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Future: Green and Sustainable Nano
Published in Chaudhery Mustansar Hussain, Gustavo Marques da Costa, Environmental, Ethical, and Economical Issues of Nanotechnology, 2022
Gustavo Marques da Costaa, Michele dos Santos Gomes da Rosati
Because these technologies involve extraction from solutions, it may also prove economic to leach materials containing useful elements and recover metals from the leachates. This could be looked on as an extension of present hydrometallurgy, as with the present-day cyanide-based solution extraction of Au, or the leaching of Cu with dilute H2SO4. For a further example, during World War II an experimental process for magnesium production involved the dissolution of olivine ((Mg,Fe)SiO4) by a strong mineral acid, such as HC1. Obviously, Fe could be a by-product (unwanted at the time); these authors also noted that Ni and Co, which commonly substitute for Fe and Mg at concentrations up to 2000 and 130 ppm, respectively, could be recovered. Finally, another unwanted by-product was silica gel formed from the disaggregated mineral, but this may itself prove useful in a silicate-based nanotechnology, as discussed below. Olivine is a ubiquitous mineral; it makes up most of planetary mantles and is locally abundant at the surface of both the Earth and the Moon.
Petroleum Geological Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Olivine silicate is an olive-green or grey-green or brown mineral in igneous rock, containing varying percentages of bivalent metals iron, magnesium and others. Olivine silicates are represented by the general formula (Fe, Mg)SiO4. Their crystal structure is orthorhombic. Olivine is used as a gem stone and is said to be associated with healing properties.
Toxic Responses of the Lung
Published in Stephen K. Hall, Joana Chakraborty, Randall J. Ruch, Chemical Exposure and Toxic Responses, 2020
The olivine group of igneous rocks are iron and magnesium silicates with island structures of SiO42− units. Olivine is used principally in foundries, primarily as a special sand for mold-making in brass, aluminum, and magnesium foundries. It is used as a refractory (bricks) material, in mixes for furnace linings, and as a source of magnesium in fertilizer. No disease or pneumoconiosis from olivine mineral has been observed in humans.
On the glide of [100] dislocation and the origin of ‘pencil glide’ in Mg2SiO4 olivine
Published in Philosophical Magazine, 2019
S. Mahendran, Ph. Carrez, P. Cordier
The pencil glide mechanism has also been reported in olivine (Mg,Fe)2SiO4 [4]. Olivine is a common silicate, main constituent of the upper mantle of the Earth. Its orthorhombic structure (hereafter described using the Pbnm space group) can be described as a slightly distorted hcp sub-lattice of oxygen ions with cations occupying part of octahedral and tetrahedral interstitial sites. Deformation experiments performed on single crystals show the occurrence of [100] and [001] slip in olivine [5,6], corresponding to classical < a > and < c > slip of the hcp lattice. Transmission electron microscopy examinations of either naturally or experimentally deformed samples in various conditions usually report slip of dislocations with [001] Burgers vector in (010), (100) or (110) at low temperature [7–12]. At high temperature, the [100](010) slip system has been documented but also slip systems [100]{0kl} have been reported leading to invoke pencil glide of dislocations with [100] Burgers vectors. Since the early work of Rayleigh [4], pencil glide mechanism in olivine has been continuously invoked notably for the modelling of Crystal Preferred Orientations (CPOs) which may strongly affect seismic waves travel times and give rise to seismic anisotropy [13].
Sorptive equilibrium profile of fluoride onto aluminum olivine [(FexMg1−x)2SiO4] composite (AOC): Physicochemical insights and isotherm modeling by non-linear least squares regression and a novel neural-network-based method
Published in Journal of Environmental Science and Health, Part A, 2018
Partha S. Ghosal, Ashok K. Gupta
Olivine [(FexMg1−x)2SiO4] is the most abundant mineral in the Earth's upper mantle and is rich in mostly magnesium, silica, iron along with some percentage of aluminum.[20] This sandy material is used as a potential support in the field of catalysis.[21] However, the aluminum impregnated olivine has rarely been used either in the field of catalysis or for the water treatment, although the composition of olivine indicates that the material may be promising for environmental engineering. The present study aims to explore the adsorption potential of the AOC for defluoridation.