42results about How to "Low leaching temperature" patented technology

The invention discloses a comprehensive recycling method for a limonite containing nickel, which is characterized by including the following steps: pressurizing and leaching are carried out on the ore material particles of the limonite containing nickel by using a mixed liquid of vitriol and nitric acid as a medium so as to prepare a leaching liquid; aluminum hydroxide, nickel hydroxide, cobalt hydroxide and magnesium hydrate are respectively deposited through using CaO or lime hydrate as a neutralizing agent and controlling the different pH values of the leaching liquid. The method realizes the comprehensive utilization of nickel, cobalt, aluminum, magnesium and iron in the limonite containing nickel; a pressurizing and leaching technique is adopted in a vitriol plus nitric acid medium; the leaching temperature and the leaching pressure are low, wherein, the iron is deposited into the slag in a hematite form, thus effectively inhibiting the leaching of the iron; the settlement performance of a soaked ore slurry is good; liquid-solid separation is easy; the CaO or the lime hydrate is adopted for depositing the aluminum, nickel, cobalt and magnesium by steps; and the leaching agent of the nitric acid can be recycled. The method has the advantages of high operating factor of resources, low energy consumption, environment friendliness, and the like.

The invention relates to the field of non-ferrous metallurgy and resource recycling, in particular to a novel process for extracting vanadium from vanadium-containing waste catalyst reductive organic acid. The novel process comprise the steps that a vanadium-containing waste catalyst is directly extracted in a reductive organic acid system, and other reductive agents are not added, so that pentavalent or tetravalent vanadium is directly reduced into vanadium-oxygen-based ions or trivalent vanadium ions, the vanadium-oxygen-based ions or the trivalent vanadium ions are combined with organic acid radical anions and enter a solution, and vanadium-containing leaching liquid and vanadium-containing leaching slag are obtained; and ammonia water is added into the vanadium-containing leaching liquid to adjust pH so that ammonium vanadate can be formed and precipitated, and after separating is conducted, a vanadium pentoxide product is obtained by calcining precipitation slag. According to the novel process for extracting the vanadium from the vanadium-containing waste catalyst reductive organic acid, the vanadium is extracted by adopting the reductive organic acid system; the extracting condition is mild; the vanadium extracting rate is 95% or above and higher than the direct inorganic acid fluid extracting rate; and other impurity ions are not introduced in the extracting process, so that recycling of other metal elements in the waste catalyst is not affected.

The method for extracting copper from copper-bearing sulfide mineral is characterized by leaching copper-bearing mineral under the condition of introduction of oxygen and in the presence of sulfuric acid and chlorine ion, the liquid-solid ratio of leaching-out liquor is 1-8:1, primary concentration of sulfuric acid is 5-70 g/L, leaching total pressure is 200-1000 kPa, partial pressure of oxygen is 100-800 kPa, temp. is 100-130 deg.C and time is 1-4 hr. The leaching temp. and pressure of said method are low, its selectivity is good, the pyrite can not be oxidated, and the harmful impurity, for example arsenic, can be solidifed in arsenic-ion slag, so that it is a process friendly to environment.

The invention provides an efficient and clean molybdenum smelting method. The method comprises the steps that lime sulphur-fixed roasting is conducted on molybdenite through a gradient heat preservation method; roasted products are leached with a leaching agent, namely roasted product, and molybdenum-contained leach liquid is obtained; the molybdenum-contained leach liquid is sequentially treated by an acid phosphorus extraction system for extracting molybdenum, and an ammonium hydroxide/ammonium salt system for back-extracting molybdenum, and molybdenum-contained strip liquid and molybdenum raffinate are obtained; impurities in the molybdenum-contained strip liquid are removed through a Mg(OH)2 one-step precipitation method, evaporation and concentration are conducted, and ammonium molybdate products are obtained; and sulfuric acid is added into the molybdenum raffinate for regeneration, calcium sulphate dihydrate products are obtained, and regenerated liquid serves as a leaching agent and is returned back to the leaching process. By the adoption of the method, molybdenum mineral raw materials can be cleaned and treated efficiently, and ammonium molybdate can be prepared, the molybdenum recovery rate reaches 99%, the sulfur fixing rate reaches 98% or over, reagent consumption is low, the production period is short, the process is easy to control, the reaching residue quantity is greatly reduced, zero emission of waste water is achieved, and industrialized application is achieved easily.

