CHANGING TECHNOLOGY Ln a CHANGING WORLD the CASE of EXTRACTIVE METALLURGY 1
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Study on New Desilication Technology of High Silica Bauxite
2016 2nd International Conference on Sustainable Energy and Environmental Engineering (SEEE 2016) ISBN: 978-1-60595-408-0 Study on New Desilication Technology of High Silica Bauxite Hai-yun XIE 1, Chao DING 1, Peng-fei ZHANG 1,2 , Lu-zheng CHEN 1, and Xiong-TONG 1 1Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China 2State Key Laboratory of Complex Nonferrous Metal Resource Clean Utilization, Kunming 650093, China Keywords: High silicon bauxite, Desilication, Gravity separation, Froth flotation. Abstract: There are abundant diasporic bauxite resource in China. The gravity separation and flotation process are utilized for treating this kind of ore. When the ore grinding fineness is -200 mesh 80%, the qualified bauxite concentrate can be obtained, and it contains Al 2O3 71.62%, SiO 2 8.94%, and its Al 2O3 recovery rate is 75.43%, A/S is 8.02.Compared with single flotation process, it can be reduced for the dosage flotation reagent and the cost of mineral processing. Introduction China's bauxite resources are rich, the amount of resources of 1.914 billion, ranking the fifth in the world, but more than 80% are medium and low grade ore, Aluminum silicon ratio (A/S) between 4 to 7 of the bauxite accounted for 59.5%. These minerals can not meet the basic conditions for the production of alumina by Bayer process. (A/S>8) [1]. The vast majority of China's bauxite belong to high-alumina, high-silicon, fine-grained embedded diaspore-type bauxite, so the bauxite is difficult to concentrate. -
GREEN SYNTHESIS and CHARACTERIZATION of SODIUM Supported by CYANIDE from CASSAVA (Manihot Esculenta CRANTZ)
GREEN SYNTHESIS AND CHARACTERIZATION OF SODIUM Supported by CYANIDE FROM CASSAVA (Manihot esculenta CRANTZ) E. B. AttahDaniel1*, P. O. Enwerem2, P. G. Lawrence1, C. U. Ofiwe 3, S. O. O. Olusunle4 and A. R. Adetunji5 1Department of Chemical Sciences, Federal University Wukari, PMB 1020, Taraba State, Nigeria 2Department of Chemistry, River State University, PMB 5080, Mkpoluorowurukwo, Port Harcourt, Nigeria 3National Agency for Science & Engineering Infrastructure, Centre of Excellence, Nanotechnology and Advanced Material, Akure x, Ondo State, Nigeria 4Engineering Materials Development Institute, PMB 611 Akure, Ondo State, Nigeria 5Department of Materials and Metallurgical Engineering, Obafemi Awolowo University, Ile Ife, Nigeria *Corresponding author: [email protected] Received: January 09, 2020 Accepted: February 24, 2020 Abstract: This study was carried out to develop a green, simple and cost-effective route for synthesis of sodium cyanidevia aquohydrolysis of linamarin a cyanogenic glucoside found in cassava (Manihot esculenta Crantz). Two procedures were employed and compared, the acid hydrolysis method and direct (aquo) hydrolysis. The CN– ion released was reacted with Na+ via ion exchange to replace the hydroxyl ion (OH–) and yielded NaCN. The NaCN was crystallized via evaporation in an air ventilated oven by maintaining the temperature of the reaction solution at 100oC. The crystalized salt was quantified using the modified Vogel’s Argentometric method of cyanide quantification. The concentrations were found to be 10.56 mg/g for whole tuber, 13.92 mg/g for tuber tissue and 4.5 mg/g for cassava peels. Analyte grade sodium cyanide purchased off shelf was used as a reference. The crystals were characterized using, X-ray diffraction analysis; the X-ray diffractogram confirmed the products from acid hydrolysis was a cyanogen (CN2CN2) while the product from direct hydrolysis was sodium cyanide. -
4.3 Synthetic Graphite
