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Maria A Lilli, Nikolaos P Nikolaidis, George P Karatzas, Nicolas Kalogerakis
A laboratory study was conducted to assess the mobility and mechanisms of chromium release from soils obtained from an area of wide spread geogenic contamination. The agricultural soil sample used in this study was taken from the Schimatari area in Asopos River basin in Greece. In order to refine the isolation of minerals contained in the soil, two types of separation analysis were conducted. First, a size fractionation with hydrocyclone and second, a weight fractionation with heavy liquids. The separated fractions were characterized using chemical, mineralogical and surface analysis...
November 27, 2018: Journal of Hazardous Materials
Francesco Sauro, Martina Cappelletti, Daniele Ghezzi, Andrea Columbu, Pei-Ying Hong, Hosam Mamoon Zowawi, Cristina Carbone, Leonardo Piccini, Freddy Vergara, Davide Zannoni, Jo De Waele
Chemical mobility of crystalline and amorphous SiO2 plays a fundamental role in several geochemical and biological processes, with silicate minerals being the most abundant components of the Earth's crust. Although the oldest evidences of life on Earth are fossilized in microcrystalline silica deposits, little is known about the functional role that bacteria can exert on silica mobility at non-thermal and neutral pH conditions. Here, a microbial influence on silica mobilization event occurring in the Earth's largest orthoquartzite cave is described...
December 4, 2018: Scientific Reports
Marzougui Salem, Radhia Souissi, Fouad Souissi, Noureddine Abbes, Jacques Moutte
The present study was carried out to show the potential in heavy metals (HM) and the rare earth elements (REE) which presents the residues of phosphoric-acid(PA) purification. Three different cadmiferous solid residues (according to the nature of the purification process of the PA: BG, BC and BS) were collected from an industrial site located in the south of Tunisia. The mineralogical study showed the predominance of anhydrite, accompanied by quartz, malladrite; calcium sulfate hemihydrate and fluorapophyllite...
January 2019: Waste Management
Sarah P Slotznick, Nicholas L Swanson-Hysell, Erik A Sperling
Terrestrial environments have been suggested as an oxic haven for eukaryotic life and diversification during portions of the Proterozoic Eon when the ocean was dominantly anoxic. However, iron speciation and Fe/Al data from the ca. 1.1-billion-year-old Nonesuch Formation, deposited in a large lake and bearing a diverse assemblage of early eukaryotes, are interpreted to indicate persistently anoxic conditions. To shed light on these distinct hypotheses, we analyzed two drill cores spanning the transgression into the lake and its subsequent shallowing...
December 3, 2018: Proceedings of the National Academy of Sciences of the United States of America
Jian Zhang, Wei Li, Ying Li, Lixiang Zhou, Yeqing Lan
Schwertmannite (SCH) has strong adsorption ability to As(III). However, there are few reports on the stability of SCH load with As(III) (SCH-As(III)). In this study, the effects of tartaric acid (TA), pH and coexisting ions including K+ , Ca2+ , Al3+ and CO3 2- on the photoreductive dissolution of SCH- As(III) and the release of the adsorbed As (III) were investigated. The results showed that under UV irradiation TA could greatly enhance the release of total Fe and total As from SCH-As(III). Nevertheless, the total Fe and total As in the solution decreased when TA was consumed up...
November 19, 2018: Environmental Pollution
Marie Catherine Sforna, Daniele Brunelli, Céline Pisapia, Valerio Pasini, Daniele Malferrari, Bénédicte Ménez
Thermodynamic modeling has recently suggested that condensed carbonaceous matter should be the dominant product of abiotic organic synthesis during serpentinization, although it has not yet been described in natural serpentinites. Here we report evidence for three distinct types of abiotic condensed carbonaceous matter in paragenetic equilibrium with low-temperature mineralogical assemblages hosted by magma-impregnated, mantle-derived, serpentinites of the Ligurian Tethyan ophiolite. The first type coats hydroandraditic garnets in bastitized pyroxenes and bears mainly aliphatic chains...
November 28, 2018: Nature Communications
Iván Fernando Macías-Quiroga, Gloria Inés Giraldo-Gómez, Nancy Rocío Sanabria-González
This paper presents a mineralogical and physicochemical characterization of a Colombian clay found in an area with the greatest exploitation potential of smectites and possible use as an adsorbent for the removal of chromium. The clay was characterized by using X-ray diffraction (XRD), cation exchange capacity (CEC), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FT-IR), thermal analysis (TGA/DSC), and nitrogen adsorption at 77 K. The homoionized clay was used as an adsorbent for the removal of Cr(III) in an aqueous solution...
