A bench work study was carried out to investigate the use of kaolinitic clay containing 29.4% Al2O3 extremely abundant in Saudi Arabia for the production of pure alumina by calcination at 700 o C for 1h (recommended by previous investigators) then leached by hydrochloric acid. The effects of leaching temperature (25 o C to boiling temperature), period of activation (10-150 minutes), acid concen...

This paper presents the findings of a study on adsorption of dichlorodiphenythreechloroethen (DDT) and polychlorinated biphenyls (PCBs) on three nanomaterials including Multi walled Carbon Nanotube (MWNT), nano-clay and nano-alumina. DDT and PCBs are of significant concern due their high toxicity and long environmental half-lives. Experiments were conducted using batch adsorption procedures at ...

The effect of light scattering on measurement of UV absorbance and penetration of germicidal UVC irradiance in a UV reactor were studied. Using a standard spectrophotometer, absorbance measurements exhibited significant error when particles that scatter light were present but could be corrected by integrating sphere spectroscopy. Particles from water treatment plants and wastewater effluents ex...

Selective fatty acid hydrophobization of the inner surface of tubule halloysite clay is demonstrated. Aqueous phosphonic acid was found to bind to alumina sites at the tube lumen and did not bind the tube's outer siloxane surface. The bonding was characterized with solid-state nuclear magnetic resonance ((29)Si, (13)C, (31)P NMR), Fourier transform infrared (FTIR), and X-ray photoelectron spect...

Abstract Refractory ceramics were produced from clays and alumina waste. Specimens shaped by uniaxial pressing, subjected to thermal analysis dilatometry heat-treated in a conventional furnace at 1300 1400oC, applying heating rate of 5oC/min dwell time 2 3 hours the maximum temperature. The samples characterized X-ray diffraction (XRD), scanning electron microscopy (SEM) physicomechanical prope...

High-alumina minerals refer, in this paper, to Al-rich, normal sedimentary phases, including gibbsite, boehmite, diaspore, possibly "proto-diaspore" and "proto-alunite", "Al-chlorite", and corundum, in association with kaolin minerals. They may be derived from any common Al-containing rock. Processes of origin include direct bauxitization of non-clay silicate minerals and rocks, and the desilic...

DRIFTS, was used to study small organic molecules, with and without functional groups, adsorbed to the surface of γ-alumina and kaolinite clay from a non-polar solvent. Adsorbed water is present on the surface of both minerals and this influences the adsorption of organic molecules from, the non-polar solvent, onto the mineral surface, particularly the interaction of polar functional groups wit...

Abstract Porous mullite ceramics were prepared from mixtures of Egyptian kaolinite-clay and calcined α-alumina powder. The effects two methods compaction as well types binder investigated. influence sintering temperature on the physical properties, crystalline phase, compressive strength microstructure was studied. Mullite bodies processed by uniaxial pressing utilizing 15wt. % water at 1500°C ...

Two processes for extracting alumina from low-grade ores are described, one applicable to both clays and high-silica bauxites, and the other only to bauxites. In the former process, a line-containing sinter is prepared and annealed by cooling it slowly through the range of 1,3000 to 1,2000 C. The annealed sinter dusts to a powder which requires no grinding. This material is extracted with a sol...