Mohammad Bagher FathiBahram RezaiEskandar Keshavarz Alamdari
6页
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0040" view="all">In this study adsorption of rhenium ions from single and bi-component solutions (Re-Mo) by Purolite A170 was studied experimentally and described by isotherm, kinetic and thermodynamic modeling. Considering coefficient of determination (R<ce:sup loc="post">2</ce:sup>) and values of root mean squared error (RMSE) for the multicomponent isotherms, the extended model of Freundlich isotherm was found to be successful. Moreover, fitting the time-dependent data into different mechanisms showed that the data comply well with the pseudo-second order model. Results from the binary systems demonstrated that the presence of the secondary metal ions in the system causes a decrease in the adsorption capacity of rhenium, which is mainly due to the competitive effects of metals for adsorption sites. Furthermore, evaluation of thermodynamic parameters showed that the reaction mechanisms are different for both systems; however, due to negative values of ΔH, in competitive condition the adsorption of rhenium becomes more feasible with increasing the temperature.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0045" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">Uptake of perrhenate ions from single and binary (Re-Mo) systems was studied.</ce:para></ce:list-item><ce:list-item id="li1005"><ce:label>?</ce:label><ce:para id="p1005" view="all">The results were analyzed using equilibrium isotherms, kinetics and thermodynamic modeling.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Extended Freundlich isotherm model was well fitted to binary adsorption data.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">Presence of competing ions adversely impacts on the process.</ce:para></ce:list-item><ce:list-item id="li0020"><ce:label>?</ce:label><ce:para id="p0020" view="all">Kinetics were controlled by the pseudo-second-order rate equation.</ce:para></ce:list-item><ce:list-item id="li0025"><ce:label>?</ce:label><ce:para id="p0025" view="all">Competitive sorption process of perrhenate ions was found exothermic and spontaneous.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
Simon P.W. HagemanRenata D. van der WeijdenAlfons J.M. StamsCees J.N. Buisman...
9页
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0050" view="all">Biological reduction of soluble selenate to insoluble elemental selenium enables the removal and recovery of selenium from aqueous streams. Economic, efficient biological selenium recovery depends on properties of selenium particles such as size, density, stability, hydrophilic character and attachment to the biomass. In batch and fed-batch reactors using anaerobic sludge, the influence of pH (6-9) and temperature (20–50°C) on the morphology, structure and stability of the biologically produced selenium particles were studied using SEM, XRD, and light microscopy. At a high pH or a high temperature these experiments resulted in grey crystalline hexagonal acicular selenium particles, while at a low pH combined with a low temperature red amorphous nanospheres were dominant. Particle stability tests were carried out by changing the temperature or pH after the particles had formed. Red amorphous selenium spheres (produced at pH=7 and 30°C) transformed gradually towards the grey hexagonal structure at 50°C over a period of three weeks, whereas the transformation was less or not detected under other process conditions (according XRD). We show here that biological selenium particle crystallinity, shape and color can be controlled by temperature and pH. However, the choice for the temperature and pH in the bioreactor should not limit the biomass' reduction capacity of selenate. The production of crystalline particles is an important first step to grow larger selenium particles in the future in order to reduce costs for selenium recovery in bioreactors.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="graphical" xml:lang="en" view="all"><ce:section-title id="st0010">Graphical abstract</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para>Display Omitted</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0015" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0015">Highlights</ce:section-title><ce:abstract-sec id="as0015" view="all"><ce:simple-para id="sp0060" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">Temperature and pH control the crystallinity of produced biological Se particles.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Crystalline selenium particles are acicular and amorphous particles are spherical.