scholarly journals Mineralogy, Geochemistry and Genesis of Zeolites in Cenozoic Pyroclastic Flows from the Asuni Area (Central Sardinia, Italy)

Minerals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 268
Author(s):  
Angela Mormone ◽  
Monica Piochi
Keyword(s):  
Natural Zeolite ◽  
Pyroclastic Flows ◽  
Bulk Rock ◽  
Pyroclastic Deposits ◽  
Geochemical Characterization ◽  
X Ray ◽  
Genetic Process ◽  
Dioctahedral Smectite ◽  
Hydrothermal Environment

Natural zeolite occurrences have been recognized in several Cenozoic pyroclastic deposits in central Sardinia. This study concerns the mineralogical and geochemical characterization of the zeolitized tuffites in the Asuni area (Oristano province) and aims to complement information regarding the zeolitization processes developed in the nearby Allai deposits. Optical and scanning electron microscopy, X-ray powder diffraction, qualitative vs. quantitative microanalyses and bulk-rock geochemistry were performed. Analytical results allow defining the mineral distribution, textural relationships and geochemical features of the zeolite-bearing rocks. The most abundant secondary minerals are Ca-Na mordenites. Contrarily to the most common worldwide clinoptilolite + mordenite paragenesis, mordenite is dominant and occurs in different morphologies, rarely coexisting with clinoptilolite in the studied volcanic tuffites. Glauconite and dioctahedral smectite complete the authigenic assemblages. The primary volcanic components mostly include plagioclase, quartz and glass shards, roughly retaining their original appearance. The tuffites range in composition from dacite to rhyolite. The collected dataset shows that zeolitization is most abundant in coarser-grained deposits and points to a genetic process that mainly involves an open hydrothermal environment governed by aqueous fluids with significant marine component, in post eruption conditions.

HIGH ENERGY SYNCHROTRON X-RAY MICROSPECTROSCOPY FOR GEOCHEMICAL CHARACTERIZATION OF TERRESTRIAL AND EXTRATERRESTRIAL SAMPLES

2016 ◽  
Author(s):  
Antonio Lanzirotti ◽  
◽  
Stephen R. Sutton ◽  
Matt Newville ◽  
Jeffrey P. Fitts ◽  
...  
Keyword(s):  
High Energy ◽  
Geochemical Characterization ◽  
X Ray

scholarly journals Preparation and Characterization of the Sulfur-Impregnated Natural Zeolite Clinoptilolite for Hg(II) Removal from Aqueous Solutions

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 217
Author(s):  
Marin Ugrina ◽  
Martin Gaberšek ◽  
Aleksandra Daković ◽  
Ivona Nuić
Keyword(s):  
Chemical Modification ◽  
Aqueous Solutions ◽  
Specific Surface ◽  
Surface Area ◽  
Natural Zeolite ◽  
Contact Time ◽  
Liquid Ratio ◽  
X Ray ◽  
Solid Liquid

Sulfur-impregnated zeolite has been obtained from the natural zeolite clinoptilolite by chemical modification with Na2S at 150 °C. The purpose of zeolite impregnation was to enhance the sorption of Hg(II) from aqueous solutions. Chemical analysis, acid and basic properties determined by Bohem’s method, chemical behavior at different pHo values, zeta potential, cation-exchange capacity (CEC), specific surface area, X-ray powder diffraction (XRPD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), as well as thermogravimetry with derivative thermogravimetry (TG-DTG) were used for detailed comparative mineralogical and physico-chemical characterization of natural and sulfur-impregnated zeolites. Results revealed that the surface of the natural zeolite was successfully impregnated with sulfur species in the form of FeS and CaS. Chemical modification caused an increase in basicity and the net negative surface charge due to an increase in oxygen-containing functional groups as well as a decrease in specific surface area and crystallinity due to the formation of sulfur-containing clusters at the zeolite surface. The sorption of Hg(II) species onto the sulfur-impregnated zeolite was affected by the pH, solid/liquid ratio, initial Hg(II) concentration, and contact time. The optimal sorption conditions were determined as pH 2, a solid/liquid ratio of 10 g/L, and a contact time of 800 min. The maximum obtained sorption capacity of the sulfur-impregnated zeolite toward Hg(II) was 1.02 mmol/g. The sorption mechanism of Hg(II) onto the sulfur-impregnated zeolite involves electrostatic attraction, ion exchange, and surface complexation, accompanied by co-precipitation of Hg(II) in the form of HgS. It was found that sulfur-impregnation enhanced the sorption of Hg(II) by 3.6 times compared to the natural zeolite. The leaching test indicated the retention of Hg(II) in the zeolite structure over a wide pH range, making this sulfur-impregnated sorbent a promising material for the remediation of a mercury-polluted environment.

