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CN-122012928-A - Recovery method for recycling calcium molybdate by cyclic alkaline leaching of waste molybdenum-nickel catalyst

CN122012928ACN 122012928 ACN122012928 ACN 122012928ACN-122012928-A

Abstract

The invention belongs to the technical field of multi-metal resource wet recovery, and discloses a recovery method for recycling calcium molybdate by cyclic alkaline leaching of waste molybdenum-nickel catalyst, which comprises the steps of roasting molybdenum-nickel waste catalyst powder at 400-500 ℃, cooling, grinding and crushing, and (3) obtaining 80-120 meshes of nickel-molybdenum waste catalyst powder, and then carrying out the processes of initial alkaline leaching, neutralization and impurity removal, neutralization and value adjustment, molybdenum precipitation, circulating alkaline leaching and calcium molybdate purification once to obtain an industrial grade calcium molybdate product which can be sold after washing and drying. The invention adopts the waste molybdenum-nickel catalyst as the raw material and the calcium agent as the precipitant, realizes the recycling of alkali and the recovery of molybdenum, and obtains the industrial grade calcium molybdate product.

Inventors

  • LIN HONGFEI
  • HUANG BINGGUI
  • LI WENWEN
  • QIU NENG
  • DU JIANJIA
  • LIU ZENGHAN
  • TAN HENG
  • ZHANG CAITIAN
  • Wei Tianhui
  • ZHOU YONGXIN

Assignees

  • 广西博世科环保科技股份有限公司
  • 广西环保产业发展研究院有限公司

Dates

Publication Date
20260512
Application Date
20260129

Claims (9)

  1. 1. The recovery method for recycling calcium molybdate by cyclic alkaline leaching of waste molybdenum-nickel catalyst is characterized by comprising the following steps: (1) Calcining the catalyst, namely calcining the molybdenum-nickel waste catalyst powder at 400-500 ℃ for 1-2 hours, and then cooling, grinding and crushing to obtain 80-120 meshes of nickel-molybdenum waste catalyst powder for later use; (2) Adding low-temperature roasted molybdenum-nickel dead catalyst powder into purified water to prepare slurry, adding initial alkali liquor and cosolvent, carrying out solid-liquid separation after heating reaction for a period of time to obtain initial alkaline leaching slag and initial alkaline leaching liquor, and carrying out open-circuit separation on nickel-aluminum slag by the initial alkaline leaching slag; (3) Adding waste catalyst powder into alkaline leaching solution in the step (2) for neutralization and impurity removal, and carrying out solid-liquid separation after the neutralization reaction is finished to obtain impurity-removed slag and impurity-removed liquid; (4) Adding molybdenum-nickel dead catalyst powder into the impurity removal liquid in the step (3), carrying out neutralization adjustment, carrying out solid-liquid separation after the reaction is finished to obtain neutralization slag and neutralization liquid, returning the neutralization slag to the initial alkaline leaching process in the step (1), and allowing the neutralization liquid to enter a calcium oxide molybdenum precipitation process; (5) Adding lime emulsion to the neutralization solution in the step (4) for molybdenum precipitation and the secondary molybdenum precipitation solution in the step (7), filtering to obtain coarse calcium molybdate precipitation and primary molybdenum precipitation solution, and allowing the primary molybdenum precipitation solution to enter a circulating alkaline leaching process; (6) Adding molybdenum-nickel waste catalyst into the solution after molybdenum deposition, adding sodium hydroxide solution according to the end point pH value, heating, carrying out cyclic alkaline leaching, filtering after the reaction is finished for a period of time to obtain alkaline leaching slag and alkaline leaching liquid, carrying out nickel-aluminum slag open-circuit on the alkaline leaching slag, mixing the alkaline leaching liquid with the impurity removal liquid obtained in the step (3), and then entering the step (4) of neutralizing and regulating the value, thus recycling; (7) And (3) purifying calcium molybdate, namely pulping the crude calcium molybdate obtained in the step (5), adding the crude calcium molybdate into the neutralization solution obtained in the step (4), reacting, filtering to obtain purified industrial calcium molybdate and secondary molybdenum-precipitation solution, and returning the secondary molybdenum-precipitation solution to the step (4).
  2. 2. The method for recycling calcium molybdate by cyclic alkaline leaching of a waste molybdenum-nickel catalyst according to claim 1, wherein in the step (2), the initial alkali solution is sodium hydroxide solution with a mass concentration of 5% -30%, the reaction time is 1-4 hours, the reaction temperature is 70-95 ℃, and the end point pH value is 11.5-13.0.
  3. 3. The method for recycling calcium molybdate by cyclic alkaline leaching of a waste molybdenum-nickel catalyst according to claim 1, wherein in the step (2), the cosolvent is halogen salt, the halogen salt is one or a combination of sodium fluoride, sodium chloride and potassium chloride, and the proportion of the cosolvent is 0.5% -2.0% of the mass of slurry.
  4. 4. The recycling method for recycling calcium molybdate by recycling alkaline leaching of waste molybdenum-nickel catalysts, which is characterized in that the pH value of the waste molybdenum-nickel catalyst powder added in the step (3) is adjusted to 8.0-8.5, the impurity removal reaction time is 1-3 h, and the impurity removal reaction temperature is 70-95 ℃.
  5. 5. The recycling method for recycling calcium molybdate by recycling alkaline leaching of waste molybdenum-nickel catalysts, which is characterized in that the pH value of the waste molybdenum-nickel catalyst powder added in the step (4) is adjusted to 7.0-8.0, the neutralization reaction time is 2-4 h, and the reaction temperature is 70-95 ℃.
  6. 6. The recycling method for recycling calcium molybdate by cyclic alkaline leaching of waste molybdenum-nickel catalysts is characterized in that the concentration of lime milk added in the step (5) is 8% -15%, the end point pH value is 12.0-12.5, the reaction time is 10-60 min, and the reaction temperature is normal temperature.
  7. 7. The recycling method for recycling calcium molybdate by cyclic alkaline leaching of waste molybdenum-nickel catalysts according to claim 1, wherein the mass concentration of the sodium hydroxide solution in the step (6) is 5% -30%, the reaction time is 1-4 hours, the reaction temperature is 70-95 ℃, and the final pH value is 11.5-13.0.
  8. 8. The method for recycling calcium molybdate by recycling alkaline leaching of waste molybdenum-nickel catalyst according to claim 1, wherein the calcium molybdate purification reaction time in the step (7) is 1-2 h, the reaction temperature is normal temperature, and the end point pH value is 10.5-11.0.
  9. 9. The recycling method for recycling calcium molybdate by cyclic alkaline leaching of waste molybdenum-nickel catalyst according to claim 1, wherein in the step (2), the mass ratio of the molybdenum-nickel waste catalyst powder to water is 1:8-12.