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">Once Se particles are produced, pH and temperature control is less effective.</ce:para></ce:list-item><ce:list-item id="li0020"><ce:label>?</ce:label><ce:para id="p0020" view="all">Crystalline Se is bigger and less attached to the biomass compared to amorphous Se.</ce:para></ce:list-item><ce:list-item id="li0025"><ce:label>?</ce:label><ce:para id="p0025" view="all">Crystalline Se production is the first step to grow larger Se particles for recovery</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0055" view="all">The particle settling is a basic phenomenon: however, it determines the design of many unit operations and machines of mineral processing. A new test device has been developed in order to measure the terminal settling velocity of large steel balls settling in fine particulate solids - water mixtures. The developed inductive sensor does not influence the motion of the ball and it can be applied for non-transparent and non-Newtonian fine suspensions. A new hypothesis, namely a continuity theory for coarse disperse systems is introduced here. According to this theory, if the particles of a fine suspension are so small that they fit into the laminar sub-layer around a settling coarse particle, the fine suspension can be treated as a continuum. If they do not fit, hindered settling dominates between the coarse and fine particles. It was also recognised that if a particle settles at a constant speed in any media that is in an equilibrium state, therefore, the “equilibrium mean surficial shear stress (τ<ce:inf loc="post">e</ce:inf>)” and the “equilibrium mean surficial shear rate” have been introduced. The equilibrium mean surficial shear stress can be calculated initially, because it is simply the force of gravity minus the buoyant force over three times the total surface of the particle. Once τ<ce:inf loc="post">e</ce:inf>is known, the equivalent Newtonian absolute viscosity can be determined and the terminal settling velocity of particles falling in non-Newtonian media can be calculated by the known procedures for Newtonian fluids.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0060" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">A new settling test instrument was developed with inductive sensor.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Settling velocity of balls in non-transparent, non-Newtonian real suspensions can be measured.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">If a particle is settling down with constant speed in any media that is an equilibrium state</ce:para></ce:list-item><ce:list-item id="li0020"><ce:label>?</ce:label><ce:para id="p0020" view="all">A universal terminal settling velocity calculation in non-Newtonian suspensions is presented.</ce:para></ce:list-item><ce:list-item id="li0025"><ce:label>?</ce:label><ce:para id="p0025" view="all">The introduced continuity theory helps understanding ball milling media behaviour.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0055" view="all">The main purpose of this study is to investigate the effect of reaction temperature and NH<ce:inf loc="post">4</ce:inf>HCO<ce:inf loc="post">3</ce:inf>on the overall performance of a pH swing mineral carbonation. The overall performance of the pH swing process is investigated in terms of carbonation efficiency and product purity. Initially, 2M H<ce:inf loc="post">2</ce:inf>SO<ce:inf loc="post">4</ce:inf>is used for red gypsum dissolution at 70°C. Then in the second stage, NH<ce:inf loc="post">4</ce:inf>OH is added for increasing the solution pH and removing the impurities from solutions. Finally, CO<ce:inf loc="post">3</ce:inf><ce:sup loc="post">2–</ce:sup>is introduced to calcium rich solution in the form of pure CO<ce:inf loc="post">2</ce:inf>and NH<ce:inf loc="post">4</ce:inf>HCO<ce:inf loc="post">3</ce:inf>. The experimental results show that using NH<ce:inf loc="post">4</ce:inf>HCO<ce:inf loc="post">3</ce:inf>improves carbonation efficiency and product purity. Carbonation efficiency attains a maximum value at 75°C and then decreases gradually with increasing temperature up to 300°C, with both CO<ce:inf loc="post">2</ce:inf>and NH<ce:inf loc="post">4</ce:inf>HCO<ce:inf loc="post">3</ce:inf>. In this research, CaCO<ce:inf loc="post">3</ce:inf>with the maximum purity of 99.05% is produced successfully when NH<ce:inf loc="post">4</ce:inf>HCO<ce:inf loc="post">3</ce:inf>is used as a CO<ce:inf loc="post">3</ce:inf><ce:sup loc="post">2–</ce:sup>source.