Starch Graft Polymers. III. Preparation of Graft Polymers Containing Acrylamide, Acrylic Acid and β-Methacryloyloxyethyltrimethylammonium Monomethyl Sulfate and Evaluation as Flocculants for Bauxite Ore Red Mud Suspensions

1973 ◽  
Vol 25 (3) ◽  
pp. 83-89 ◽  
Author(s):  
D. A. Jones ◽  
L. F. Elmquist
Keyword(s):  
Acrylic Acid ◽  
Red Mud ◽  
Graft Polymers ◽  
Bauxite Ore

scholarly journals Radiation-Induced Asymmetric Grafting of Different Monomers into Base Films to Prepare Novel Bipolar Membranes

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2028
Author(s):  
Shin-ichi Sawada ◽  
Yasunari Maekawa
Keyword(s):  
Acrylic Acid ◽  
Anion Exchange ◽  
Graft Polymerization ◽  
The Other ◽  
Practical Applications ◽  
Bipolar Membranes ◽  
Graft Polymers ◽  
Grafting Reactions ◽  
Radiation Induced

We prepared novel bipolar membranes (BPMs) consisting of cation and anion exchange layers (CEL and AEL) using radiation-induced asymmetric graft polymerization (RIAGP). In this technique, graft polymers containing cation and anion exchange groups were introduced into a base film from each side. To create a clear CEL/AEL boundary, grafting reactions were performed from each surface side using two graft monomer solutions, which are immiscible in each other. Sodium p-styrenesulfonate (SSS) and acrylic acid (AA) in water were co-grafted from one side of the base ethylene-co-tetrafluoroethylene film, and chloromethyl styrene (CMS) in xylene was simultaneously grafted from the other side, and then the CMS units were quaternized to afford a BPM. The distinct SSS + AA- and CMS-grafted layers were formed owing to the immiscibility of hydrophilic SSS + AA and hydrophobic CMS monomer solutions. This is the first BPM with a clear CEL/AEL boundary prepared by RIAGP. However, in this BPM, the CEL was considerably thinner than the AEL, which may be a problem in practical applications. Then, by using different starting times of the first SSS+AA and second CMS grafting reactions, the CEL and AEL thicknesses was found to be controlled in RIAGP.

Assessment of Naturally Occurring Radioactive Materials (NORM) in Mining Residues and Environmental Material from Sefwi, Awaso Bauxite Mine

2021 ◽  
Author(s):  
Matjele Moipone ◽  
Oscar K. Adukpo ◽  
Joseph B. Tandoh
Keyword(s):  
Effective Dose ◽  
Water Samples ◽  
Red Mud ◽  
Gamma Ray ◽  
Gamma Ray Spectrometry ◽  
Activity Levels ◽  
Environmental Material ◽  
Bauxite Ore ◽  
Mining Residues ◽  
Bauxite Mine

Abstract Gamma ray spectrometry was used to quantify level of NORM in mining residues sampled at Awaso bauxite mine and surrounding communities. The radionuclides of interest were 238U, 232Th and 40K and the radioactivity levels were determined in soil, bauxite ore, red mud and water samples from wells. The radioactivity concentrations in soil, bauxite ore and red mud 238U, 232Th and 40K were 18.01±1.96 Bqkg-1, 19.07±2.12 Bqkg-1 and 103.21±1.74 Bqkg-1; 39.42±4.18 Bqkg-1, 97.32±10.63 Bqkg-1 and 14.68±1.82 Bqkg-1; 44.85±4.79, 64.23±6.58 and 125.30±18.72 Bqkg-1. The activity levels for both 232U and 232Th were above world-wide average values while Potassium-40 levels were lower. The mean activity concentration values of 238U, 232Th and 40K in water samples were 1.49±0.45 Bql-1, 3.68±0.69 Bql-1 and 15.69±0.28 Bql-1 respectively and were within the world average activity concentrations except for bauxite ore and red mud. The committed effective dose was 0.74 mSv and annual effective dose estimated to be 0.136 mSv which is below recommended dose limit of 1 mSvyear-1 for public exposure.