Mineralogical and geochemical characterization of archaeological ceramics from the 16th century El Badi Palace, Morocco

Clay Minerals ◽  
2018 ◽  
Vol 53 (3) ◽  
pp. 459-470
Author(s):  
Mouhssin El Halim ◽  
Lahcen Daoudi ◽  
Meriam El Ouahabi ◽  
Valérie Rousseau ◽  
Catherine Cools ◽  
...  
Keyword(s):  
Sixteenth Century ◽  
Chemical Characterization ◽  
Raw Material ◽  
Maximum Temperature ◽  
X Ray Diffraction ◽  
Archaeological Ceramics ◽  
Geochemical Characterization ◽  
X Ray ◽  
Firing Tests

ABSTRACTTextural, mineralogical and chemical characterization of archaeological ceramics (zellige) from El Badi Palace (Marrakech, Morocco), the main Islamic monument from the Saadian period (sixteenth century), has been performed to enhance restoration and to determine the technology of manufacturing. A multi-analytical approach based on optical and scanning electron microscopy, cathodoluminescence, X-ray fluorescence and X-ray diffraction was used. Re-firing tests on ceramic supports were also performed to determine the firing temperatures used by the Saadian artisans. A calcareous clay raw material was used to manufacture these decorative ceramics. The sherds were fired at a maximum temperature of 800°C in oxidizing atmosphere. The low firing temperature for ‘zellige’ facilitates cutting of the pieces, but also causes fragility in these materials due to the absence of vitreous phases.

scholarly journals Penggunaan ZnO/zeolit sebagai katalis dalam degradasi tartrazin secara ozonolisis

2021 ◽  
Vol 12 (1) ◽  
pp. 53-64
Author(s):  
Zilfa Zilfa ◽  
Safni Safni ◽  
Febi Rahmi
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Electron Microscope ◽  
Natural Zeolite ◽  
Zeolite Catalyst ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zeolite Structure ◽  
Scanning Electron

An investigation on modification of natural zeolite with ZnO for the degradation of tartrazine. In this study, ZnO as a semiconductor is modified into a natural zeolite as support to form ZnO/zeolite that can increase the efficiency degradation of tartrazine. Further, the formed catalyst was added to tartrazine by determining the variation in ozonolysis time, the amount of addition of the catalyst, and the addition of a catalyst time. The results of degradation were determined by UV-Vis spectrophotometer at 424 nm. The result showed that the percentage of degradation obtained on each catalyst in the degradation. The resulted percent degradation of 20 ml of tartrazine at concentration of 15 mg/L using 20 mg ZnO/zeolite was 56.80%, while using 0.77 mg ZnO was 42.25%, and with the addition of 19.23 mg of Zeolite was 31.18%, all of that condition was proceeded by 40 minutes of ozonolysis. Thus, the result indicates that the ZnO/zeolite catalyst can increase percentages of tartrazine degradation by ozonolysis. It is known that the catalyst ZnO/zeolite is very effective in increasing the degradation of tartrazine. Analysis of tartrazine compounds using fourier-transform infrared spectroscopy (FTIR) after degradation changes in wavenumber indicates that there is a breaking of the bonds of tartrazine compounds. Characterization of ZnO/zeolite catalyst using FTIR, X-Ray diffraction (XRD) and scanning electron microscope (SEM), in each spectrum there was no shift, indicating that there is no change in ZnO/zeolite structure

scholarly journals Mineralogical and Geochemical Characterization of Asbestiform Todorokite, Birnessite, and Ranciéite, and Their host Mn-Rich Deposits from Serra D’Aiello (Southern Italy)

Fibers ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 9
Author(s):  
Andrea Bloise ◽  
Domenico Miriello ◽  
Rosanna De Rosa ◽  
Giovanni Vespasiano ◽  
Ilaria Fuoco ◽  
...  
Keyword(s):  
Energy Dispersive Spectrometry ◽  
Southern Italy ◽  
Industrial Applications ◽  
Scanning Calorimetry ◽  
Geochemical Characterization ◽  
X Ray ◽  
Transmission Electron ◽  
Terrestrial Environments ◽  
Strong Control

