Nanopore silicalite type membranes were prepared on the outer surface of a porous-mullite tube by in situ liquid phase hydrothermal synthesis. The hydrothermal crystallization was carried out under an autogenously pressure, at a static condition and temperature of 180 °C with tetrapropylammonium bromide (TPABr) as a template agent. The molar composition of the starting gel of silicalite zeolite...

We report the quantitative, non-destructive determination of the concentration profile of an organic molecule in a nanoporous polycrystalline zeolite molecular sieve membrane, by step scan infra-red photoacoustic experiments and analysis. An important application of stepscan photoacoustic spectroscopy is the transport-model-independent experimental description of membrane transport, by simultan...

A simplified mathematical model is proposed to provide an analytic solution for the transient behavior of a Langmuirian zeolite membrane subjected to a step increase in sorbate pressure at the upstream surface at time zero. The concentration profiles derived from the simplified model agree with those calculated by numerical solution of the governing partial differential equation. The model is u...

The Kongsberg and Bamble lithotectonic domains of SE-Norway are known as classical Precambrian high-grade metamorphic terrains. area has undergone extensive metasomatism with formation albitites scapolite-rich rocks numbers previously economically important deposits including the Silver Modum Cobalt mines. We demonstrate here that central part domain (Kragerø area) locally developed low-grade m...

The paper is concerned with (i) the hydrothermal synthesis of hydrous zirconium dioxide (HZD) bearing analcime (HZD-ANA, zirconia-analcime) and (ii) its sorption properties respect to Cs+ Sr2+. HZD-ANA particles were synthesized from coal fly ash cenospheres composed aluminosilicate glass (SiO2/Al2O3)wt.=3.1 characterized by PXRD, SEM-EDS, STA, low-temperature N2 adsorption. non-radioactive sim...

A zeolite NaA (A-type zeolite of ca. 0.4 nm pore size; Linde Type A, LTA) membrane for the dehydration of alcohol was characterized by X-ray diffraction analysis (XRD). Also, the relationship between the X-ray absorption and the EtOH/H2O pervaporation (PV) dehydration performance (water selectivity and permeation flux) of the LTA membrane was first investigated. The LTA membranes used here were...

Zeolite membranes are highly attractive in energy efficient, selective separation technologies. Their high selectivity originates from adsorption, diffusion and even molecular sieving. High flux zeolite (> 1 mol s−1m−2) with a sub-micrometer thickness mechanically stabilized by porous, often multilayer, support. Transport mechanisms layer support, however, counteracting regarding selectivity, s...

vanadium silicates such as v-al-analcime, v-analcime, v-magediite and v-zsm-11 were synthesized using vanadium pentoxide or vanadyl sulfates. vanadium silicates with analcime structure with and without aluminum (v-al-analcime, v-analcime) were prepared as pure phase by hydrothermal crystallization from a gel with molar composition of (1 sio2; 0.2 v2o5; 1 na2o; 0.034 al2o3; 35.7 h2o) and (1 sio2...

Molecular sieving MFI-type zeolite membranes were prepared by a secondary growth method without using an organic template. Silicalite membranes with intercrystalline pores minimized or eliminated were obtained by this synthesis method which avoids the template removal step. The silicalite membrane exhibits molecular sieving characteristics with pervaporation separation factor for p-xylene to o-...