2018: TheScientificWorldJournal
Jan-Martin Wolter, Katja Schmeide, Stephan Weiss, Frank Bok, Vinzenz Brendler, Thorsten Stumpf
The stability of calcium silicate hydrate (C-S-H) gel doped with uranium to form calcium uranium silicate hydrate (C-U-S-H) gel was investigated in 2.5 M NaCl, 2.5 M NaCl/0.02 M Na2 SO4 , 2.5 M NaCl/0.02 M NaHCO3 or 0.02 M NaHCO3 solutions relevant to the geological disposal of radioactive waste. The C-U-S-H gel samples were synthesized by direct U(VI) incorporation and characterized with time-resolved laser-induced luminescence spectroscopy (TRLFS), infrared (IR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA)...
November 14, 2018: Chemosphere
Erika J Espinosa-Ortiz, Brian H Eisner, Dirk Lange, Robin Gerlach
Infection stones are complex aggregates of crystals amalgamated in an organic matrix that are strictly associated with urinary tract infections. The management of patients who form infection stones is challenging owing to the complexity of the calculi and high recurrence rates. The formation of infection stones is a multifactorial process that can be driven by urine chemistry, the urine microenvironment, the presence of modulator substances in urine, associations with bacteria, and the development of biofilms...
November 23, 2018: Nature Reviews. Urology
Zdzisław M Migaszewski, Agnieszka Gałuszka, Sabina Dołęgowska
The Wiśniówka rock strip mining area (south-central Poland) with quartzite quarries, acid water bodies and tailings piles is one of the most unique acid mine drainage (AMD) sites throughout the world. This is due to the occurrence of enormous amounts of pyrite unknown in sedimentary formations worldwide. Of the two mineralization zones, one that is the most abundant in arsenical pyrite occurs in the lowermost Upper Cambrian formation of the Podwiśniówka quarry. The As-rich pyritiferous clastic rocks are exposed as a result of deep quartzite extraction during 2013-2014...
January 2019: Environmental Pollution
Neha Mehta, Tatiana Cocerva, Sabrina Cipullo, Elio Padoan, Giovanna Antonella Dino, Franco Ajmone-Marsan, Siobhan Fiona Cox, Frederic Coulon, Domenico Antonio De Luca
Oral bioaccessibility and solid phase distribution of potentially toxic elements (PTE) from extractive waste streams were investigated to assess the potential human health risk posed by abandoned mines. The solid phase distribution along with micro-X-ray fluorescence (micro-XRF) and scanning electron microscopy (SEM) analysis were also performed. The results showed that the total concentrations of PTE were higher in <250 μm size fractions of waste rock and soil samples in comparison to the <2 mm size fractions...
February 15, 2019: Science of the Total Environment
Soroush Modabberi
Muteh Gold Deposit is the biggest active gold district in Iran consisting of two mines, Senjedeh and Chah-Khatoun, and seven mineral occurrences. Senjedeh has been mined about 20 years ago and was recently closed because of the depletion of the reserves. Chah-Khatoun went into operation few years ago. During the previous decades, more than 22 Mt of low-grade wastes has been produced from both mines. The wastes are assumed to be a possible source of gold, especially with recent increase in the world gold prices...
November 19, 2018: Environmental Monitoring and Assessment
Ngoc Hung Le, Andry Razakamanantsoa, Mai-Lan Nguyen, Van Tien Phan, Phuc-Lam Dao, Dang Hanh Nguyen
Municipal Solid Waste Incinerator (MSWI) Bottom Ash has been used as a substitute for traditional aggregates in road construction; however, this material is little understood. The work presented in this paper pursues the study on the mechanical performance of bottom ash, proven by Le et al. (2017). Using a coupling technique for the first time, the physicochemical aspects and hydromechanical resistance of bottom ash were evaluated and analyzed. Physicochemical tests were first carried out, followed by oedometer tests under a wetting path...
October 2018: Waste Management
Mung-Chung Kao, Adrian F Pegoraro, David M Kingston, Albert Stolow, Wen-Chuan Kuo, Patrick H J Mercier, Ankur Gogoi, Fu-Jen Kao, Andrew Ridsdale
Multi-modal nonlinear optical (NLO) microscopy, including stimulated Raman scattering (SRS) and second harmonic generation (SHG), was used to directly image mineralogical features of economic ore and rock samples. In SRS/SHG imaging, ore samples generally require minimal preparation and may be rapidly imaged, even in their wet state. 3D structural details, at submicron resolution, are revealed tens of microns deep within samples. Standard mineral imaging based on scanning electron microscopy (SEM), with elemental analysis via energy dispersive X-Ray spectroscopy, was used to independently validate the mineral composition of the samples...
