scholarly journals Reduction in Technogenic Burden on the Environment by Flotation Recovery of Rare Earth Elements from Diluted Industrial Solutions

2021 ◽  
Vol 11 (16) ◽  
pp. 7452
Author(s):  
Natalia Dzhevaga ◽  
Olga Lobacheva
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Building Materials ◽  
Sodium Dodecyl ◽  
Construction Materials ◽  
Distribution Coefficients ◽  
Industrial Plant ◽  
Flotation Recovery ◽  
Industrial Solutions ◽  
The Impact

Unconventional raw materials are widely used in construction sectors; for example, phosphate sludge with the addition of rare earth elements (REE) when producing brick. The second example is nanostructured composite systems of REE when forming covers of construction materials. This article studies flotation recovery of REE, the impact of chlorides on distribution coefficient, and pH recovery. The study proves the possibility of effective REE recovery from diluted industrial solutions and, consequently, the significant decrease in their content in wastewaters, which allows the improvement of the ecological situation in the industrial plant areas. In this article, optimum flotation conditions of REE by flotation are given by the example of yttrium (III) and lanthanum (III) salts. The processes of rare earth elements recovery by sodium dodecyl sulphate as salts of various compositions were studied. Distribution coefficients for target components as a function of aqueous phase pH and the presence of foreign anions were determined. The analysis of dependences obtained by the comparison of rare earth elements’ chloro and hydroxo complexes stability constants was made. The products of REE obtained by the authors will be used when manufacturing various kinds of building materials: carbon cement, baked brick, light construction materials, and high-tensile steel.

scholarly journals Fire Resistance Behaviour of Geopolymer Concrete:An Overview

Buildings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 82
Author(s):  
Salmabanu Luhar ◽  
Demetris Nicolaides ◽  
Ismail Luhar
Keyword(s):  
Compressive Strength ◽  
Thermal Resistance ◽  
Building Materials ◽  
Elevated Temperatures ◽  
Construction Materials ◽  
Flexural Behavior ◽  
Thermal Shrinkage ◽  
Physico Chemical ◽  
The Impact ◽  
Loss Of Strength

Even though, an innovative inorganic family of geopolymer concretes are eye-catching potential building materials, it is quite essential to comprehend the fire and thermal resistance of these structural materials at a very high temperature and also when experiencing fire with a view to make certain not only the safety and security of lives and properties but also to establish them as more sustainable edifice materials for future. The experimental and field observations of degree of cracking, spalling and loss of strength within the geopolymer concretes subsequent to exposure at elevated temperature and incidences of occurrences of disastrous fires extend an indication of their resistance against such severely catastrophic conditions. The impact of heat and fire on mechanical attributes viz., mechanical-compressive strength, flexural behavior, elastic modulus; durability—thermal shrinkage; chemical stability; the impact of thermal creep on compressive strength; and microstructure properties—XRD, FTIR, NMR, SEM as well as physico-chemical modifications of geopolymer composites subsequent to their exposures at elevated temperatures is reviewed in depth. The present scientific state-of-the-art review manuscript aimed to assess the fire and thermal resistance of geopolymer concrete along with its thermo-chemistry at a towering temperature in order to introduce this novel, most modern, user and eco-benign construction materials as potentially promising, sustainable, durable, thermal and fire-resistant building materials promoting their optimal and apposite applications for construction and infrastructure industries.

scholarly journals Susceptibility of earth-based construction materials to fungal proliferation: laboratory and in situ assessment

2019 ◽  
Vol 3 ◽  
pp. 140-149 ◽  
Author(s):  
Alexis Simons ◽  
Alexandra Bertron ◽  
Christophe Roux ◽  
Aurélie Laborel-Préneron ◽  
Jean-Emmanuel Aubert ◽  
...  
Keyword(s):  
Air Quality ◽  
Manufacturing Process ◽  
Building Materials ◽  
Construction Materials ◽  
Microbial Density ◽  
Microbial Proliferation ◽  
Materials Used ◽  
Ecological Construction ◽  
The Impact

The impact of building materials on the environment and the health of occupants is nowadays a priority issue. Ecological construction materials such as earthen materials are currently experiencing a regain of interest due to both ecological and economic factors. The microbial proliferation on indoor materials can induce a deterioration of the building air quality and lead to an increase of health risks for the occupants. The issue of indoor air quality raises questions about the use of earthen building materials and their possible susceptibility to fungal development. The microflora of earthen materials and their ability to grow on such support are indeed poorly studied. This study focused on the quantification of both bacterial and fungal microflora along the manufacturing process. The impact of extreme humidity, simulating a hydric accident, on microflora development was analyzed on the surface and inside earthen bricks. The initial microflora of these materials was dramatically reduced during the manufacturing process, especially after heat treatment for drying. Proliferation of remaining microorganisms was only observed under high humidity condition, in particular for earthen materials with vegetal aggregates. Moreover, in situ samplings were performed on naturally dried earthen materials used in buildings. The characterization of the microbial density revealed a higher microbial density than on manufactured specimens, while microbial concentration and detected taxa seemed mainly related to the room use and building history. These results provide a better understanding of microbial proliferation on these materials.

