Phytoliths are formed from silica carried up groundwater and some plants. The weathering of silicate minerals at the Earth’s surface provides large amounts soluble silica, which is absorbed by growing In solution, exists as mono silicic acid Si (OH4) with pH values 2–9. It upward in vascular system becomes concentrated during transpiration around leaf stomata. supersaturated solution begins to ...

Using industrial spent Bayer-liquor solution and 95 °C temperature, the dissolution desilication products formation kinetics of five raw kaolinite samples obtained from different sources were found to display profound differences. It was hypothesized that these differences connected physico-chemical properties solids. The solids characterized by powder X-ray diffractometry, N2 adsorption-desorp...

Natural clinoptilolite zeolite (CLP) in its original or metal ion- exchanged form (Ni2+) is a weak adsorbent for relatively large thiophene derivative molecules like benzothiophene (BT) and di-benzothiophene (DBT), due to its rather restricted micro-channel structure. A novelty of this work is that upon desilication treatments, it is possible to enhance the adsorption behavior of Ni2+-exchanged...

Low grade diasporic bauxite in the Jajarm mine with an A/S (Al2O3/SiO2) ratio of 2.3 is not usable in the Bayer process at Jajarm Alumina Complex. Due to the severe interlocking effect between the diaspore and aluminosilicate minerals (Chamosite and Kaolinite) and iron-containing minerals in a microcrystal matrix, the thermo-chemical treatment, which is independent from micro-mineralogy, was ch...

Reductive leaching in the Bayer cycle using iron (2+) allows for Al extraction to be significantly increased through magnetization of Al-goethite and Al-hematite. However, use expensive salts or powder as a source leads significant increase production costs. In this work, feasibility new method, reductive bauxite an electrolysis process, was investigated. The reduction minerals boehmitic both s...

The present article investigates the potential of co-calcination with kaolinite as a sector-wide solution for transformation bauxite residue into an effective supplementary cementitious material (SCM). Bauxite residues from eight alumina refineries were co-calcined 30 wt% at 750°C. SCMs moderately high reactivities obtained. Mortars replacement Portland cement (CEM I) by had relative strengths ...