pd/TiO ₂ catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

Alshammari

Niu

Palmer

et al. 2020

Phil. Trans. R. Soc. A.

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A sol-immobilization method is used to synthesize a series of highly active and stable Au x Pd 1− x /TiO 2 catalysts (where x = 0, 0.13, 0.25, 0.5, 0.75, 0.87 and 1) for wastewater remediation. The catalytic performance of the materials was evaluated for the catalytic reduction of 4-nitrophenol, a model wastewater contaminant, using NaBH 4 as the reducing agent under mild reaction conditions. Reaction parameters such as substrate/metal and substrate/reducing agent molar ratios, reaction temperature and stirring rate were investigated. Structure-activity correlations were studied using a number of complementary techniques including X-ray powder diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. The sol-immobilization route provides very small Au–Pd alloyed nanoparticles, with the highest catalytic performance shown by the Au 0.5 Pd 0.5 /TiO 2 catalyst. This article is part of a discussion meeting issue ‘Science to enable the circular economy’.

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Section: Phil Trans R Soc Amentioning

confidence: 99%

Optimization of sol-immobilized bimetallic Au–Pd/TiO ₂ catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

Alshammari

Niu

Palmer

et al. 2020

Phil. Trans. R. Soc. A.

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“…Because of reduced length scales, they can offer advantages such as improved temperature control, accelerated heat and mass transfer, and enhanced mixing of reactants. 1 , 2 Micropacked bed reactors (MPBRs) or microfixed bed reactors, which combine the benefits of microreactors and fixed-bed reactors, have been demonstrated to be promising tools for multiphase catalytic reaction systems in investigating catalyst performance, 3 − 6 reaction kinetics, 7 and chemical synthesis. 8 − 11 Enhanced mass transfer in MPBRs has been reported by many researchers (refer to the review by Zhang et al 12 ).…”

Section: Introductionmentioning

confidence: 99%

Study of Liquid–Solid Mass Transfer and Hydrodynamics in Micropacked Bed with Gas–Liquid Flow

Cao

Radhakrishnan

Hasanudin

et al. 2021

Ind. Eng. Chem. Res.

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The volumetric liquid–solid (L-S) mass transfer coefficient under gas–liquid (G-L) two-phase flow in a silicon-chip-based micropacked bed reactor (MPBR) was studied using the copper dissolution method and was related to the reactor hydrodynamic behavior. Using a high-speed camera and a robust computational image analysis method that selectively analyzed the bed voidage around the copper particles, the observed hydrodynamics were directly related to the L-S mass transfer rates in the MPBR. This hydrodynamic study revealed different pulsing structures inside the packed copper bed depending on the flow patterns established preceding the packed bed upon increasing gas velocity. A “liquid-dominated slug” flow regime was associated with an upstream slug flow feed. A “sparse slug” flow regime developed with an upstream slug-annular flow feed. At higher gas velocity, a “gas continuous with pulsing” regime developed with an annular flow feed, which had similar features to the pulsing flow in macroscale packed beds, but it was sensitive and easily destabilized by disturbances from upstream or downstream pressure fluctuations. The volumetric L-S mass transfer coefficient decreased with increasing gas velocity under the liquid-dominated slug flow regime and became rather less affected under the sparse slug flow regime. By resolving the transition from the liquid-dominated slug flow to the sparse slug flow and capturing the onset of the gas-continuous with pulsing regime, we gained new insights into the hydrodynamic effects of G-L flows on the L-S mass transfer rates in a MPBR.

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“…5,[8][9][10] Flow reactors are now often combined with online analysis to provide data-rich experimental platforms. Online flow analysis methods reported in the literature include GC, [11][12][13][14] HPLC, [15][16][17][18][19][20][21][22][23] MS, 16,[23][24][25][26] UV, 13 IR, [27][28][29][30][31][32] Raman, 33,34 X-ray absorption spectroscopy 28 and NMR 35 as well as viscosity measurements. 36 Additionally, many flow reactors are now being programmed to perform experiments automatically, while collecting experimental data without user supervision.…”

Section: Introductionmentioning

confidence: 99%

An autonomous microreactor platform for the rapid identification of kinetic models

et al. 2019

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A micropacked-bed multi-reactor system with in situ raman analysis for catalyst evaluation

Cited by 15 publications

References 36 publications

Optimization of sol-immobilized bimetallic Au–Pd/TiO ₂ catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

Optimization of sol-immobilized bimetallic Au–Pd/TiO ₂ catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

Study of Liquid–Solid Mass Transfer and Hydrodynamics in Micropacked Bed with Gas–Liquid Flow

An autonomous microreactor platform for the rapid identification of kinetic models

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A micropacked-bed multi-reactor system with in situ raman analysis for catalyst evaluation

Cited by 15 publications

References 36 publications

Optimization of sol-immobilized bimetallic Au–Pd/TiO 2 catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

Optimization of sol-immobilized bimetallic Au–Pd/TiO 2 catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

Study of Liquid–Solid Mass Transfer and Hydrodynamics in Micropacked Bed with Gas–Liquid Flow

An autonomous microreactor platform for the rapid identification of kinetic models

Contact Info

Product

Resources

About

Optimization of sol-immobilized bimetallic Au–Pd/TiO ₂ catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation

Optimization of sol-immobilized bimetallic Au–Pd/TiO ₂ catalysts: reduction of 4-nitrophenol to 4-aminophenol for wastewater remediation