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0060" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">Red gypsum can be used as a raw material for mineral carbonation.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Carbonation efficiency of red gypsum attains maximum value at 75°C.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">High purity CaCO<ce:inf loc="post">3</ce:inf>(89.85–99.05%) is produced through pH swing process.</ce:para></ce:list-item><ce:list-item id="li0020"><ce:label>?</ce:label><ce:para id="p0020" view="all">Carbonation efficiency and CaCO<ce:inf loc="post">3</ce:inf>purity is higher with NH<ce:inf loc="post">4</ce:inf>HCO<ce:inf loc="post">3</ce:inf>rather than CO<ce:inf loc="post">2</ce:inf>.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0145" view="all">Quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN) and diagnostic leaching (DL) are the two main methods to evaluate the gold refractoriness nature. Limited availability of QEMSCAN or its cost sometimes can be the drive to use DL method, or vice versa.</ce:simple-para><ce:simple-para id="sp0150" view="all">We present the results of a comparative study that investigates and compares the origin of the refractoriness of two different gold samples with QEMSCAN and DL. As a baseline, the gold recovery values of samples 1 and 2 via the standard cyanidation process over a leaching period of 24h were 74% and 54%, respectively. Based on the DL tests, the refractoriness of samples 1 and 2 was mostly related to the fine dissemination and association of the electrum (Au-Ag alloy) and gold telluride with the sulfide minerals, particularly pyrite. The QEMSCAN analysis provided more details about the gold deportment in the two samples. The QEMSCAN results showed that the gold in the two samples was mostly present as electrum and gold-telluride. In sample 1, about 89% of the gold occurred in the form of electrum with a 63% Au and 36% Ag composition. The main gold form in sample 2 was gold-telluride (81%). Energy dispersive X-ray spectroscopy (EDS) results demonstrated that the gold telluride phase was in the form of calaverite (AuTe<ce:inf loc="post">2</ce:inf>) in both samples. The QEMSCAN results suggested that 77% of gold in sample 1 and 88% of gold in sample 2 were liberated or locked in the sulfide minerals, and the balance was the solid solution gold. Based on the QEMSCAN study, the total liberated gold and the gold locked in the sulfide minerals are expected to be amenable to cyanide leaching after a complete sulfide oxidation process, i.e. pretreatment. DL tests, however, suggested that 91% of the gold in sample 1 and 87% of the gold in sample 2 were leachable after the oxidation of sulfides in the two samples.</ce:simple-para><ce:simple-para id="sp0155" view="all">Lastly, the two samples were pretreated by (1) roasting, and (2) atmospheric oxidation to oxidize sulfide minerals and render the samples more amenable to cyanide leaching. The gold recoveries of the roasting calcines by cyanidation were 93% and 76% for samples 1 and 2, respectively. The cyanidation of the atmospheric oxidation residues provided a greater gold recovery for both sample 1 (96%) and sample 2 (85%). Gold recovery for sample 1 was underestimated by QEMSCAN, however the gold recovery values were estimated well by DL.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0160" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">Gold ore and gold concentrate refractoriness were compared with QEMSCAN and diagnostic leaching.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Gold was mainly encapsulated/associated with the sulfide-bearing minerals.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">The findings from DL was in concurrence with the data attained from QEMSCAN.</ce:para></ce:list-item><ce:list-item id="li0020"><ce:label>?</ce:label><ce:para id="p0020" view="all">Roasting and atmospheric leaching were employed to put in test the results of QEMSCAN and DL.</ce:para></ce:list-item></ce:list></ce
