47 results about "Lixiviant" patented technology

The invention provides a method for producing dehydrated calcium sulfate whisker, comprising: using copper, lead, zinc, aluminium, nickel, cobalt, stannum, non-ferrous metal secondary resource cycle utilizing, calcium nitrate solution produced in treating process of electroplating waste, calcium chloride solution, or mixed water solution of calcium nitrate and calcium chloride as raw material, using sulfuric acid as calcium ion precipitant, adding whisker shape regulating agent, controlling reaction condition, regenerating aqua fortis or hydrochloric acid lixiviant, and simultaneously producing ultralong and big length to diameter ratio calcium sulphate dihydrate whisker. After calcium sulphate dihydrate whisker is deposited from calcium nitrate solution, calcium chloride solution or the mixed solution of calcium nitrate and calcium chloride are deposited, the water solution is translated to be nitric acid solution, hydrochloric acid solution or a mixed solution of nitric acid and hydrochloric acid, returning back to leaching out or treating process for processing non-ferrous metal mineral substance, non-ferrous metal secondary resource or electroplating remove. The calcium sulphate dihydrate whisker is treated by microwave heating, forming calcium sulfate hemihydrate or anhydrous sulphate of calcium after dehydration.

Processes are provided for recovering precious metals from refractory materials using thiosulfate lixiviants. The processes can employ lixiviants that include at most only small amounts of copper and/or ammonia and operate at a relatively low pH, reduction of polythionates, inert atmospheres to control polythionate production, and electrolytic solutions which provide relatively high rates of precious metal recovery.

Precious metal recovery by thiosulfate leaching where thiosulfate lixiviant is generated in situ employing elemental sulfur generated from partial oxidation of sulfidic precious metal-bearing feed and/or employing reactants from processing effluent.

This invention is stable alkaline thiourea system and its selective dunking gold method. the materials are gold mine of low sulfur content, calcine or gold contain abatement. Cyanogens lixiviant is alkaline thiourea, stabilizer is sodium sulphite or sodium silicate, they constitute high stability alkaline thiourea system, and bland oxidizing agent is potassium ferricyanide with moderate electric potential during sunking process. Alkaline thiourea stability problem is solved radically, reagents used in this invention is nontoxic, gold dissolving is fast, the reaction only needs 3~4 hours, dunking gold rate is 80%. There is selectivity in gold dissolving, associated metal or basic metal as Fe, Co, Ni, Cu, Ag of waste gold matter is not easy corrode in alkaline condition. Gold recovery from dunking solution is convenient. There is almost no corruption to equipment comparing to acid solution, equipment design and run requirement is low.

The invention relates to modifications of a non-ammoniacal thiosulfate process of leaching precious metals (e.g. gold or silver) from precious metal-containing ores. The process involves leaching the ore with an aqueous lixiviant containing a soluble thiosulfate other than ammonium thiosulfate, a copper compound and an organic compound that serves as a copper ligand (i.e. a ligand-forming compound). Four modifications of this process are effective for increasing the amount of precious metal that can be extracted, reducing the consumption of materials, or for improving the rate of extraction. These four process, which may be used singly or in any combination, include (a) additions of soluble lead (e.g. as lead nitrate), (b) additions of thiourea, (c) increases in dissolved oxygen, and (d) increases of temperature at ambient pressure. This avoids the use environmentally harmful chemicals and allows for extraction from a variety of ores, e.g., containing substantial amounts of sulfides and/or quartz.

A hydrometallurgical process for the removal of arsenic and antimony from a so-called “dirty” copper concentrate (101) is described. The process comprises the following steps: Step 1: repulping (100) the “dirty” copper concentrate with an alkaline lixiviant (102, 103), and subjecting the “dirty” copper concentrate to an alkaline leaching process (“the Leach”) in a Leach reactor (110). The arsenic and antimony are dissolved in the Leach to produce a “clean” copper concentrate (138) and leach discharge liquor (132). Step 2: subjecting the Leach discharge liquor (132) to a lime treatment step (151) in order to regenerate (150) the alkaline lixiviant as well as precipitate an impurity rich precipitate (161) containing arsenic and antimony. Then the impurity rich precipitate (161) is separated (160) from the regenerated alkaline lixiviant (162). The impurity rich precipitate is washed and disposed of in an environmentally safe condition. Step 3: recycling the regenerated alkaline lixiviant (162) to the Leach in Step 1, and so employing the recycled alkaline lixiviant (102) in the further extraction of arsenic and antimony from incoming “dirty” copper concentrate (101).