Chemical and petrochemical industry

2018 ◽  
Vol 3 (4) ◽  
Author(s):  
Katarzyna Staszak
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Petrochemical Industry ◽  
Metal Recovery ◽  
Platinum Group Metals ◽  
Secondary Source ◽  
New Methods ◽  
Metal Contents ◽  
Potential Sources ◽  
Industrial Solutions

Abstract The potential sources of various metals in chemical and petrochemical processes are discussed. Special emphasis is put on the catalysts used in the industry. Their main applications, compositions, especially metal contents are presented both for fresh and spent ones. The focus is on the main types of metals used in catalysts: the platinum-group metals, the rare-earth elements, and the variety of transition metals. The analysis suggested that chemical and petrochemical sectors can be considered as the secondary source of metals. Because the utilization of spent refinery catalysts for metal recovery is potentially viable, different methods were applied. The conventional approaches used in metal reclamation as hydrometallurgy and pyrometallurgy, as well as new methods include bioleaching, were described. Some industrial solutions for metal recovery from spent solution were also presented.

scholarly journals Cretaceous-Paleogene boundary Fish Clay at Højerup (Stevns Klint, Denmark): Zn, Pb and REE in kerogen

2008 ◽  
Vol 73 (4) ◽  
pp. 453-461
Author(s):  
Pavle Premovic ◽  
Maja Stankovic ◽  
Mirjana Pavlovic ◽  
Milos Djordjevic
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Humic Substances ◽  
Rare Earths ◽  
Land Surface ◽  
Coastal Areas ◽  
Previous Hypothesis ◽  
Geochemical Analyses ◽  
The Impact ◽  
Fish Clay

Geochemical analyses of Zn, Pb and rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu) in the kerogen of the black marl at the Cretaceous - Paleogene boundary Fish Clay at H?jerup were performed. Substantial proportions of the Zn, Pb and rare earths were probably contained in terrestrial humic substances (the kerogen precursor) arriving at the marine sedimentary site. This is in accord with a previous hypothesis that kerogen is mainly derived from humic acids of an oxic soil in of the adjacent coastal areas of eastern Denmark. It is also suggested that humics enriched in Zn, Pb and rare earth elements were transported mainly through fluvial transport into the deposition site of the Fish Clay. Local weathering/leaching of the impact-eject fallout on the land surface and local terrestrial rocks by impact-induced? acid surface waters perhaps played an important role in providing Zn, Pb and rare earths to these humic substances. Apparently, chondritic and non-chondritic Zn originated from the impact fallout; Pb and rare earth elements were most likely sourced by exposed rocks in the coastal areas of eastern Denmark.

Variation of the distribution coefficients of rare earth elements in modern coral-lattices: species and site dependencies

2004 ◽  
Vol 68 (10) ◽  
pp. 2265-2273 ◽  
Author(s):  
T Akagi ◽  
Y Hashimoto ◽  
Fu F-F ◽  
H Tsuno ◽  
H Tao ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Distribution Coefficients

Green chemistry and sustainable development: approaches to chemical footprint analysis

2018 ◽  
Vol 90 (1) ◽  
pp. 143-155 ◽  
Author(s):  
Natalia P. Tarasova ◽  
Anna S. Makarova ◽  
Stanislav F. Vinokurov ◽  
Vladimir A. Kuznetsov ◽  
Pavel I. Shlyakhov
Keyword(s):  
Heavy Metals ◽  
Sustainable Development ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Regional Scale ◽  
Small Water ◽  
Federal Districts ◽  
Footprint Analysis ◽  
Development Goals ◽  
The Impact

AbstractThe methods to monitor the distribution of chemicals in the biosphere and to estimate the impact of chemicals on the biosphere are necessary to reach Sustainable Development Goals (SDGs). The paper presents the examples of methods to measure the concentration of heavy metals (including rare earth elements) and to rank them by the level of hazard to human health on different scales. The megacity scale presents the investigation of the impact of heavy metals on the small water bodies using water contamination index (WCI); and the investigation of snow contamination to estimate the level of short-term seasonal emission of heavy metals and rare earth elements. The 2nd part of the paper presents approaches to mitigate the exposure to mercury on the regional scale: the estimation of the current concentrations of mercury in atmospheric air, natural soils, and fresh waters using UNEP/SETAC USEtox model, as well as the estimations of the variations in the concentrations of mercury for the year 2045 in the federal districts of the Russian Federation, based on representative concentration pathways (RCPs) scenario and Minamata Convention scenario.

scholarly journals INTERNATIONAL TRENDS AND CURRENT CHALLENGES OF CONSTRUCTION MATERIALS MARKET DEVELOPMENT

2020 ◽  
Author(s):  
Yulia Orlovska ◽  
◽  
Daria Havrylenko ◽  
Keyword(s):  
Real Estate ◽  
Construction Industry ◽  
Information And Communication Technologies ◽  
Building Materials ◽  
Construction Materials ◽  
Construction Sector ◽  
International Trends ◽  
The World ◽  
The Impact ◽  
Construction Services