Effect of Calcined Red Mud Addition on the Hydration of Portland Cement

2012 ◽  
Vol 727-728 ◽  
pp. 1408-1411 ◽  
Author(s):  
Daniel Véras Ribeiro ◽  
João A. Labrincha ◽  
Márcio Raymundo Morelli
Keyword(s):  
Portland Cement ◽  
Red Mud ◽  
Setting Time ◽  
Cementitious Materials ◽  
Adiabatic Calorimeter ◽  
Hydration Process ◽  
Early Hydration ◽  
Bauxite Ore ◽  
Calorimetric Studies ◽  
Reference Mixture

The red mud (RM) is a solid waste derived from the processing of bauxite ore to produce alumina and it is considered a hazardous waste due to its high pH. This paper describes the use of mud untreated and after calcination at distinct temperatures (450, 650, and 1000°C) attempting to improve its reactivity. The Portland cement was replaced up to 30 wt% red mud, and its addition changed the hydration process, evaluated by calorimetric studies of early hydration and setting time. By comparing with the reference mixture (without red mud), the obtained results confirm the potential of the red mud to be used as pozzolanic additive to cementitious materials. Temperature of hydration was monitored by a quasi-adiabatic calorimeter (Langavant). The hydration temperature increases with RM addition, particularly if calcined in the same interval (450-650°C). In this condition, the hydration process is accelerated.

scholarly journals Effect of red mud addition on the corrosion parameters of reinforced concrete evaluated by electrochemical methods

2012 ◽  
Vol 5 (4) ◽  
pp. 451-467 ◽  
Author(s):  
D.V. Ribeiro ◽  
J.A. Labrincha ◽  
M.R. Morelli
Keyword(s):  
Electrical Resistivity ◽  
Reinforced Concrete ◽  
Red Mud ◽  
Corrosion Potential ◽  
Corrosion Process ◽  
Bayer Process ◽  
Alumina Production ◽  
High Ph ◽  
High Electrical Resistivity ◽  
Bauxite Ore

Red mud, the main waste generated in aluminum and alumina production from bauxite ore by the Bayer process, is considered "hazardous" due to its high pH. The high pH also provides greater protection of rebars, which is reflected in the low corrosion potential and high electrical resistivity (filler effect) of concrete. The corrosion potential was monitored by electrochemical measurements and the electrical resistivity was evaluated using sensors embedded in concrete test specimens. The results showed that the addition of red mud is beneficial to concrete, reducing its corrosion potential and increasing its electrical resistivity. Red mud proved to be a promising additive for concrete to inhibit the corrosion process.

scholarly journals Removal of Pb ion from water samples using red mud (bauxite ore processing waste)

2013 ◽  
Vol 1 ◽  
pp. 41019 ◽  
Author(s):  
A. Ghorbani ◽  
M. Nazarfakhari ◽  
Y. Pourasad ◽  
S. Mesgari Abbasi
Keyword(s):  
Water Samples ◽  
Red Mud ◽  
Processing Waste ◽  
Ore Processing ◽  
Bauxite Ore

scholarly journals Synthesis of Amorphous Aluminosilicates from Bintan’s Red Mud as Alumina Source

2018 ◽  
Vol 18 (4) ◽  
pp. 580
Author(s):  
Futri Wulandari ◽  
Eka Putra Ramdhani ◽  
Yatim Lailun Ni’mah ◽  
Ahmad Anwarud Dawam ◽  
Didik Prasetyoko
Keyword(s):  
Red Mud ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Structure Directing Agent ◽  
Alumina Production ◽  
Hydrolysis Method ◽  
Alkali Fusion ◽  
Silica Source ◽  
Bauxite Ore ◽  
Adsorption Desorption

Red mud is a generated by-product in alumina production from bauxite ore. In this study, Bintan’s red mud has been used as alumina and silica source to synthesize amorphous mesoporous aluminosilicates material. Alkali fusion method with a NaOH/red mud ratio 0.8; 1.0; 1.2; 1.4 and 1.5 followed by hydrolysis method was used to extract dissolved alumina and silica from red mud. Synthesis of amorphous aluminosilicates by hydrothermal method was conducted at 80 °C for 24 h. Cetyltrimethylammonium bromide (CTABr) was added as the structure directing agent. Aluminosilicate products were characterized using FTIR spectroscopy (Fourier Transform Infra-Red Spectroscopy), XRD (X-ray Diffraction), SEM (Scanning Electron Microscopy), and nitrogen adsorption-desorption. XRD and SEM result shows that the product was amorphous with low uniformity in terms of surface morphology and particle size. Nitrogen adsorption-desorption profile shows that all aluminosilicates products has a meso pore structure, confirmed by the highest pore distribution at 3.05–17.70 nm. The highest surface area and pore volume were obtained in ASM 0.8 (NaOH/red mud ratio = 0.8) i.e. 177.97 m2/g and 1.09 cm3/g, respectively.

scholarly journals Bulk Utilization of Red Mud in Geopolymer Based Products

2020 ◽  
Vol 12 (2) ◽  
pp. 86-91
Author(s):  
Abhisek Mohapatra ◽  
Prasanta Bose ◽  
Sagar S Pandit ◽  
Sanjay Kumar ◽  
T.C. Alex
Keyword(s):  
Red Mud ◽  
Ash Content ◽  
Target Strength ◽  
Alkali Concentration ◽  
Alumina Production ◽  
Ore Processing ◽  
Fine Size ◽  
Bauxite Ore ◽  
Alumina Industry ◽  
And Storage