The invention relates to a method for strengthening agitation leaching of cuprite red copper ore type copper oxide. For copper oxide ore which is fine in ore granularity, low in content of calcium and magnesium existing in the form of carbonates, ozone and hydrogen peroxide are added to ore pulp for heating sulfuric acid leaching; with the addition of an active oxidant, the leaching temperature is reduced, the leaching time is shortened, the leaching efficiency is improved and the leaching cost is reduced; therefore, the cuprite red copper ore type copper oxide difficult to be treated is recycled economically and efficiently.

The invention relates to a method for producing low-temperature soybean meal by the leaching method, belonging to the food industry low-temperature soybean meal production field. The method takes a soybean slice as a raw material and uses pentane as leaching solvent to perform degreasing, and then wet meal is obtained; and the wet meal enters into a desolventizer-toaster for vacuum low-temperature exsolution, and then the low-temperature soybean meal is obtained. The leaching temperature is between 15 and 35 DEG C, the leaching time is between 20 and 35 minutes and the leaching frequency is 3; the residual oil rate of the soybean meal is reduced to below 1 percent; the vacuum degree of exsolution of the wet meal is between 73 and 86 kPa; the exsolution temperature is between 40 and 60 DEG C and the exsolution time is between 0.5 to 1 hour; the residual oil rate of the low-temperature soybean meal produced can reach blow 1 percent and residual solvent is below 200 milligrams per kilogram; and the NSI value of proteins of the soybean meal exceeds 80 percent. The low-temperature soybean meal produced by the method has high protein content, complete shape, white color and no foreign odor.

The invention discloses a clean metallurgical process for preparing ammonium molybdate by using molybdenite concentrate. The clean metallurgical process abandons a traditional limestone baking-ammonium carbonate solution leaching method so that an ammonium sulfate solution in mother liquor does not generate a low-value sulfide ammonium byproduct discharged from a production system, but cheap calcium carbonate which is easy to get is added and is efficiently transformed into an ammonium carbonate solution to realize circulation of ammonium/ammonia in the system; therefore all solutions in the system can be cyclically utilized, the intermediate product is polyammonium molybdate obtained by means of acid precipitation, and thus convenience can be provided for a subsequent molybdenum product preparation process. The clean metallurgical process specifically comprises the following steps: preparation of raw materials; oxidization and baking; pretreatment; leaching, purification and separation of ammonium salt; acid precipitation and separation; transformation and separation of the ammonium salt; recycle and adsorption, wherein NH3 and CO2 gases obtained in the production process are absorbed to obtain the ammonium carbonate solution, and a proper amount of ammonia water is replenished to prepare an ammonium salt solution leaching agent required by the leaching step. The clean metallurgical process disclosed by the invention is low in production cost and high in production efficiency.

The invention discloses a method for extracting valuable metal from copper nickel sulfide through ammonium persulfate-sulfuric acid oxidation leaching. The method comprises the steps of screening low-grade copper nickel sulfide raw materials to obtain copper nickel sulfide mineral powder, according to the proportion, taking ammonium persulfate and sulfuric acid raw materials, adopting one (1) of the two manners in the ammonium persulfate to be completely mixed with sulfuric acid to form a mixture, and then uniformly mixing the mixture with mineral powder according to the proportion; and secondly, enabling the ammonium persulfate to be partly mixed with the sulfuric acid, partly making a saturated solution, under the specific temperature and system pH, performing a constant-temperature leaching reaction, in the leaching process, adding a saturated ammonium persulfate solution, finishing leaching and filtering, and obtaining leaching liquid, wherein the extraction rate of valuable metalNi in the leaching liquid is 90.4 to 97.5%, the extraction rate of Cu is 93.4 to 99.9%, and the extraction rate of Co is 92.7 to 99.6%. The method is low in leaching temperature, low in sulfuric acidconcentration, small in use amount, simple in process flow, and wide in application range, ore raw materials are limited by areas, ore, grade and the like, the extraction rate of the valuable metal ishigher, and no SO2 is emitted.