The main international trends in the world market of construction materials and services have been analyzed. The dynamics of world GDP and exports of construction services for the period 2000-2019 has been studied and a conclusion is made on the impact of economic crises on their growth rates. It has been determined that the dynamics of world exports of construction services is characterized by high instability with peaks of growth and decline, and is more sensitive than GDP growth. It has been noted that overcoming the crisis in the export sector of construction services takes more time and occurs with an approximate two-year time lag compared to GDP dynamics. The share of the construction industry in the world GDP by the degree of development has been analyzed. The reasons for the decline in the share of the construction industry in countries with economies in transition have been substantiated. It has been noted that in the developed countries the share of the construction sector is accounted for by real estate management activities related to maintenance, rent, purchase and sale and other transactions with land and real estate. The forecast values of growth of the market of building materials and services till 2030 have been given. The essence of the term «wide construction» has been revealed and the structure of this sector in different countries of the world is shown. The main exporters in the world construction market have been given and the structural distribution of the largest construction companies in the world ranking by country of origin has been analyzed. The dynamics of income level in the construction industry market for the period 2011-2018 has been studied. It has been noted that an important area of the construction sector is the market of roofing and facade materials and the world's largest companies for the production of this type of construction materials have been revealed. Conclusions on the essence of global transformations of the market of building materials and services have been made, and also it has been defined that they are caused by transnationalization of corporate structure of the market, influence of scientific and technical progress and information and communication technologies on world centers as well as the emergence of the concept of «sustainable construction» in the course of humanity for sustainable development.

scholarly journals Geo-Environmental investigation of Sahure pyramid complex, Abusir Archeological site, Giza, Egypt

2021 ◽  
Author(s):  
Abdelrhman Muhamed Fahmy Sayed Ahmed ◽  
Fatma Muhamed Helmy
Keyword(s):  
Building Materials ◽  
Construction Materials ◽  
Polarized Light ◽  
Archaeological Site ◽  
Field Studies ◽  
Point Of View ◽  
Western Side ◽  
The Impact ◽  
Archeological Site ◽  
Engineering Stability

Abstract Abusir is the name of an elaborate burial area, dotted with 19 pyramids other temples, stretching on the western side of the Nile from the south of the Giza Plateau to the northern rim of Saqqara. It seems to have been created as the resting site for the Pharaos dated from 2494 to 2345 BC. The name Abusir, originally spoken as Busiri, means” temple of Osiris”. Over time, the name has become so popular, that more than 60 villages now carry this name. But only one is the archaeological site. This paper does not refer to all of the Abusir archaeological area, but focuses one of its most important sites: Sahure pyramid, one of Egypt’s little known, but heavily damaged treasure. One of the highlights of the relevant research is the discovery of a piece of cement (Basaltic mortar/concrete), which consists of several materials and which is harder than any cement produced today and detection of a clear and significant Anorthite mineral (Plagioclase) in the mortar sample which had been proven by XRD, XRF (analysis) and Polarized light microscope (investigation). The main objectives of this paper are 1) to reveal and identify the construction materials of the pyramid and the construction of the pyramid,2) to evaluate the durability and vulnerability of the Ancient construction materials of Sahure pyramid,3) to compare the decayed patterns of the different construction materials, 4) to study the pyramid building materials from geological, meteorological, geochemical, petrological and petrophysical point of view, and 5) to present a proposal for scientific conservation and protection of the pyramid. Laboratories and field studies have been carried out by researchers from various countries to investigate and understand the problems of the pyramid leading to the final results which confirmed the impact of the geo environment conditions on the structural and engineering stability of the pyramid.

scholarly journals Increasing the depth of apatite processing by extracting rare-earth elements

2021 ◽  
Vol 266 ◽  
pp. 02002
Author(s):  
E.S. Lukyantseva ◽  
V.V. Sergeev
Keyword(s):  
Rare Earth ◽  
Phosphoric Acid ◽  
Rare Earth Elements ◽  
Extraction Process ◽  
Extractant Concentration ◽  
Wet Process ◽  
Heavy Rare Earth Elements ◽  
Knowledge Intensive ◽  
The Impact ◽  
Method Of Extraction

Currently, most high-technology productions are impossible without rare-earth elements (REE). The heavy rare-earth elements are of great interest as they have the highest market value and are in demand in the vast majority of knowledge-intensive industries. The main recourse of REE in Russia is apatite ore which is used in the production of fertilizers. As a result of its leaching, about 15-20% of REE goes to wet-process phosphoric acid. To enhance the depth of apatite processing, it is necessary to develop a technology which will allow obtaining rare-earth elements as by-products. The method of extraction and concentration of REE discussed in this paper was conducted by using the extractant based on di-(2-ethylhexyl) phosphoric acid (D2EHPA). The mechanism of extraction was studied, as well as the impact of the extractant concentration, phase ratio and the number of stages on the extraction process.

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