Red Mud is the solid residue generated from Alumina refinery during the process of bauxite ore processing through Bayer’s process. Typical generation of red mud is 1.5 tons of red mud per ton of alumina produced. The disposal and storage of red mud has been a concern for the alumina industry since its inception, more than a hundred years ago. With the increase in alumina production, the magnitude of the problem is getting multiplied. Its alkaline nature (Na2O ~ 3-7%) and fine size make red mud unsuitable for many applications; a limited utilization is reported in cement industries as one of the raw mix components for cement. The present work deals with the utilization of red mud in geopolymer based paving blocks. Alumina, silica and alkali are the essential items required for geopolymer preparation. Having all these in red mud, the current study attempted to use the same in geopolymer based products. The focus has been on bulk utilization of red mud; target strength of 20 MPa after 28 days of curing (M20 grade) has been the goal as this strength is sufficient for many applications. The study focused on optimizing the red mud content, alkali concentration, fly ash content, etc. The samples are tested for its compressive strength and leachability. The study reveals that significant amount of red mud incorporation is possible with products conforming to USEPA 1311 norms.

X-ray Diffraction and Thermal Analysis of Bauxite Ore-Processing Waste (Red Mud) Exchanged with Arsenate and Phosphate

2011 ◽  
Vol 59 (2) ◽  
pp. 189-199 ◽  
Author(s):  
Paola Castaldi ◽  
Margherita Silvetti ◽  
Stefano Enzo ◽  
Salvatore Deiana
Keyword(s):  
Thermal Analysis ◽  
Red Mud ◽  
Processing Waste ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ore Processing ◽  
Bauxite Ore

scholarly journals Influence of Na2CO3 and K2CO3 Addition on Iron Grain Growth during Carbothermic Reduction of Red Mud

Metals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1313 ◽  
Author(s):  
Dmitry Zinoveev ◽  
Pavel Grudinsky ◽  
Andrey Zakunov ◽  
Artem Semenov ◽  
Maria Panova ◽  
...  
Keyword(s):  
Magnetic Separation ◽  
Grain Growth ◽  
Red Mud ◽  
Carbothermic Reduction ◽  
Reduction Roasting ◽  
Alumina Production ◽  
Iron Aluminum ◽  
Bauxite Ore ◽  
Hsc Chemistry ◽  
Sodium And Potassium

Red mud is a by-product of alumina production from bauxite ore by the Bayer method, which contains considerable amounts of valuable components such as iron, aluminum, titanium, and scandium. In this study, an approach was applied to extract iron, i.e., carbothermic reduction roasting of red mud with sodium and potassium carbonates followed by magnetic separation. The thermodynamic analysis of iron and iron-free components’ behavior during carbothermic reduction was carried out by HSC Chemistry 9.98 (Outotec, Pori, Finland) and FactSage 7.1 (Thermfact, Montreal, Canada; GTT-Technologies, Herzogenrath, Germany) software. The effects of the alkaline carbonates’ addition, as well as duration and temperature of roasting on the iron metallization degree, iron grains’ size, and magnetic separation process were investigated experimentally. The best conditions for the reduction roasting were found to be as follows: 22.01% of K2CO3 addition, 1250 °C, and 180 min of duration. As a generalization of the obtained data, the mechanism of alkaline carbonates’ influence on iron grain growth was proposed.

scholarly journals Review of the Valorization of Normalized Red Mud as Environmentally Sustainable Waste Management

2021 ◽  
pp. 57-69
Author(s):  
Siba Prasad Mishra ◽  
Madhurima Das ◽  
Saswat Mishra
Keyword(s):  
Red Mud ◽  
Large Scale ◽  
Ceramic Materials ◽  
Waste Valorization ◽  
Environmentally Sustainable ◽  
Indian Context ◽  
Large Numbers ◽  
High Alkalinity ◽  
Bauxite Ore ◽  
Extraction Processes

The Red Mud has focused through major industrial and scientific research in industrial waste valorization. Red mud is the discarded produce of alumina extraction processes from its parent the bauxite ore. Its high alkalinity causes it to be kept in large quantities, resulting in increased deforestation. Annually, it is estimated that 64.2 MMT of red mud wastes are formed around the world, and India produces about 9MMT with less hope of being reused, posing a serious threat of pollution and contamination of both soil, ground water and the environment. Large numbers of research have shown that this bauxite solid waste can be refurbished to make construction bricks, pavement tiles, ceramic materials, but no full large-scale benign re-utilization have been made. The intent of the research is to probe in to the applications of red mud in the construction and various sectors, giving emphasis on Indian context. Other researchers' observations were considered and analyzed in terms of environmental, economic, and technical feasibility to fulfill zero waste demand due to red mud.

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