BRNO UNIVERSITY OF TECHNOLOGY VYSOKÉ UČENÍ TECHNICKÉ V BRNĚ FACULTY OF ELECTRICAL ENGINEERING AND COMMUNICATION FAKULTA ELEKTROTECHNIKY A KOMUNIKAČNÍCH TECHNOLOGIÍ DEPARTMENT OF ELECTRICAL AND ELECTRONIC TECHNOLOGY ÚSTAV ELEKTROTECHNOLOGIE THE EFFECT OF ELECTRODE BINDERS TO ELECTROCHEMICAL PROPERTIES OF NEGATIVE ELECTRODE MATERIALS BACHELOR'S THESIS VLIV POJIV NA ELEKTROCHEMICKÉ VLASTNOSTI ZÁPORNÝCH ELEKTRODOVÝCH HMOT BAKALÁŘSKÁ PRÁCE AUTHOR András Zsigmond AUTOR PRÁCE SUPERVISOR Ing. Jiří Libich, Ph.D. VEDOUCÍ PRÁCE BRNO 2016 BRNO UNIVERSITY OF TECHNOLOGY Faculty of Electrical Engineering and Communication Department of Electrical and Electronic Technology Bachelor thesis Bachelor's study field Microelectronics and Technology Student: András Zsigmond ID: 154915 Year of study: 3 Academic year: 2015/16 TITLE OF THESIS: The Effect of Electrode Binders to Electrochemical Properties of Negative Electrode Materials INSTRUCTION: Get acquaint with Lithium-Ion batteries and their charactericti electrochemicla properties. Study operation principle of Litihum-Ion battery along with intercalaction process. Lead experiments which involve different kinds of binders and their using in electrodes. REFERENCE: Podle pokynů vedoucího práce. Assigment deadline: 8. 2. 2016 Submission deadline: 2. 6. 2016 Head of thesis: Ing. Jiří Libich, Ph.D. Consultant: doc. Ing. Jiří Háze, Ph.D. Subject Council chairman WARNING: The author of this bachelor thesis claims that by creating this thesis he/she did not infringe the rights of third persons and the personal and/or property rights of third persons were not subjected to derogatory treatment. The author isfully aware of the legal consequences of an infringement of provisions asper Section 11 and following of Act No 121/2000 Coll. on copyright and rights related to copyright and on amendments to some other laws (the Copyright Act) in the wording of subsequent directives including the possible criminal consequences asresulting from provisions of Part 2, Chapter VI, Article 4 of Criminal Code 40/2009 Coll. -
Iron Recovery from Bauxite Tailings Red Mud by Thermal Reduction with Blast Furnace Sludge
applied sciences Article Iron Recovery from Bauxite Tailings Red Mud by Thermal Reduction with Blast Furnace Sludge Davide Mombelli * , Silvia Barella , Andrea Gruttadauria and Carlo Mapelli Dipartimento di Meccanica, Politecnico di Milano, via La Masa 1, Milano 20156, Italy; [email protected] (S.B.); [email protected] (A.G.); [email protected] (C.M.) * Correspondence: [email protected]; Tel.: +39-02-2399-8660 Received: 26 September 2019; Accepted: 9 November 2019; Published: 15 November 2019 Abstract: More than 100 million tons of red mud were produced annually in the world over the short time range from 2011 to 2018. Red mud represents one of the metallurgical by-products more difficult to dispose of due to the high alkalinity (pH 10–13) and storage techniques issues. Up to now, economically viable commercial processes for the recovery and the reuse of these waste were not available. Due to the high content of iron oxide (30–60% wt.) red mud ranks as a potential raw material for the production of iron through a direct route. In this work, a novel process at the laboratory scale to produce iron sponge ( 1300 C) or cast iron (> 1300 C) using blast furnace ≤ ◦ ◦ sludge as a reducing agent is presented. Red mud-reducing agent mixes were reduced in a muffle furnace at 1200, 1300, and 1500 ◦C for 15 min. Pure graphite and blast furnace sludges were used as reducing agents with different equivalent carbon concentrations. The results confirmed the blast furnace sludge as a suitable reducing agent to recover the iron fraction contained in the red mud. -
PRODUCTION and REFINING of METALS (Electrolytic C25); PRETREATMENT of RAW MATERIALS
C22B PRODUCTION AND REFINING OF METALS (electrolytic C25); PRETREATMENT OF RAW MATERIALS Definition statement This subclass/group covers: Metallurgical or chemical processes for producing or recovering metals from metal compounds, ores, waste or scrap metal and for refining metal. Included in this subclass are processes drawn to: the production of metal by smelting, roasting or furnace method; the extraction of metal compounds from ore and concentrates by wet processes; electrochemical treatment of ores and metallurgical products for obtaining metals or alloys; apparatus thereof; preliminary treatment of ores, concentrates and scrap; general process for refining or remelting metals; apparatus for electroslag or arc remelting of metals; obtaining specific metals; consolidating metalliferous charges or treating agents that are subsequently used in other processes of this subclass, by agglomerating, compacting, indurating or sintering. Relationship between large subject matter areas This subclass covers the treatment, e.g. decarburization, of metallferrous material for purposes of refining. C21C, C21D and C22F provide decarburization of metal for modifying the physical structure of ferrous and nonferrous metals or alloys, respectively. C22B also possesses groups for obtaining metals including obtaining metals by chemical processes, and obtaining metal compounds by metallurgical processes. Thus, for example, group C22B 11/00 covers the production of silver by reduction of ammoniacal silver oxide in solution, and group C22B 25/00 covers the -