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0055" view="all">In this study, the effect of sodium chloride on the flotation of a fine coal sample was investigated. The results indicated that flotation of coal was highly dependent on changes in sodium chloride concentration. An increase in the sodium chloride concentration resulted in increases in the combustible recovery as well as concentrate ash content. The froth stability and particle size distribution in the slurries with different sodium chloride concentrations were measured. The results showed that the increase in froth stability and enlargement in particle size were both favorable for the recovery of coal particles in flotation. The underlying mechanism was investigated by examining the zeta potential of pure coal particles and pulp rheology. The pulp rheology measurements clearly indicated that changes in froth stability were attributed to changes in slurry viscosity, which ultimately enhanced the recovery of coal particles. The decrease in zeta potential was responsible for the increase in particle size in slurries due to particle coagulation, which is caused by a decrease in electrostatic repulsion among the particles.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0060" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">The addition of sodium chloride increased the combustible recovery significantly.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Slurry viscosity was measured to demonstrate the improvement of froth stability.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">Decrease of zeta potential can be responsible for the enlargement of particle size.</ce:para></ce:list-item><ce:list-item id="li0020"><ce:label>?</ce:label><ce:para id="p0020" view="all">Enlargement of particle size may enhance bubble-particle collision and attachment.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0055" view="all">This paper introduced dextran sulfate sodium, a medical intermediate rich in sulfate group, as a potential depressant for calcite and fluorite in scheelite flotation. The flotation behaviors of scheelite, calcite and fluorite under different pulp pH with dextran sulfate sodium acting as depressant and sodium oleate acting as collector were studied through micro-flotation tests. The results showed that when sodium oleate was used alone, the three minerals floated well and were difficult to separate. Dextran sulfate sodium exhibited a selective depressant effect on calcite and fluorite flotation when it was added before sodium oleate. Using dextran sulfate sodium as depressant could achieve the preferential flotation separation of scheelite from calcite and fluorite by control of pulp pH at 7.0. The selective depressant effect of dextran sulfate sodium on calcite and fluorite was explored through surface analyses including zeta potential measurements, contact angle measurements and FTIR studies on mineral samples treated with dextran sulfate sodium and/or sodium oleate. On the basis of the surface analyses, a selective adsorption model of dextran sulfate sodium on calcite and fluorite was proposed.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0060" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">Scheelite, calcite and fluorite float well using sodium oleate as collector.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Dextran sulfate sodium has a depressant effect on the flotation of calcite and fluorite.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">Dextran sulfate sodium can chemically adsorb on calcite and fluorite surface.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
Jonas Addai-MensahWilliam SkinnerGeorge Blankson Abaka-Wood
10页
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0130" view="all">Flotation, which exploits the differences in the surface wettability of minerals to effect separation, has been crucial in rare earth elements (REE) beneficiation. Monazite, a phosphate mineral commonly containing REE (typically lanthanum, cerium, and neodymium), occurs in association with hematite and quartz gangue minerals in some low grade deposits. In this study, the physicochemical properties including contact angle, zeta potential, and floatability of monazite, hematite, and quartz were determined in the presence of oleic acid as a collector. Contact angle measurements indicated adsorption of oleic acid onto the minerals' surfaces. Zeta potential measurements were used to elucidate oleic acid adsorption mechanism onto the mineral particle surfaces. Results from zeta potential measurements indicated that depressants are required to achieve selective flotation recovery of monazite from hematite and quartz. The flotation test results confirmed poor selectivity between monazite; and hematite and quartz, respectively. However, rare earth oxides (REO) in monazite floated better than both hematite and quartz at all the oleic acid dosages investigated. The use of sodium silicate and starch as depressants enhanced the selective flotation recovery of REO from hematite and quartz mixtures.</ce:simple-para></ce:abstract-sec></ce:abstract>]]>