The invention provides a process for the leaching of a laterite ore, concentrate, tailings or waste rock for the recovery of value metals, at least one value metal being nickel. The laterite ore or concentrate is subjected to a leaching step with a lixiviant comprising hydrochloric acid to leach nickel from the laterite ore, followed by a liquid/solids separation step. The liquid obtained is subject to solvent extraction with a dialkyl ketone, to obtain a solution rich in iron and a raffinate. Separation of iron from cobalt and nickel is obtained.

The invention discloses a method for reducing and lixiviating zinc containing material by sulfur dioxide. The method comprises the following steps: adding the zinc containing material into an acid lixiviant to lixiviate the zinc containing material by the acid lixiviant; in the process of lixiviating, introducing sulfur dioxide through the mixture of the acid lixiviant and the zinc containing material to realize reduction and lixiviation by sulfur dioxide. The method in the embodiment of the invention achieves the advantages of high zinc and ferrum lixiviation rate, low slag rate and high adaptability to raw materials, i.e. the method is suitable for processing various zinc containing materials; the method can reduce the possibility that organics and foreign ions enter the system, achieves the advantages of no elemental sulfur and high lead/silver enrichment degree, also can optimize the subsequent technical flow and reduce equipment investment and energy consumption.

The invention relates to a grinding and leaching pretreatment process of refractory gold ore. The process is mainly used for combined pretreatment of anaerobic roasting and mechanical activated leaching on the refractory gold ore. The process specifically comprises the following steps that S1, the gold ore is broken, and subjected to ball milling and powdering, and gold ore powder is obtained; S2,the obtained gold ore powder is placed in gas atmosphere without oxygen or vacuum to be roasted, and after roasting, roasting slag and smoke are obtained; S3, the roasting slag is subjected to grinding and pulp mixing, slurry is placed in a reaction kettle to be subjected to temperature control and stirring leaching, and a base metal leaching agent and leaching slag are obtained; S4, the leachingslag is subjected to desulfuration purification; S5, a gold lixiviant is used for carrying out gold extraction on purifying slag. The advantages of a roasting method and a mechanical activated leaching method are combined, and the beneficial effects of being high in raw material adaptability, gentle in operation condition, low in equipment requirement, obvious in environment and economic benefitand the like are achieved.

Leaching of copper from minerals containing sulfur and copper is hampered by the formation of sulfur on the surface of the mineral during conventional processing. An improved method for extracting copper from a sulfur-containing copper mineral is provided, comprising adding a lixiviant and a silica-containing or titanium-containing compound to a sulfur-containing copper mineral.

A process for recovery of metal comprising copper and/or a precious metal from a metal containing material, including the steps of: leaching the metal containing material with an alkaline lixiviant and an amino acid or derivative thereof in order to produce a metal containing leachate; and extracting the metal from the leachate.

A heap leach process for the recovery of nickel and cobalt from a lateritic ore, said process including the steps of leaching and/or agglomerating the ore with a lixiviant that includes ferrous ions, wherein the lixiviant is able to liberate cobalt from the cobalt containing minerals within the ore in preference to nickel, to produce a cobalt rich pregnant leach solution relatively free of nickel.

Hydrometallurgical systems, methods, and compositions are described in which amine-based lixiviants are utilized in substoichiometric amounts to recover alkaline earths from raw or waste materials. The lixiviant can be regenerated and recycled for use in subsequent iterations of the process or returned to a reactor in a continuous process. Extraction of the alkaline earth from the raw material and precipitation of the extracted alkaline earth is performed in the same reactor and essentially simultaneously.

A method for the heap leaching of manganese-containing ores, the method characterised by the steps of: (i) beneficiating the manganese-containing ore and separating into a coarse fraction and a fine ore fraction; (ii) combining the fine ore fraction with a sulfide ore material to produce a combined ore fraction; (iii) stacking the combined ore fraction to form at least one heap; and (iv) applying a lixiviant to the heap to produce a pregnant leach solution (PLS) containing dissolved manganese values, wherein the lixiviant is added to the or each heap in the presence of soluble iron.

Systems and methods are described in which spent pickle liquor from metal cleaning processes is utilized to regenerate a lixiviant used to recover valuable metals from industrial waste and other sources. The spent pickle liquor is neutralized and solvated metals in the spent pickle liquor are precipitated in this process. When the industrial waste is slag from a metal refining process a partially closed metal production process can be implemented, where spent pickle liquor from cleaning of the refined metal is used to regenerate a lixiviant used to recover a different, valuable metal from a waste slag of the process, with precipitated salts from the lixiviant regeneration being returned as a raw material in the metal refining process. As a result waste streams from these processes are dramatically reduced or eliminated.

A method of recovering gold from carbon fines in a resin-in-leach process wherein the fines are contacted with an ion exchange resin, in the presence of a suitable lixiviant, to load gold onto the resin, eluting the gold from the resin using a suitable eluent and recovering the gold from a resulting eluate.