Iron-Rich Bauxite and Bayer Red Muds Yingyi Zhang, Yuanhong Qi and Jiaxin Li
Chapter Aluminum Mineral Processing and Metallurgy: Iron-Rich Bauxite and Bayer Red Muds Yingyi Zhang, Yuanhong Qi and Jiaxin Li Abstract Bauxite is the main source for alumina production. With the rapid development of iron and steel industry and aluminum industry, high-quality iron ore and bauxite resources become increasingly tense. However, a lot of iron-rich bauxite and Bayer red mud resources have not been timely and effectively recycled, resulting in serious problems of environmental pollution and wastage of resources. The com- prehensive utilization of iron-rich bauxite and red mud is still a worldwide problem. The industrial stockpiling is not a fundamental way to solve the problems of iron- rich bauxite and red mud. As to the recovery of valuable metals from iron-rich bauxite and red mud, there are a lot of technical and cost problems, which are serious impediments to industrial development. Applying red mud as construction materials like cement, soil ameliorant applications face the problem of Na, Cr, As leaching into the environment. However, the high-temperature reduction, smelting and alkaline leaching process is a feasible method to recover iron and alumina from iron-rich bauxite and red mud. This chapter intends to provide the reader an overview on comprehensive utilization technology of the low-grade iron-rich bauxite and Bayer red mud sources. Keywords: bauxite, iron-rich bauxite, Bayer red mud, Bayer process, magnetic separation, reduction and smelting process 1. Introduction With 8.30%, aluminum is the third element in the earth’s crust after the oxygen and the silicon, and for that reason, aluminum minerals are abundant with more than 250 kinds. -
Exploitation Strategic Plan and Business Model - Final
Exploitation strategic plan and business model - final Deliverable 8.4 © Copyright 2019 The INTMET Consortium Project Funded by the European Commission under the Horizon 2020 Framework Programme. Grant Agreement No 689515 EXPLOITATION PLAN-FINAL D8.4 PROGRAMME H2020 – Environment and Resources GRANT AGREEMENT NUMBER 689515 PROJECT ACRONYM INTMET DOCUMENT Deliverable 8.4 TYPE (DISTRIBUTION LEVEL) ☒ Public ☐ Confidential ☐ Restricted DUE DELIVERY DATE M36 DATE OF DELIVERY January 31 2019 STATUS AND VERSION NUMBER OF PAGES WP / TASK RELATED WP 8, task 8.4, 8.5 WP / TASK RESPONSIBLE MinPol AUTHOR (S) Prof. Dr. Horst Hejny, Dr. Angelika Brechelmacher, Prof. Dr. Günter Tiess PARTNER(S) CONTRIBUTING FILE NAME Exploitation strategic plan and business model - final DOCUMENT HISTORY VERS ISSUE DATE CONTENT AND CHANGES 1.0 30/01/2019 First Revision 1.1 31/01/2019 Small corrections ClC final 31/01/2019 for submission DOCUMENT APPROVERS PARTNER APPROVER CLC Francisco Sánchez 2 | 34 EXPLOITATION PLAN-FINAL D8.4 TABLE OF CONTENTS 1. PURPOSE ............................................................................................................................................................................................... 6 2. BUSINESS MODEL .................................................................................................................................................................................. 7 2.1 BASIC IDEA ............................................................................................................................................................................................... -
Notes Electrochemistry FG Vylechmann, Ph.D
