Heat and Mass Transfer Properties of Zeolite Coatings: Comparison of Reactive‐ and Spray‐Coated Systems

Abstract

Coated materials are widely used in the process industry. For the generation of adsorption heat exchangers for heat pumps, coated systems offer compactness, robustness as well as high performance. The heat and mass transfer properties into and through functional coating layers play a prominent role in the overall performance of the whole coated systems. In this contribution, laser flash analysis and sorption measurement methods are applied to compare the heat and mass transfer properties of the common spray coating and reactive coating. The experimental results indicate that the reactive coating technique leads to layers with better heat transfer properties and in contrast to lower mass transfer.

Axisymmetric radiative titanium dioxide magnetic nanofluid flow on a stretching cylinder with homogeneous/heterogeneous reactions in Darcy-Forchheimer porous media: Intelligent nanocoating simulation

“…In the benchmarking, the following data is prescribed: The Prandtl number of water is usually 7, and that of metallic nanoparticles much lower liquid metal Prandtl numbers are of the order of 0.01); combining these two materials yields Prandtl numbers greater than unity but much less than pure water i.e. Pr = 2 [73]. The Schmidt number prescribed (Sc = 0.22) corresponds to oxygen and hydrogen diffusing in aqueous polymers as noted by Incropera et al [74] for which the mass diffusion rate of species A (oxygen) and species B (hydrogen) greatly exceeds the viscous diffusion rate (Schmidt number is the ratio of viscous diffusivity and mass (species) diffusivity).…”

Removal of Chromium (VI) and Lead (II) from Aqueous Solution Using Domestic Rice Husk Ash- (RHA-) Based Zeolite Faujasite

“…And silicon is an essential structural element for this material. Zeolite Faujasite-type is widely used as ion-exchange material due to its thermochemical stability, being easily tunable and its selective sorption properties, synthesizability using inexpensive elements, and environmental compatibility [20][21][22]. The inside cages or surface of 7.2 nm sized pore of zeolite FAU acts as sorption active sites for ion species due to the presence of positive aluminum in the framework [22].…”

An Industrial Approach for the Optimization of a New Performing Coated Adsorber for Adsorption Heat Pumps

“…The resulting microfibrous coatings allow good heat transfer, which offers a high exchange surface area and high permeability, with an overall improvement in both heat and mass transfer efficiencies. Chanda et al [19] proposed Y zeolite and SAPO-34-based coatings (about 60 µm thick) deposited on aluminum sheets by spray-coating technique by using 30 wt.% attapulgite clay binder. This solution is interesting as inorganic binders are generally more stable thermally and present less outgassing problems during operation.…”