The invention discloses a method for recycling zinc from smelting waste residues. The method comprises the following steps: uniformly mixing the smelting waste residues with calcium hypochlorite, androasting at a high temperature to obtain a roasted product; uniformly mixing one coordination agent in citric acid or citrate with one coordination agent in tartaric acid or tartrate to obtain a coordination mixture, adding water, adding an ammonia water solution and ammonium sulfate after uniformly adding, uniformly mixing to form a coordination leaching agent; putting the obtained roasted product in the coordination leaching agent to subject to ultrasonic reaction to obtain a zinc leaching solution; adding zinc powder into the obtained leaching solution to react for certain time, then, filtering, and performing high-temperature roasting on the obtained filtrate to obtain zinc oxide. While a leaching rate of zinc in the smelting waste residues is guaranteed, impurity irons therein are prevented from leaching out; and the obtained zinc leaching solution can be roasted at a high temperature to directly obtain a high-purity zinc oxide product, so that zinc in the smelting waste residuesis conveniently recycled to apply in the industry.

The invention discloses a method for extracting Fe, Zn and Pb from electric furnace fly ash and utilizing Fe, Zn and Pb in a high-value mode. A large amount of dangerous waste electric furnace fly ash is used as a raw material, oxalic acid is used as a leaching agent, and a complex reaction is performed under the reaction conditions of low temperature and normal pressure, so that the purpose of stepwise separating iron and zinc resources is achieved. Under the conditions that the concentration of the oxalic acid is 5-30%, the liquid-solid ratio is 10:1-50:1, the reaction temperature is 30-90 DEG C and the reaction time is 0.5-4 h, the leaching rate of Fe in the electric furnace fly ash can reach 92% or above, the content of Zn (in terms of ZnO) in leaching residues can reach 36% or above, and the purity of finally obtained ferrous oxalate can reach 97% or above. The method is simple in process, low in energy consumption and low in reaction cost; and the obtained ferrous oxalate and zinc-rich residues have higher additional value, meanwhile, the influence on the environment is smaller, and the method has good market application prospects.

The invention discloses a leaching method of refractory cobalt ore. The leaching method of the refractory cobalt ore comprises the following steps that (1), after a biomass reducing agent is crushed,a sulfuric acid solution is added for hydrolysis, wherein the biomass reducing agent is poplar or straw; (2) a hydrolyzed material is dissolved in water, and then the refractory cobalt ore is placed in for leaching; and (3) the leached material is subjected to solid-liquid separation to obtain a cobalt-containing leachate. In the method, the leaching reducing agent is wide in raw material source,environmentally friendly, low in leaching temperature and short in leaching time. No harmful gas is produced in the leaching process, environmental pollution of enterprises is reduced, the productioncost is reduced, and economic benefits and the yield are improved.

The invention provides a method for selectively extracting cobalt and nickel from nickel sulfide concentrate. The method comprises the following steps: metal elements in the nickel sulfide concentrate are selectively leached through a superfine grinding-oxygen pressure leaching process to obtain nickel sulfide concentrate leachate, wherein the metal elements at least comprise copper, iron, cobalt, nickel, magnesium and calcium elements; an oxidizing agent is added into the nickel sulfide concentrate leachate to generate precipitates containing iron ions, and therefore the iron ions in the leachate are removed through a sodium jarosite method; sodium fluoride is added as a precipitator to carry out precipitation reaction so as to remove calcium ions and magnesium ions in the leachate; and cobalt ions and nickel ions are extracted and separated through an extraction process to prepare a cobalt sulfate product and a nickel sulfate product. According to the method, efficient recycling of the nickel element in the nickel sulfide concentrate is achieved, other metal elements are further utilized to reduce environmental pollution, and the resource utilization rate and the utilization value of raw materials are improved.