N O T E S E L E C T R OC H E M I S T R Y . l E HMANN PH . D . F . G v C , y N EW YORK ’ MCGRAW PUBLI SHIN G COMPAN Y 1 906 CHA LE R S H. SEN FF A TO KEN OF EST EEM AN D REGARD P R E F A C E . T HE principal aim kept in view in the preparation o f these notes has been the giving o f a clear and con cise presentation o f the general prin ciples which un derlie electro chemical science . Endeavor has been made to meet the needs of students entering upon the study o f electro chemistry an d o f chemists interested in the application of electrical energy to chemical problems . The literature o f electro chemistry counts as its o wn a ' number of standard works which treat in detail the theories of the scien ce , the methods of electro chemical analysis , and D f e . the applications of el ctro chemistry i fering from these , the present notes aim merely to offer a general survey of the subject , to serve as an introduction to its study and to aid in the securing of a proper understanding and appreciation u of the work along individ al lines . ha s In the chapter on ele ctrote chnolo gy , spe cial endeavor bee n made to secure the most recent and reliable data and full advantage has been taken o f the information given in leading techni cal journals and in the excellent monographs o f s : E m Wasseri er Lo u Foer ter lektro che ie g s ngen , and of : E Wright lectri c Furnaces and their Industrial Applications . -
Extraction of Aluminium from Coal Fly Ash Using a Two-Step Acid Leach Process
EXTRACTION OF ALUMINIUM FROM COAL FLY ASH USING A TWO-STEP ACID LEACH PROCESS Alan Shemi A dissertation submitted to the faculty of Engineering and the Built Environment, University of Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Science in Engineering Extraction of Aluminium from CFA Alan Shemi DECLARATION I declare that this dissertation is my own unaided work. It is being submitted to the degree of Master of Science in Engineering to the University of the Witwatersrand, Johannesburg. It has not been submitted before for any other degree or examination in any other University. ---------------------------------- Alan Shemi 14th Day of May 2013 Page ii Extraction of Aluminium from CFA Alan Shemi ABSTRACT Hydrometallurgical extraction technologies provide a process route for resource recovery of valuable metals from both primary as well as secondary resources. In this study, the possibility of treating coal fly ash (CFA), a residue formed as a result of coal combustion in coal-fired power plants, was investigated. Eskom CFA contains significant amounts of alumina typically, 26-31%, in two dissimilar phases, namely amorphous and crystalline mullite, which may be processed separately. Due to its high silica content, however, CFA cannot be treated through the Bayer process route. Therefore, a leach-sinter-leach process was formulated that employed a two-step acid leach technique to extract alumina from CFA using sulphuric acid. In the preliminary test work, the effect of parameters on CFA leaching characteristics was investigated. From the experimental results, appropriate factor levels were found to be 6M acid concentration, 6 hours leaching time, 75°C temperature and 1:4 solid to liquid ratio. -
Recovery of Desilication Product in Alumina Industry
Recovery of Desilication Product in Alumina Industry Hasitha Indrajith de Silva B.Sc. Engineering (Honours) A thesis submitted for the degree of Doctor of Philosophy at The University of Queensland in 2013 School of Chemical Engineering Abstract Bayer process is used for the production of alumina from bauxite which contains siliceous minerals known as reactive silica. Reactive silica is also digested during the Bayer process, forming desilication product (DSP) which traps significant amount of sodium from the caustic soda used. DSP containing red mud is discarded to the bauxite residue storage areas causing alarming economic and environmental concerns to the alumina industry. Separation of DSP from red mud is a critical step to subsequent sodium recovery. Therefore, methods of separating DSP from red mud originated in a Western Australian alumina refinery were investigated in the present study. Red mud classified into five size classes was characterised using particle size measurement, material density, X-ray diffraction, X-ray photon spectroscopy, electron microscopy fitted with energy dispersive spectroscopy. Size separation alone resulted in an increase of DSP from ~7% to 12-14% in finer size classes of red mud. Since red mud contains more than 50% iron oxides, dissolution of these oxides would invariably result in an increase of DSP, therefore, several dissolution mechanisms of these oxides were investigated. Sodium Citrate-Bicarbonate-Dithionite (CBD) method resulted in an increase of DSP content from ~12 to 22%, while a comparative study was also carried out using deferroxiamine B (DFO-B) as the complexing agent. The use of ultrasonically assisted-CBD resulted in a significant improvement of iron dissolution from red mud. -
