Intensified LOHC-Dehydrogenation Using Multi-Stage Microstructures and Pd-Based Membranes

Liquid organic hydrogen carriers (LOHC) are able to store hydrogen stably and safely in liquid form. The carrier can be loaded or unloaded with hydrogen via catalytic reactions. However, the release reaction brings certain challenges. In addition to an enormous heat requirement, the released hydrogen is contaminated by traces of evaporated LOHC and by-products. Micro process engineering offers a promising approach to meet these challenges. In this paper, a micro-structured multi-stage reactor concept with an intermediate separation of hydrogen is presented for the application of perhydro-dibenzyltoluene dehydrogenation. Each reactor stage consists of a micro-structured radial flow reactor designed for multi-phase flow of LOHC and released hydrogen. The hydrogen is separated from the reactors’ gas phase effluent via PdAg-membranes, which are integrated into a micro-structured environment. Separate experiments were carried out to describe the kinetics of the reaction and the separation ability of the membrane. A model was developed, which was fed with these data to demonstrate the influence of intermediate separation on the efficiency of LOHC dehydrogenation.

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Condensation By-Products in Wet Peroxide Oxidation: Fouling or Catalytic Promotion? Part I. Evidences of an Autocatalytic Process

Catalysts ◽

10.3390/catal9060516 ◽

2019 ◽

Vol 9 (6) ◽

pp. 516 ◽

Cited By ~ 3

Author(s):

Asunción Quintanilla ◽

Jose L. Diaz de Tuesta ◽

Cristina Figueruelo ◽

Macarena Munoz ◽

Jose A. Casas

Keyword(s):

Flow Reactor ◽

Operating Conditions ◽

Phenol Concentration ◽

Peroxide Oxidation ◽

Wet Peroxide Oxidation ◽

Oxidation Performance ◽

Negative Effect ◽

Initial Phenol Concentration ◽

Kinetics Of ◽

By Products

The present work is aimed at the understanding of the condensation by-products role in wet peroxide oxidation processes. This study has been carried out in absence of catalyst to isolate the (positive or negative) effect of the condensation by-products on the kinetics of the process, and in presence of oxygen, to enhance the oxidation performance. This process was denoted as oxygen-assisted wet peroxide oxidation (WPO-O2) and was applied to the treatment of phenol. First, the influence of the reaction operating conditions (i.e., temperature, pH0, initial phenol concentration, H2O2 dose and O2 pressure) was evaluated. The initial phenol concentration and, overall, the H2O2 dose, were identified as the most critical variables for the formation of condensation by-products and thus, for the oxidation performance. Afterwards, a flow reactor packed with inert quartz beads was used to facilitate the deposition of such species and thus, to evaluate their impact on the kinetics of the process. It was found that as the quartz beads were covered by condensation by-products along reaction, the disappearance rates of phenol, total organic carbon (TOC) and H2O2 were increased. Consequently, an autocatalytic kinetic model, accounting for the catalytic role of the condensation by products, provides a well description of wet peroxide oxidation performance.

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Experimental Study on the Characteristics of Modified Ca-Based Sorbents and its Mercury Adsorption Capability in the Flue Gas

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.424-425.971 ◽

2012 ◽

Vol 424-425 ◽

pp. 971-976

Author(s):

Peng Wang ◽

Jiang Wu ◽

Ping He ◽

Jie He Chen ◽

Qian Yan Liu ◽

...

Keyword(s):

Experimental Study ◽

Electric Power ◽

Flue Gas ◽

Flow Reactor ◽

Phase Flow ◽

Mercury Adsorption ◽

Multi Phase Flow ◽

Removal Efficiencies ◽

Multi Phase ◽

Adsorption Capability

In this paper, Ca-based sorbent, Ca(OH)2 and CaCO3, was modified with different concentration of KMnO4 and their mercury adsorption capability in the flue gas was experimentally conducted by using a lab-scale multi-phase flow reactor system developed by Shanghai University of Electric Power, and the result showed that the removal efficiency of flue gas mercury of Ca-based sorbent was greatly improved with modification by different concentration of KMnO4, and the removal efficiencies were 80.92%，85.38%，82.35%，83.51% and 89.84% respectively. The removal efficiencies of Ca(OH)2 modified with KMnO4 is increased significantly may be because strong oxidation of KMnO4 made Hg0 convert into oxidized mercury, Hg2 +, which is easier to be removed, as well as, the modification by KMnO4 may change the surface properties of Ca(OH)2 so that it became more active to capture mercury in the flue gas.

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Multi-phase flow assessment for the fermentation process in mono-substrate reactor with skeleton bed

Journal of Water and Land Development ◽

10.2478/jwld-2019-0056 ◽

2019 ◽

Vol 42 (1) ◽

pp. 150-156

Author(s):

Grzegorz Wałowski

Keyword(s):

Reynolds Number ◽

Fermentation Process ◽

Flow Reactor ◽

Anaerobic Fermentation ◽

Biogas Production ◽

Production Cycle ◽

Phase Flow ◽

Pig Slurry ◽

Multi Phase Flow ◽

Multi Phase

Abstract The selected techniques were reviewed and their technological aspects were characterized in the context of multi-phase flow for biogas production. The conditions of anaerobic fermentation for pig slurry in a mono-substrate reactor with skeleton bed were analysed. The required technical and technological criteria for producing raw biogas were indicated. Design and construction of the mono-substrate model, biogas flow reactor, developed for cooperation with livestock buildings of various sizes and power from 2.5 kW to 40 kW. The installation has the form of a sealed fermentation tank filled with a skeletal deposit constituting a peculiar spatial system with regular shapes and a rough surface. Incorporating a plant in such a production cycle that enables the entire slurry stream to be directed from the cowshed or pig house underrun channels to the reactor operating in the flow mode, where anaerobic digestion will take place, allows to obtain a biogas. The paper presents preliminary results of experimental investigations in the field of hydrodynamic substrate mixing system for biogas flow assessment by the adhesive bed in the context of biogas production. The aim of the study was to assessment and shows the influence of the Reynolds number on the biogas resistance factor for the fermentation process in mono-substrate reactor with adhesive deposit. The measurement results indicate a clear effect of the Reynolds number in relation to the descending flow resistance coefficient for the adhesive bed.

