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Lithium (Li) is a scarce and technologically important element; the demand for which has recently increased due to its extensive consumption, particularly in manufacturing of Li-ion batteries, renewable energy, and electronics. Li is extracted from brines, pegmatite, and clay minerals; though extraction from brines is economically preferred. More than 200 salt plugs are in the Zagros Mountains which represent potential sources for Li exploration. This preliminary study collected first data on the abundance of Li in the salt plugs in southern Iran, and investigated Li distribution during evaporation of halite-producing brine ponds. The XRD analysis of powdered samples showed that gypsum and halite are the dominant solid phases in the ponds in which Li is concentrated in gypsum, while halite is depleted of Li. ICP-MS and ICP-OES analyses showed that Li in brines is concentrated during the evaporation by factors up to 28 with total contents up to 40 mg kg‒1. The Mg/Li ratio was higher than 70, which makes the brine unsuitable for conventional evaporation extraction techniques which require Mg/Li ratios of less than 6. Considering that 25 mg kg‒1 is a suitable concentration of Li for exploration purposes, the results of this study suggest that with the advancement of extraction techniques, the depletion of presently used high-grade Li reserves, the increasing demand for lithium, the need for extraction from diverse sources, and the exploration of new resources, the salt plug brines have an exploratory potential for Li in the future. [ABSTRACT FROM AUTHOR]

Abstract Solvent-free methods for the synthesis of ZSM-5 have been previously reported in the literature. These methods typically involve grinding the starting materials together prior to the hydrothermal reaction step. However, very little is known about the reaction intermediates formed during the mechanochemical pre-reaction or about how the pre-reaction impacts the subsequent hydrothermal synthesis conditions (temperature and length of hydrothermal treatment). In this study, the solvent-free synthesis of ZSM-5 was investigated while varying the length and type of grinding (manual, ball-mill) and the components of the reaction mixture. The initial reactions that occurred between the solid-state raw materials during grinding were monitored by powder X-ray diffraction (pXRD). Extended grinding initiates exchange reactions between several reagents to form NaCl and to liberate ammonia and water. The resulting wet paste undergoes facile thermal conversion to crystalline zeolite ZSM-5 framework structures. These results provide valuable insights used to guide the optimization of the synthesis conditions required to prepare stable, crystalline and high surface area ZSM-5 under solvent-free synthesis conditions. The solvent-free approach contributes to the overall goal of a greener, more sustainable ZSM-5 synthesis. Graphical abstract Image 1 Highlights • Mechanochemical grinding pre-reactions monitored in solvent-free synthesis of ZSM-5. • Grinding initiates exchange reactions between starting materials. • The formation of NaCl and NH 3 were observed during the grinding step. • A paste-like phase of the solid raw materials was formed after 15 min of grinding and leads to highly crystalline ZSM-5. • Insights on mechanochemistry useful for optimizing synthesis conditions. [ABSTRACT FROM AUTHOR]

This study investigates the effect of spatial subsets of Advanced Spaceborne Thermal Emission and Reflection radiometer (ASTER) L1B visible-near infrared and short wave-infrared (VNIR-SWIR) data on matched filtering results at the central part of Kerman magmatic arc, where abundant porphyry copper deposits exist. The matched filtering (MF) procedure was run separately at sites containing hydrothermal minerals such as sericite, kaolinite, chlorite, and jarosite to map the abundances of these minerals on spatial subsets containing 100, 75, 50, and 25 percent of the original scene. Results were evaluated by comparing the matched filtering scores with the mineral abundances obtained by semi-quantitative XRD analysis of corresponding field samples. It was concluded that MF method should be applied to the whole scene prior to any data subsetting. [ABSTRACT FROM AUTHOR]

This study applies Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data and the Mixture Tuned Matched Filtering (MTMF) algorithm to map the sub-pixel distribution of alteration minerals associated with the Masahim volcano, SE Iran for understanding the spatial relationship between alteration minerals and volcano facies. Investigations of the alteration mineralogy were conducted using field-spectroscopy, X-ray diffraction (XRD) analysis and ASTER Short Wave Infrared (SWIR) spectral data. In order to spectrally characterize the stratovolcano deposits, lithological units and alteration minerals, the volcano was divided into three facies: the Central, Proximal, and Medial–distal facies. The reflectance spectra of rock samples show absorption features of a number of minerals including white mica, kaolinite, montmorillonite, illite, goethite, hematite, jarosite, opal, and chlorite. The end-members of key alteration minerals including sericite (phyllic zone), kaolinite (argillic zone) and chlorite (propylitic zone) were extracted from imagery using the Pixel Purity Index (PPI) method and were used to map alteration minerals. Accuracy assessment through field observations was used to verify the fraction maps. The results showed that most prominent altered rocks situated at the central facies of volcano. The alteration minerals were discriminated with the coefficient of determination ( R 2 ) of 0.74, 0.81, and 0.68 for kaolinite, sericite, and chlorite, respectively. The results of this study have the potential to refine the map of alteration zones in the Masahim volcano. [ABSTRACT FROM AUTHOR]

Highlights: [•] Geochemistry of alterations induced by hydrocarbon seepage are investigated. [•] Occurrence of jarosite, natroalunite, and sulfur were measured using XRD analysis. [•] Simultaneous decrease of sulfate and increase of carbonate were detected. [•] Carbon isotope analysis supports a partial contribution of hydrocarbon in carbonates. [•] Increase of Cr, Co, Ni, V, Cd, U, Cu, and Zn are detected in altered areas. [Copyright &y& Elsevier]