Entrance region(Lévêquelike) mass transfer coefficients in packed bed reactors

High-fidelity CFD modeling of particle-to-fluid heat transfer in packed bed reactors

The novel high-fidelity CFD model for packed bed reactors is validated in terms of Nu regarding particle-to-fluid heat transfer. The model is developed to take into consideration the flow of heat, mass and momentum through and around the particles each shaped without geometrical simplification. In the present approach, cylindrical shaped solid geometries are used to bridge particles in or near ...

Electron-transfer-initiated benzoin- and Stetter-like reactions in packed-bed reactors for process intensification

A convenient heterogeneous continuous-flow procedure for the polarity reversal of aromatic α-diketones is presented. Propaedeutic batch experiments have been initially performed to select the optimal supported base capable to initiate the two electron-transfer process from the carbamoyl anion of the N,N-dimethylformamide (DMF) solvent to the α-diketone and generate the corresponding enediolate ...

Investigation of mass transfer coefficients in irregular packed liquid-liquid extraction columns in the presence of various nanoparticles

In the present study, the effect of various nanofluids on mass transfer coefficients in an irregular packed liquid-liquid extraction column was investigated. The chemical system of toluene–acetic acid–water was used. 10 nm SiO2, TiO2 and ZrO2 nanoparticles with various concentrations were dispersed in toluene-acid acetic to provide nanofluids. The influence of concentration and hydrophobicity/h...

Solution of Noncatalytic Packed Bed Reactors Equations by Finite Element Method

A small-scale regularly packed circulating fluidized bed Part II: Mass transfer

The underlying objective of the present study is to increase gas-solids contact in a circulating fluidized bed by the introduction of obstacles in the riser portion. The presence of such obstacles leads to suppression of radial inhomogeneities in the solids mass flux and concentration, and break-up of solids clusters. At ambient conditions, gas-solids mass transfer was investigated for cocurren...