November 16, 2018: Scientific Reports
Daria Jóźwiak-Niedźwiedzka, Michał A Glinicki, Karolina Gibas, Tomasz Baran
Long-term exposure of concrete to nuclear reactor environments may enhance the ageing phenomena. An investigation concerning a possible deleterious alkali-silica reaction (ASR) in concrete containing high-density aggregates is presented in this paper. The scope of this investigation was limited to heavy aggregates that could be used for the construction of the first Polish nuclear power plant (NPP). Five different high-density aggregates were selected and tested: three barites, magnetite, and hematite. Mineralogical analysis was conducted using thin section microscopic observation in transmitted light...
November 15, 2018: Materials
Teemu Karlsson, Marja Liisa Räisänen, Marja Lehtonen, Lena Alakangas
Acid rock drainage (ARD) is a major problem related to the management of mining wastes, especially concerning deposits containing sulphide minerals. Commonly used tests for ARD prediction include acid-base accounting (ABA) tests and the net acid generation (NAG) test. Since drainage quality largely depends on the ratio and quality of acid-producing and neutralising minerals, mineralogical calculations could also be used for ARD prediction. In this study, several Finnish waste rock sites were investigated and the performance of different static ARD test methods was evaluated and compared...
November 13, 2018: Environmental Monitoring and Assessment
Cong Fan, Chuling Guo, Meiqin Chen, Weilin Huang, Jingjing Wan, John R Reinfelder, Xiaofei Li, Yufei Zeng, Guining Lu, Zhi Dang
Schwertmannite is an important sink for cadmium (Cd) in acid mine drainage (AMD) environments and is unstable when environmental conditions change. However, the release and redistribution of Cd during schwertmannite transformation with respect to pre-bound Cd are poorly understood. In this work, the transformation of cadmium-associated schwertmannite and subsequent Cd repartitioning behaviors were investigated. The way of schwertmannite associated with Cd was predominant by absorption, and the diffuse layer model (DLM) showed that Cd2+ existed as monodentate complexes ≡Fe(1) OCd+ and ≡Fe(2) OCd+ on schwertmannite surfaces...
November 8, 2018: Environmental Science and Pollution Research International
Bas Vriens, Holly Peterson, Laura Laurenzi, Leslie Smith, Celedonio Aranda, K Ulrich Mayer, Roger D Beckie
The weathering of mine waste rock can cause release of metal-laden and acidic drainage that requires long-term and costly environmental management. To identify and quantify the geochemical processes and physical transport mechanisms controlling drainage quality, we monitored the weathering of five large-scale (20,000 t) instrumented waste-rock piles of variable and mixed-composition at the Antamina mine, Peru, in a decade-long monitoring program. Fine-grained, sulfidic waste rock with low-carbonate content exhibited high sulfide oxidation rates (>1 g S kg-1 waste rock yr-1 ) and within 7 years produced acidic (pH < 3) drainage with high Cu and Zn concentrations in the g L-1 range...
January 2019: Chemosphere
D O Gimranov, V G Kotov, M M Rumyantsev, V I Silaev, A G Yakovlev, T I Yakovleva, N V Zelenkov, M V Sotnikova, M M Devyashin, N A Plasteeva, N E Zaretskaya, I M Nurmukhametov, N G Smirnov, P A Kosintsev
The vertebrate fauna from the cave deposits in Imanai Cave in the Southern Urals (53°02' N, 56°26'E) has been studied. It contains 715 bones that belonged to at least 11 individuals of fossil lion (Panthera (Leo) ex gr. fossilis-spelaea). It has been established that this is one of the largest Eurasian burial sites of fossil lions. The bones were accumulated due to the natural death of animals inside the cave. The age and sex estimations have shown that at least six adult males and five adult females died there...
September 2018: Doklady Biological Sciences: Proceedings of the Academy of Sciences of the USSR, Biological Sciences Sections
Teresa Fornaro, Andrew Steele, John Robert Brucato
Minerals might have played critical roles for the origin and evolution of possible life forms on Mars. The study of the interactions between the "building blocks of life" and minerals relevant to Mars mineralogy under conditions mimicking the harsh Martian environment may provide key insight into possible prebiotic processes. Therefore, this contribution aims at reviewing the most important investigations carried out so far about the catalytic/protective properties of Martian minerals toward molecular biosignatures under Martian-like conditions...
November 5, 2018: Life
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