Electrolytic Reduction Hydrometallurgy
Metallurgy ,2nd Part C9 ,4th Sem Dr Sukla Chakladar Associate Professor,RNKWC,Midnapopre Electrolytic reduction For more reactive metals like Na,Mg ,Al etc cannot be reduce by carbon reduction process. So they can be reduced by electrolysis and these metals are not obtained by electrolysis from aqueous solution of their salt. So in these cases electrolytes are molten salts. Some e.gs Metal Electrolyte Reaction at the electrodes Na NaOH (Castner’s Process) At Cathode Na++e Na At anode 4OH- 2H2O+O2+4e NaCl(Down’s Process) Na++e Na(at Cathode) - 2Cl Cl2+2e(at Anode) Mg Molten MgO Mg2+ +2e Mg(Cathode) 2- O 1/2O2+e(Anode) 2+ MgCl2 Mg +2e Mg(Cathode) - 2Cl Cl2+2e(Anode) 3+ 2- Al Alumina(Al2O3,Na3AlF6+CaF2) Al2O3 2Al +3O Al3++3e Al(Cathode) 2- - 3O 3/2O2+3e (Anode) Hydrometallurgy Hydrometallurgy involves extraction of metal from ore by preparing an aqueous solution of a salt of the metal and recovering the metal from the solution. The operations usually involved are leaching, or dissolution of the metal or metal compound in water, commonly with additional agents; separation of the waste and purification of the leach solution; and the precipitation of the metal or one of its pure compounds from the leach solution by chemical or electrolytic means. It involves extraction of less electropositive or less reactive metals like gold and silver. Powdered ore is first dissolved in a suitable reagent by complex formation e.g. Ag2S+4NaCN 2Na[Ag(CN)2]+Na2S 4Au+8NaCN+2H2O+O2 4Na[Au(CN)2]+4NaOH Now a strong electropositive metal added to above salt solution from which metal is obtained. -
Tackling Key Engineering Challenges in Liquid Metal Batteries
Tackling Key Engineering Challenges in Liquid Metal Batteries: Temperature and Mass Transport by Rakan F. Ashour Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Supervised by Professor Douglas H. Kelley Materials Science Program Arts, Sciences and Engineering Edmund A. Hajim School of Engineering and Applied Sciences University of Rochester Rochester, NY 2019 ii Dedication To my daughter Ayah Ashour iii Table of Contents Biographical Sketch vi Acknowledgments vii Abstract viii Contributors and Funding Sources x List of Tables xi List of Figures xii Chapter 1: Introduction 1 1.1 Grid scale energy storage 1 1.2 Electrochemical energy storage 5 1.2.1 Electrochemistry notations and terms 5 1.2.2 Overview of existing technologies 6 Lead-Acid batteries 6 Lithium ion batteries 7 Sodium-Sulfur batteries 8 1.3 The liquid metal battery 9 1.4 Objectives 12 1.4.1 Reducing operating temperature 12 1.4.2 Understanding transport phenomena across scales 13 iv 1.4.3 Linking electrochemistry and magnetohydrodynamics 14 Chapter 2: Low Temperature Sodium Based Liquid Metal Batteries. 16 2.1 Review of Thermodynamics. 16 2.1.1 From the first law to battery voltage. 16 2.2 Previous work on sodium based liquid metal batteries. 21 2.3 Experimental methods 23 2.3.1 Salt Preparation 23 2.3.2 Electrode Preparation 26 2.4 Results and Discussion 26 2.4.1 The Binary NaOH,NaI system 26 2.4.1 The Ternary NaNH2,NaOH,NaI system 30 2.5 Summary 45 Chapter 3: Fluid Dynamics of Liquid Metal Batteries 48 3.1 MHD of liquid metal batteries 48 3.2 Governing Equations 52 3.2.1 Thermal Convection: The Rayleigh- Bénard Instability 53 3.2.2 Electromagnetically Driven Flows 55 3.2.3 Flows Driven by Electromagnetic and Buoyant Forces 58 3.3 Experimental Methods 59 3.4 Results & Discussion 61 3.5 Summary & Engineering Implications 72 Chapter 4: Linking Electrochemistry and Fluid Dynamics 75 v 4.1 Kinetics of mass transport in liquid metal batteries.