Acid-leaching mechanism of electroplating sludge: based …
Acid leaching is the most common method to extract valuable heavy metals for resource recycling and environmental protection. However, the coexisting elements, which are released from electroplating sludge to the leaching solution, will hinder the recycling of valuable heavy metals. In this work, dynamic acid-leaching experiments, X …
Thorough extraction of lithium and rubidium from
The alkaline leaching method has the disadvantages of a larger consumption of reagents and lower economic benefits. The extraction rate of lithium in the sulfuric acid method is relatively poor, and the addition of a large amount of fluorine increases the difficulty of subsequent processing. The higher extraction rate of lithium …
Carbon-silica mesoporous composite in situ prepared …
When the acid concentrations exceed 20 wt% or the reaction time closes to 240 min, the leaching rates reach to a saturation value. This is because, with the increasing of reaction temperature, the thermal motion rate of molecules in the solution increases and the increasing HCl concentration is expected to provide more H + in the solution thus ...
Mechanisms underlying the acid leaching process for …
The results of leaching with an eco-friendly organic acid are also presented, along with comparative leaching experiments with other positive electrode materials. …
Selective extraction of uranium from uranium–beryllium ore by acid leaching
Effect of H 2 SO 4 concentration. Sulfuric acid, as the leaching agent, is a key factor influencing the leaching efficiency of U. The effect of H 2 SO 4 concentration on U leaching was demonstrated in Fig. 1, with the other conditions fixed at: the leaching temperature of 348.5 K, the liquid–solid ratio of 4:1 and the leaching time of 50 min.The …
Synergistic Approach for Selective Leaching and …
A novel method that employs org. acid recovery using citric acid and salicylic acid was used to enhance the leaching of metal ions from the cathode …
Elimination of Lithium from Aluminium Electrolyte by Acid Leaching Method
This paper report on an acid leaching method to eliminate lithium from aluminium electrolyte system (CR=3). Both deionized water and HNO 3 were used. Also, the effects of the influences of acid concentration, leaching time, liquid-to-solid (L/S) ratio and temperature on the leaching efficiency were investigated.
Acid-leaching mechanism of electroplating sludge: …
Acid leaching is the most common method to extract valuable heavy metals for resource recycling and environmental protection. However, the coexisting elements, …
The Use of Acid Leaching to Recover Metals from …
Acid leaching (25 g material, 250 mL HCl, room temperature, 50 days) explored pH, temperature, and particle size. Lower pH (pH < 3) led to greater metal …
Separation and recovery of valuable elements from acid …
In our previous work, we focused on the direct treatment of SCC based on the hydrothermal acid-leaching method and found that the carbon content of the treated SCC could be increased to about 98 % by a simple one-step acid leaching [20]. However, the existing process is difficult to realize the separation and recovery of all elements in the ...
Hydrometallurgical Processing of a Manganese Concentrate by Acid
Another method for hydrometallurgical extraction is acid digestion–leaching. Acid digestion is a process in which an ore/concentrate is mixed with a concentrated acid solution and heated to temperatures below the boiling point of the solution [].Through the acid digestion process, the mineral network is destroyed, and its …
Acetic acid leaching of neodymium magnets and …
open access. •. An environmentally friendly acetic acid leaching process for NdFeB magnets. •. Main effects and interactions of key factors illuminated - flexible …
A novel and efficient method combining acid leaching and …
The aim of this work is the purification of MG-silicon powder using a method combining acid leaching and thermal annealing. It describes experiment carried out by using a tungsten lamps furnace (rapid thermal processing, RTP) to purify silicon powder under controlled atmosphere. This process enables to segregate the impurities to the surface of ...
Fuels | Free Full-Text | A Critical Review of Extraction Methods …
Such leaching methods could recover over 90% of vanadium from the petcoke ash, but it is limited to certain compositions. 4FeV 2 O 4 + O 2 (g) = 2Fe 2 O 3 + 4V 2 O 3 (ΔG 850 °C = −181 kJ) (7) ... Acid leaching is the process of recovering elements from a feedstock by solubilizing them in an acid. The desired elements could be …
Leaching of Metals from e-Waste: From Its Thermodynamic …
Thiourea acid leaching process, performed on the solid filtrate obtained after three oxidative leaching steps, was carried out with 20 g/L of CS(NH2)2, 6 g/L of Fe3+, 0.5 M H2SO4, The cross-leaching method was applied by reusing of thiourea liq. suspension and immersing 5 g/L of this reagent for each other expt. material of leaching.
Scandium Recovery Methods from Mining, Metallurgical …
Due to the suitable leaching efficiency of scandium, it is believed that direct acid leaching with dilute nitric acid is acceptable for RM with a low iron oxide content (less than 30 wt%) . Recently Boyarintsev et al. [ 142 ] evaluated the leaching of scandium from the Russian RM using 2.0 mol/L Na 2 CO 3 under carbonation conditions (CO 2 gas ...