Manganese ores, especially the oxyhydroxides in their different forms, are the dominant Mn-bearing minerals that occur in marine and terrestrial environments, where they are typically found as poorly crystalline and intermixed phases. Mn oxyhydroxides have a huge range of industrial applications and are able to exert a strong control on the mobility of trace metals. This paper reports the results of a detailed study on the Mn oxyhydroxides occurring in the manganiferous deposit outcropping in the Messinian sediments from Serra D’Aiello (Southern Italy). Nine Mn samples were characterized in detail using X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), thermogravimetry (TG), transmission electron microscopy combined with energy dispersive spectrometry (TEM/EDS), and X-ray fluorescence (XRF). The results indicated that the Mn deposit included the oxyhydroxide mineral species birnessite, todorokite, and rancièite. The size, morphology, and chemical composition of Mn oxyhydroxide samples were investigated in order to define their impact on the environment and human health. Todorokite displayed asbestiform shapes and could disperse fibers of breathable size in the air. Furthermore, since in-depth characterization of minerals within Mn deposits may be the first step toward understanding the genetic processes of manganese deposits, hypotheses about the genesis of the Mn oxyhydroxide deposits were discussed.

scholarly journals Mineralogical and Geochemical Characterization of Gold Bearing Quartz Veins and Soils in Parts of Maru Schist Belt Area, Northwestern Nigeria

2014 ◽  
Vol 2014 ◽  
pp. 1-17 ◽  
Author(s):  
Samson Adeleke Oke ◽  
Akinlolu Festus Abimbola ◽  
Dieter Rammlmair
Keyword(s):  
Gold Content ◽  
X Ray Diffraction ◽  
Geochemical Characterization ◽  
X Ray ◽  
Quartz Veins ◽  
Magmatic Fluids ◽  
Geochemical Association ◽  
Ore Minerals ◽  
Gold Bearing

Epigenetic, N-S, NNE-SSW quartz veins crosscut metapelites and metagabbro in Maru area. The objectives of this work were to study field, mineralogy, and geochemical characteristics of gold bearing quartz veins and soils. Euhedral and polygonal magnetite with hematite constituted the major ore minerals. Quartz occurred as main gangue phase with appreciable sericite and chlorite. The mineralogy of soil retrieved from twelve minor gold fields examined with X-ray diffraction is quartz ± albite ± microcline ± muscovite ± hornblende ± magnetite ± illite ± kaolinite ± halloysite ± smectite ± goethite ± vermiculite ± chlorite. The concentration of gold in quartz vein varies from 10.0 to 6280.0 ppb with appreciable Pb (3.5–157.0 ppm) and ΣREE (3.6 to 82.9 ppm). Gold content in soil varies from <5.0 to 5700.0 ppb. The soil is characterized by As ± Sb gold’s pathfinder geochemical association. Multidata set analysis revealed most favourable areas for gold. Possibility of magmatic fluids as part of ore constituents is feasible due to presence of several intrusions close to quartz veins. Based on field, mineralogical, and geochemical evidences, ore fluids may have been derived from fracturing, metamorphic dewatering, crustal devolatilization of sedimentary, gabbroic protoliths, and emplaced in an orogenic setting.

scholarly journals Catalytic Activity of Zr4+/ZA on The Isomerization Reaction of α-Pinene and It’s Reusability Test

2016 ◽  
Vol 1 (3) ◽  
pp. 157
Author(s):  
Nico Aditya Wijaya ◽  
Nanik Wijayati ◽  
Edy Cahyono
Keyword(s):  
Natural Zeolite ◽  
Raw Materials ◽  
Batch Reactor ◽  
Gravimetric Method ◽  
Isomerization Reaction ◽  
X Ray ◽  
Bet Method ◽  
Main Component

Production of turpentine oil from pine resin until December 2014<sup>th</sup> was reported to reaching 17.150 tones with the wide of pine forest is 876.992,66 acres. The main component of turpentine oil is α-pinena which isomer products have high value for industrial raw materials. Effects concentration of impregnation and reusability test a best catalyst on α-pinene isomerization reaction using catalysts Zr<sup>4+</sup>/natural zeolite in which modificated with different Zr<sup>4+</sup> concentration were analyzed. Characterization of catalyst included <em>X-ray Fluoroscent </em>for detection of Zr concentration in natural zeolites, <em>Surface Area Analyzer </em> for determine catalyst porosity using BET method, and determination of acidity using vapor ammonia and pyridine base adsorption gravimetric method. Isomerization process used a batch reactor with variation in the concentrations of Zr<sup>4+</sup> impregnations 10, 15, and 20 w/w as well as reusability test used best catalyst. The highest conversion of α-pinene  used Zr<sup>4+</sup>/ZA 10% catalyst was 3,89% so as Zr<sup>4+</sup>/ZA 10% catalyst is best catalyst than other catalysts whereas highest conversion of α-pinene used Zr<sup>4+</sup>/ZA 10% regeneration catalyst was 4,26%. The product is produced from isomerization reaction of α-pinene used Zr<sup>4+</sup>/ZA all variations catalysts was camphene and limonene.

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