Development of a conductometric biosensor for the urea detection has been reported. It was created using a non-typical method of the recombinant urease immobilization via adsorption on nanoporous particles of silicalite. It should be noted that this biosensor has a number of advantages, such as simple and fast performance, the absence of toxic compounds during biosensor preparation, and high re...

1. Introduction 1. Introduction Information on mass transport in polycrystalline zeolite membranes is necessary for a theoretical estimation of the membrane performances. Zeolite membranes are usually prepared as thin layer of an assembly of small zeolite crystals including many intercrystalline regions. Thus, the intercrystal region would influence their individual diffusion properties, which ...

A possibility of the creation of potentiometric biosensor by adsorption of enzyme urease on zeolite was investigated. Several variants of zeolites (nano beta, calcinated nano beta, silicalite, and nano L) were chosen for experiments. The surface of pH-sensitive field-effect transistors was modified with particles of zeolites, and then the enzyme was adsorbed. As a control, we used the method of...

Zeolites of MFI-type belong to the most important zeolite structures in catalysis and are used in many shape-selective processes in petroleum refining industry, in particular for the kinetic separation of alkane isomers. Practically all important applications involve mixtures. However, due to the experimental difficulty, the number of experimental studies of mixture adsorption and diffusion is ...

We demonstrate, for the first time, in the Baeyer-Villiger oxidation of cyclohexanone with aqueous hydrogen peroxide under conditions aimed at obtaining ε-caprolactone, that a thermally activated radical reaction leads to the concurrent formation of adipic acid, even when a stoichiometric amount of the oxidant is used. In fact, ε-caprolactone is the primary reaction product, but it is more reac...

1. Introduction Zeolites are microporous materials which are ideally suited for different industrial applications, e.g. as separators or catalysts. Their applicability is determined by the dynamical and the adsorptive properties of the molecules inside their micropores. Adsorption kinetics in zeolite has been explained as a two-step process, adsorption on the external crystal surface and subseq...