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Petroleum Geochemical Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Mineralization is broad term; it is used in geology, metallurgy and soil science. The mineralization process is the deposition or formation or introduction of a particular mineral or ore or nutrient or fossilization of organic matter into sedimentary rock or soil. It should not be confused with sedimentation. Sedimentation is a complex geological process involving the weathering, erosion, deposition, transportation and settling of mineral. The sedimentation process begins with tiny mineral particles and leads to the formation of a solid formidable framework of sedimentary rock. Sedimentation is slow process; it can only be expressed in geological time scale. Mineralization is related to the following points: The formation of minerals and ore in soil and subsurface conditions.The subsequent deposition of minerals and ores.The process of the fossilization of organic matter in the inorganic matrix.The conversion and oxidation of complex organic matter to simple inorganic compounds and soil micronutrients.
Hydrothermal Mineralization
Published in Sandeep Kumar, Florin Barla, Sub- and Supercritical Hydrothermal Technology, 2019
The term “hydrothermal mineralization” refers to heterogeneous reactions (crystallization) carried out in an aqueous solvent, sometimes with the presence of a mineralizer, under high temperature and pressure conditions (above 100°C and 1 bar) [5–8]. The process can be carried out either under sub- or supercritical water conditions, however the tendency is, when possible, to keep milder operating conditions. Under hydrothermal conditions, the physical properties of the solvent (i.e., water) change, so that high solvation power, high compressibility and mass transport allow the occurrence of various different reactions, e.g., synthesis/stabilization of new phases, production of crystals with desired shape and size (including nanocrystals), and growth of several inorganic compounds that are characterized by low solubility at ambient conditions. For example, it is the only method that can be employed for the precipitation of large crystals of α-quartz, or of compounds with elements in oxidation states otherwise difficult to obtain (e.g., transitional metal compounds such as chromium (VI) oxide) [2]. Moreover, HTM offers several advantages compared to conventional crystallization carried out under ambient or near-ambient conditions in terms of purity, homogeneity, reproducibility, and symmetry of the obtained crystals.
Ground-Water Treatment for Chlorinated Solvents
Published in John E. Matthews, Handbook of Bioremediation, 2017
Perry L. McCarty, Lewis Semprini
Figure 5.11 illustrates contamination of soil and ground water by leakage from a storage tank, a common way by which contamination with liquids occurs (McCarty, 1990). As the liquid is pulled downward by gravity, residuals left behind contaminate the surface soil, the unsaturated (vadose) zone, and finally the aquifer containing the ground water itself. After the leakage is found and stopped, and the most highly contaminated soil around the tank is excavated, one must then deal with a lower-concentration residual in the soil, the vadose zone, and the ground water. If the contaminating liquid is a mixture of many different compounds, then each may move and be transformed at different rates. Biological and chemical transformations may not lead to mineralization, but may result in producing other organic chemicals that may be either less or more harmful than the original. Organice may become strongly sorbed onto subsurface minerals or may penetrate into cracks so that they are not accessible by microorganisms or their enzymes.
Photocatalytic oxidation of pollutants in gas-phase via Ag3PO4-based semiconductor photocatalysts: Recent progress, new trends, and future perspectives
Published in Critical Reviews in Environmental Science and Technology, 2022
Y. Naciri, A. Hsini, A. Bouziani, R. Djellabi, Z. Ajmal, M. Laabd, J. A. Navío, A. Mills, C. L. Bianchi, H. Li, B. Bakiz, A. Albourine
The type and the concentration of the gas pollutant significantly affect the photocatalytic oxidation efficiency. Indeed, the photooxidation efficiency depends on the photocatalyst's affinity toward the type of pollutant, wherein species showing good adsorption on the photocatalyst have more possibility to be oxidized (Jafarikojour et al., 2015; Mamaghani et al., 2017; Zhong et al., 2013). More by-products are likely to be produced at higher pollutant concentrations, and in some cases this will impede the overall mineralization process. Therefore, photocatalysis for air purification is usually more effective when carried out using low concentrations of contaminants although this will also depend upon the photocatalyst's surface chemistry and porosity.
“Reasonable prospects” in mineral resource estimation and reporting
Published in CIM Journal, 2023
R. Pressacco, L. Evans, J. Postle
The RPEEE requirement is a fundamental component of a mineral resource in many mining jurisdictions. The potential technical and economic viability of the mineralization must be demonstrated using reasonable assumptions. As guidance, CIM (2019) provides the following: For a Mineral Resource, factors significant to technical feasibility and economic viability should be current, reasonably developed, and based on generally accepted industry practice and experience. The assumptions should have a reasonable basis, be clearly defined, and should reflect the level of information, knowledge and stage of development of the mineral property at the time.