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Dynamic optimization of a multi-stage spherical, radial flow reactor for the naphtha reforming process in the presence of catalyst deactivation using differential evolution (DE) method

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2010.04.177 ◽

2010 ◽

Vol 35 (14) ◽

pp. 7498-7511 ◽

Cited By ~ 31

Author(s):

Mohammad Reza Rahimpour ◽

Davood Iranshahi ◽

Ali Mohammad Bahmanpour

Keyword(s):

Differential Evolution ◽

Dynamic Optimization ◽

Radial Flow ◽

Catalyst Deactivation ◽

Flow Reactor ◽

Naphtha Reforming ◽

Radial Flow Reactor ◽

Multi Stage

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Oscillatory three-phase flow reactor for studies of bi-phasic catalytic reactions

Chemical Communications ◽

10.1039/c5cc02051d ◽

2015 ◽

Vol 51 (43) ◽

pp. 8916-8919 ◽

Cited By ~ 28

Author(s):

Milad Abolhasani ◽

Nicholas C. Bruno ◽

Klavs F. Jensen

Keyword(s):

Mass Transfer ◽

Oscillatory Flow ◽

Flow Reactor ◽

Catalytic Reactions ◽

Phase Flow ◽

Three Phase ◽

Three Phase Flow ◽

Multi Phase Flow ◽

Multi Phase ◽

Time Limitations

Oscillatory flow reactor strategy removes the mixing, mass transfer and residence time limitations associated with continuous multi-phase flow approaches for studies of bi-phasic C–C and C–N catalytic reactions.

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Kinetics of the catalytic hydrodesulphurization reaction system; hydrogenolysis of thiophene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19802728 ◽

1980 ◽

Vol 45 (10) ◽

pp. 2728-2741 ◽

Cited By ~ 7

Author(s):

Pavel Fott ◽

Petr Schneider

Keyword(s):

Atmospheric Pressure ◽

Active Sites ◽

Flow Reactor ◽

Kinetic Equations ◽

Reaction System ◽

Reaction Products ◽

Molybdenum Catalyst ◽

Cobalt Molybdenum Catalyst ◽

Kinetics Of ◽

Reaction Schemes

Kinetics have been studied of the reaction system taking place during the reaction of thiophene on the cobalt-molybdenum catalyst in a gradientless circulation flow reactor at 360 °C and atmospheric pressure. Butane has been found present in a small amount in the reaction products even at very low conversion. In view of this, consecutive and parallel-consecutive (triangular) reaction schemes have been proposed. In the former scheme the appearance of butane is accounted for by rate of desorption of butene being comparable with the rate of its hydrogenation. According to the latter scheme part of the butane originates from thiophene via a different route than through hydrogenation of butene. Analysis of the kinetic data has revealed that the reaction of thiophene should be considered to take place on other active sites than that of butene. Kinetic equations derived on this assumption for the consecutive and the triangular reaction schemes correlate experimental data with acceptable accuracy.

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Sampling Theory

10.1093/oso/9780198815792.001.0001 ◽

2019 ◽

Cited By ~ 2

Author(s):

David Hankin ◽

Michael S. Mohr ◽

Kenneth B. Newman

Keyword(s):

Natural Resource ◽

Adaptive Sampling ◽

Sampling Theory ◽

Special Importance ◽

Unequal Probability ◽

Multi Stage ◽

R Programming ◽

Multi Phase ◽

Systematic Cluster ◽

Parameter Values

We present a rigorous but understandable introduction to the field of sampling theory for ecologists and natural resource scientists. Sampling theory concerns itself with development of procedures for random selection of a subset of units, a sample, from a larger finite population, and with how to best use sample data to make scientifically and statistically sound inferences about the population as a whole. The inferences fall into two broad categories: (a) estimation of simple descriptive population parameters, such as means, totals, or proportions, for variables of interest, and (b) estimation of uncertainty associated with estimated parameter values. Although the targets of estimation are few and simple, estimates of means, totals, or proportions see important and often controversial uses in management of natural resources and in fundamental ecological research, but few ecologists or natural resource scientists have formal training in sampling theory. We emphasize the classical design-based approach to sampling in which variable values associated with units are regarded as fixed and uncertainty of estimation arises via various randomization strategies that may be used to select samples. In addition to covering standard topics such as simple random, systematic, cluster, unequal probability (stressing the generality of Horvitz–Thompson estimation), multi-stage, and multi-phase sampling, we also consider adaptive sampling, spatially balanced sampling, and sampling through time, three areas of special importance for ecologists and natural resource scientists. The text is directed to undergraduate seniors, graduate students, and practicing professionals. Problems emphasize application of the theory and R programming in ecological and natural resource settings.

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