Insight into leaching rare earth from ion-adsorption type …
To ensure a stable leaching process, the soaking leaching method was used in this experiment to promote the leaching reaction to reach thermodynamic equilibrium within a certain period. Therefore, the leaching capacity of the citric acid leaching system could be determined from the perspective of thermodynamic …
Selective and efficient extraction of lithium from
Chen et al. had delved into a pressurized leaching method utilizing Na 2 CO 3 (Chen et al., ... Therefore, nitric acid leaching at atmospheric pressure is not an effective method for lithium extraction. Download : Download high-res image (287KB) Download : Download full-size image; Fig. 4. Comparison of extraction of α-spodumene and β …
Dealkalization and Leaching Behavior of Fe, Al, Ca, and Si of …
Dealkalization is the necessary step for the multipurpose use of red mud (RM), and acid leaching is a productive method to realize the dealkalization of RM. Most researches focus on recovering metals from the highly alkaline waste by pure acid leaching or stabilization by dealkalization. In this study, according to the strong alkalinity of RM …
High efficiency purification of natural flake graphite by …
The alkali-melting acid leaching purification method is used to further purify the PG1 to obtain the PG3 with the fixed carbon content of 99.93%. The fixed carbon content is increased by 93.7% through flotation combined with alkali solution and acid leaching. The purification process of GO is systematically evaluated and analyzed by …
Selective leaching of lithium from spent lithium-ion …
Traditional hydrometallurgical methods for recovering spent lithium-ion batteries (LIBs) involve acid leaching to simultaneously extract all valuable metals into the …
Metallurgy
Metallurgy - Leaching, Extraction, Refining: Oxides are leached with a sulfuric acid or sodium carbonate solvent, while sulfates can be leached with water or sulfuric acid. Ammonium hydroxide is used for native ores, carbonates, and sulfides, and sodium hydroxide is used for oxides. Cyanide solutions are a solvent for the precious metals, …
Direct Electrochemical Leaching Method for High …
However, chemical leaching relying on the additional acid seriously threatens the global environment and nonselective leaching also leads to low Li recovery purity. Here, we first reported a direct electro …
Acid leaching | industrial process | Britannica
Other articles where acid leaching is discussed: uranium processing: Leaching: Acid leaching is commonly performed by agitating an ore-leach mixture for 4 to as long as 48 hours at ambient temperature. Except in special circumstances, sulfuric acid is the leachant used; it is supplied in amounts sufficient to obtain a final leach liquor at about…
A closed-circuit cycle process for recovery of carbon and …
In this work, hydrothermal acid-leaching method was used for the recovery of carbon and valuable components in SCC. Through the characterization of raw materials and thermodynamic calculation, the existence forms of various impurities in SCC were clarified, and their reaction characteristics in acid were revealed.
An effective method for directly extracting lithium
In this study, a novel lithium extraction method was proposed for α-spodumene by combining activated roasting and sulfuric acid leaching. First, the thermodynamics of the roasting process demonstrated that α -spodumene was converted into β -spodumene, which reacted with CaO to produce acid-soluble LiAlSiO 4 and …
A clean method of precipitation vanadium from the …
For this reason, a clean method to extract vanadium from the Fe 3− x V x O 4 minerals by single step leaching was proposed in our previous study (Yan et al., 2018, Chen et al., 2020a).In this method, vanadium could be directly leached by oxalic acid synergized with Fe powder under hydrothermal conditions.
An efficient method combining thermal annealing and acid leaching …
Following rapid thermal processing (RTP), silica is subjected to an acid leaching using an acid mixture solution (AS2) composed of HF (5%):HCl (4%) with a volume fraction of 1:7. During this acid leaching, which was carried out under power ultrasound, an excess of the obtained silica was abundantly dissolved in 10 ml of (AS2) …
ELIMINATION OF LITHIUM FROM ALUMINIUM …
This paper used an acid leaching method as LiF reacts easier with acid than Li2NaAlF6. A one- step acid leaching method to remove LiF from an electrolyte with CR of 3.0 was used. The effects of the acid concentration, leaching time, liquid-to-solid (L/S) ratio and temperature on the leaching efficiency were investigated. Experimental
Response Surface Method Optimization of Mixed Acid …
The RSM results indicate that the optimum values for those parameters are as follows: temperature 72 ℃, sulfuric acid concentration 1.48 mol/L, oxalic acid concentration 0.96 mol/L, and reaction time 2 h. Under the optimal leaching conditions, the model predicts a maximum leaching yield of 99.5%, compared to the value of 99.1% obtained ...