The invention discloses a clean metallurgic method for preparing ammonium molybdate from molybdenite concentrates. The traditional limestone roasting and ammonium carbonate solution leaching method is abandoned to ensure that an ammonium sulfate solution in a mother solution does not form a low-value ammonium sulfate byproduct to be discharged from a production system again, but is efficiently converted into an ammonium carbonate solution through adding cheap and available calcium carbonate, so that the circulation of ammonium/ammonia in the system is realized, and furthermore all the solutions in the system can be recycled; in addition, an intermediate product is ammonium polymolybdate obtained through acid precipitation so as to facilitate carrying out a preparation process for a subsequent molybdenum product. The clean metallurgic method concretely comprises the steps of raw material configuration; oxidizing roasting; pretreatment; ammonium salt leaching; purification and separation; acid precipitation and separation; ammonium salt conversion and separation; and recovery and absorption, wherein an ammonium salt solution leaching agent required in the leaching step is prepared by adding the NH3 and CO2 gases obtained in the production process and the ammonium carbonate solution obtained after absorption and replenishing a proper quantity of ammonia water. The clean metallurgic method is low in production cost and high in production efficiency.

The clean metallurgical system for preparing ammonium molybdate from a molybdenite concentrate comprises a raw material preparation device, a clinker generating device, a clinker pretreatment device, an ammonium salt leaching, purifying and separating device, an acid precipitation and separation device, an ammonium salt conversion and separation device and an absorption device, wherein the raw material preparation device is provided with a molybdenite inlet and a calcium carbonate inlet; the clinker generating device is provided with a roaster, an oxygen inlet, a carbon dioxide outlet and a clinker fine-grinder; the clinker pretreatment device is provided with a pretreatment solution outlet and a pretreatment slag outlet; the ammonium salt leaching, purifying and separating device is provided with a leaching agent inlet, a solution purifying and liquid-solid separating device, a coarse ammonium molybdate solution outlet and a leaching residue returning outlet; the acid precipitation and separation device is provided with a precipitator inlet, a solid-liquid separator, a multiple ammonium molybdate intermediate product outlet, an acid precipitation mother liquor outlet and a pretreatment solution inlet; the ammonium salt conversion and separation device is provided with a size solid-liquid separator, a calcium sulfate solid-phase outlet, and an NH3 and CO2 gas outlet; and the absorption device is provided with an NH3 and CO2 gas recovery inlet, a CO2 gas recovery inlet, an ammonia water supplementing inlet and a re-synthesized leaching agent outlet. The clean metallurgical system is low in production cost, high in production efficiency and free from pollution.

The invention provides a method for selectively extracting cobalt and nickel from nickel sulfide concentrate. The method comprises the following steps: metal elements in the nickel sulfide concentrate are selectively leached through a superfine grinding-oxygen pressure leaching process to obtain nickel sulfide concentrate leachate, wherein the metal elements at least comprise copper, iron, cobalt, nickel, magnesium and calcium elements; phosphate is added into the nickel sulfide concentrate leachate to generate iron phosphate slag and phosphate slag precipitates so as to remove iron ions and copper ions in the leachate; sodium fluoride is added as a precipitant to carry out precipitation reaction so as to remove calcium ions and magnesium ions in the leachate; and cobalt ions and nickel ions are extracted and separated through an extraction process correspondingly to prepare a cobalt sulfate product and a nickel sulfate product. According to the method, efficient recycling of the nickel element in the nickel sulfide concentrate is achieved, other metal elements are further utilized to reduce environmental pollution, and the resource utilization rate and the utilization value of raw materials are improved.