F. Alvarez-MartinN. Moreno BermejoY. Luna GalianoC. Leiva...
9页
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0095" view="all">Copper is commonly produced by hydrometallurgical processes. The production of this metal results in the formation of emissions (unwanted solids, liquids and gases). In this paper, an effluent from a Cu producer company is valorized by means of Fe and Cu recovery.</ce:simple-para><ce:simple-para id="sp0100" view="all">In the current process, an effluent from the secondary solvent extraction (secondary raffinate) was sent to neutralization plant to be discharged. In this paper a modification of the process is proposed. The secondary raffinate was contacted with TP207 resin for Fe<ce:sup loc="post">3+</ce:sup>and Cu recovery. Metals were eluted from the resins using another real effluent (primary raffinate, effluent from the primary solvent extraction) from the same plant.</ce:simple-para><ce:simple-para id="sp0105" view="all">Experiments for the uptake and elution were carried out in batch and in columns. The effect of pH, resin dosing, and temperature onto metals retention are analyzed. Retention efficiencies (loading capacities) were 50.1% (8.1mg·g<ce:sup loc="post">?1</ce:sup>) for Cu and 54.8% (23.2mg·g<ce:sup loc="post">?1</ce:sup>) for Fe<ce:sup loc="post">3+</ce:sup>under the optimal operational conditions (pH=0.45 and<ce:italic>T</ce:italic>=65°C). These values were confirmed in column tests. It is possible to recover Fe<ce:sup loc="post">3+</ce:sup>and Cu from the secondary raffinate, leaving most of Fe<ce:sup loc="post">2+</ce:sup>and other elements in solution. The experimental affinities that TP207 showed are: Cu>Fe<ce:sup loc="post">3+</ce:sup>>Fe<ce:sup loc="post">2+</ce:sup>>Zn.</ce:simple-para><ce:simple-para id="sp0110" view="all">The elution of Fe and Cu was quantitatively achieved with concentrated H<ce:inf loc="post">2</ce:inf>SO<ce:inf loc="post">4</ce:inf>solution. When acidified primary raffinate was used as eluting solution, an enriched solution containing 14.3g Cu·L<ce:sup loc="post">?1</ce:sup>, 20.3g Fe<ce:sup loc="post">2+</ce:sup>·L<ce:sup loc="post">?1</ce:sup>, and 18.6 de g Fe<ce:sup loc="post">3+</ce:sup>·L<ce:sup loc="post">?1</ce:sup>was obtained. This enriched primary raffinate can be reintroduced in the process as leaching solution.</ce:simple-para><ce:simple-para id="sp0115" view="all">So, after the modification of the process, using secondary raffinate as loading solution and acidified primary raffinate as eluting solution, the ion-exchange stage could substitute the external FeSO<ce:inf loc="post">4</ce:inf>addition. In addition, 30–80kgCu·h<ce:sup loc="post">?1</ce:sup>are reintroduced in the process.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="graphical" xml:lang="en" view="all"><ce:section-title id="st0010">Graphical abstract</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para>Display Omitted</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0015" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0015">Highlights</ce:section-title><ce:abstract-sec id="as0015" view="all"><ce:simple-para id="sp0125" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">Copper hydrometallurgy plant</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Secondary raffinate valorization by ion-exchange</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">Enriched solution contai
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0045" view="all">The underground separation of gangue from coal is an important part of the process of reducing transportation costs and improving production efficiency. A new method is proposed in this paper to separate gangue from coal on the basis of density, calculated from volume using three-dimensional (3D) laser scanning technology. This approach is based on the laser triangulation method and weight. Taking into account the weigh-in-motion technology that is currently widely applied, the main objective of this approach is to determine the volume of the object being measured. Thus, the principles of 3D laser scanning and laser triangulation were studied in detail and a relative formula was deduced. The reasons and solutions for possible errors are also analyzed in this paper, depending on the method applied to measure volumes of gangue and coal. Physical relationships of objects to be measured, as well as laser and measuring data planes are also presented, depending on principles of 3D laser scanning. A parameter selection method is presented to determine the appropriate photoelectric recognition device to use for coal or gangue, while error due to voids between objects was measured, and transportation belts analyzed. The assumption put forward in this study is that the ratios of voids between objects, transportation belt, and the exact volume of objects all conform to a normal distribution; this was shown to be the case by both experiments and statistical theory. A mathematical model was therefore constructed that is suitable for the recognition of coal and gangue based on this theory, while algorithms of recognition threshold values and identification rate are presented.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0050" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">A method for distinguishing gangue from coal was presented, and a photoelectric identification system was designed.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">The statistical relationship between the volume of coal, gangue, and actual volume conforms to a normal distribution.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">A mathematical model for the identification of coal and gangue is established. A recognition threshold were calculated.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
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