The Durra (Sorghum) stalk was employed as a novel precursor for the formation of high surface area activated carbons (ACs) by utilizing ZnCl2 as activating agent followed by pyrolysis in a flow of N2 gas. The formation of ACs has been investigated at different pyrolysis temperatures (400, 500 and 600 °C) and different ZnCl2 impregnation concentrations. The results indicated that, ... إقراء المزيد

High surface area SiO2 samples were synthesized by one-step hydrolysis and co-condensation at different pH (between 3.0 and 6.0) using tetraethyl orthosilicate as the Si source and formamide as the drying additive. The effects of the presence of H2O, formamide and NH3 solution on the hydrophobic nature, textural properties and catalytic functionality of SiO2 were investigated. The physico-chemical properties of ... إقراء المزيد

A series of 10, 20 and 30% (w/w) La2O3-Fe2O3/silica composites were synthesized by mixing of La-Fe citrate complex gels with spherical silica sols. This was followed by calcination of the formed xerogel at 550 °C and 750 °C for 3 h. The materials were characterized by XRD, simultaneous thermal analyses (TGA-DTA), FTIR, N2 gas adsorption/desorption isotherms at ⿿196 °C, and ... إقراء المزيد

Thermally stable nanoparticles (NPs) of anatase phase titania, TiO2, were prepared by calcinations of acidic peptization products of titania xerogel, TiO2∙ xH2O, that formed via an eco-friendly method. The method was based on hydrolysis of titanium isopropoxide over a long time period under atmospheric conditions (temperature 25 ± 5 °C and humidity 50 ± 10‰). Acidic peptization accompanied with ultrasonic ... إقراء المزيد

IRON OXIDE/MCM-41 NANOCOMPOSITES, FE(2)O(3)/MCM-41, CONTAINING 5%, 10%, AND 20% (W/W) IRON OXIDE, WERE PREPARED VIA A DIRECT NONHYDROTHERMAL METHOD AT ROOM TEMPERATURE. THE PREPARATIONS WERE PREFORMED BY USING IRON(III) NITRATE, TETRA-ETHOXYSILANE (TEOS), AND CETYLTRIMETHYLAMMONIUM BROMIDE (CTAB) MIXED OR UNMIXED WITH DODECYLTRIMETHYLAMMONIUM BROMIDE (DTAB). THE PRODUCED MATERIALS WERE DRIED AND CALCINED AT 550 °C FOR 3 H. TEST MATERIALS WERE CHARACTERIZED ... إقراء المزيد

SPHERICAL-PARTICLE MCM-41 WAS SYNTHESIZED AT ROOM TEMPERATURE, AND, THEN, IMPREGNATED WITH AQUEOUS SOLUTIONS OF NH4VO3 TO PRODUCE VARIOUSLY LOADED VO_X_/MCM-41 COMPOSITE MATERIALS. BULK AND SURFACE PROPERTIES OF THE MATERIALS THUS PRODUCED WERE CHARACTERIZED BY MEANS OF X-RAY POWDER DIFFRACTOMETRY (XRD), INFRARED SPECTROSCOPY (FTIR), N2 SORPTIOMETRY AND X-RAY PHOTOELECTRON SPECTROSCOPY (XPS). RESULTS OBTAINED INDICATED THAT SUBSEQUENT CALCINATION AT 550 °C (FOR ... إقراء المزيد

IRON OXIDE/SILICA (FE:SI AS 1:10 ATOMIC RATIO) COMPOSITE MATERIALS HAVE BEEN PREPARED BY CALCINATION FOR 3 H AT DIFFERENT TEMPERATURES (400–900 °C) OF XEROGEL PRECURSOR OBTAINED VIA A FORMAMIDE MODIFIED SOL–GEL PROCESS. THE PROCESS INVOLVED TEOS AND IRON(III) NITRATE, NITRIC ACID AND FORMAMIDE. GENESIS OF THE COMPOSITE MATERIALS FROM THE XEROGEL PRECURSOR HAS BEEN INVESTIGATED BY TGA, DSC, FTIR, XRD, ... إقراء المزيد

FORMATION OF MESOPOROUS ALUMINA AT ROOM TEMPERATURE VIA COMBINED UTILIZATION OF ACETIC ACID (AS AN ORGANIC MODIFIER) AND CETYL TRIMETHYL AMMONIUM BROMIDE (CTAB) AS A CATIONIC SURFACTANT HAS BEEN INVESTIGATED IN N-HEPTANE MEDIUM. THE REACTANTS MOLAR RATIO WAS ALUMINUM ISOPROPOXIDE:ACETIC ACID:WATER:CTAB:N-HEPTANE, AS 1:1:3:_X_:15, WHERE _X_ WAS 1 OR 3. THE CALCINED MATERIALS (AT 600 °C FOR 3 H) WERE CHARACTERIZED ... إقراء المزيد

HUMIDITY SENSING PROPERTIES WERE INVESTIGATED FOR A THERMALLY STABLE, HIGH SURFACE AREA AND POROUS COMPOSITE MATERIAL COMPOSED OF IRON OXIDE/SILICA (FE:SI AS 1:10 ATOMIC RATIO). THE INVESTIGATED COMPOSITE MATERIAL WAS FORMED BY CALCINATION FOR 3 H AT 600 °C OF THE XEROGEL PRECURSOR, OBTAINED VIA A FORMAMIDE-MODIFIED SOL–GEL PROCESS. THE PRODUCED COMPOSITE MATERIAL WAS CHARACTERIZED BY A HIGH SURFACE AREA, ... إقراء المزيد

NANOCOMPOSITE MATERIALS CONTAINING 10% AND 20% IRON OXIDE/SILICA, FE2O3/SIO2 (W/W), WERE PREPARED BY DIRECT HYDROLYSIS OF AQUEOUS IRON (III) NITRATE SOLUTION IN SOLS OF FRESHLY PREPARED SPHERICAL SILICA PARTICLES (STÖBER PARTICLES) PRESENT IN THEIR MOTHER LIQUORS. THIS WAS FOLLOWED BY AGING, DRYING, CALCINATION UP TO 600 °C THROUGH TWO DIFFERENT RAMP RATES, AND THEN ISOTHERMAL CALCINATIONS AT 600 °C FOR ... إقراء المزيد