Description

Recovery method for recycling calcium molybdate by cyclic alkaline leaching of waste molybdenum-nickel catalyst Technical Field The invention relates to the field of multi-metal solid waste recycling, in particular to a recycling method for recycling calcium molybdate by recycling alkaline leaching of a waste molybdenum-nickel catalyst. Technical Field The catalyst can accelerate chemical reaction rate and improve production efficiency through key active components, and is widely applied to the processes of Hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and Hydrodearomatics (HDA) reactions in the fields of petroleum refining, automobile tail gas purification treatment, chemical industry smelting and the like, and the use ratio is more than 90%. In the use process of the catalyst, impurities such as sulfur, phosphorus, arsenic and the like are combined with active sites to form stable compounds to cause catalyst poisoning, or carbonaceous deposits cover the active sites or block pores to cause catalyst failure, the catalyst is usually required to be replaced periodically, every 2-4 years, and the catalyst replaced in periodic overhaul is a spent catalyst. The waste catalysts become dangerous solid wastes, and if the waste catalysts are directly buried, the waste of resources and the environmental pollution are caused, and particularly, the high-value metals in the waste catalysts are huge urban mines, so that the waste catalysts are worthy of recycling. Therefore, the recycling of the spent catalyst can not only improve the local resource utilization rate and recycling level, realize energy conservation and carbon reduction, but also drive the technical progress of the industry in China, promote the standard integration of the secondary resource recovery industry of noble metals and nonferrous metals and the support of related industrial policies, strengthen the comprehensive strength of the country, realize technological innovation and have important significance. The traditional pyrometallurgy has the disadvantages of extremely high energy consumption, serious equipment corrosion, easy secondary pollution and the like because valuable metals are enriched through high-temperature smelting, and the traditional pyrometallurgy is gradually replaced by a wet method and is only used for large-scale rough recovery. The waste agent recovery and resource utilization technological path is mainly combined by adopting a fire method and a wet method, and is pretreated by adopting a rotary kiln, a roasting furnace and the like, oil-containing organic matters and the like in the waste agent are incinerated, and the obtained valuable metal-containing residues are enriched by adopting a smelting system to produce crude alloy for sale. The Chinese patent application number is 202510645819.1, which discloses a method for recycling valuable metals from a vanadium-molybdenum-containing dead catalyst, the method comprises the steps of roasting the vanadium-molybdenum-containing dead catalyst at 180-200 ℃, continuously heating to 450-500 ℃, cooling to obtain a roasting material, mixing the roasting material with sulfuric acid solution A containing oxalic acid, heating to 50-60 ℃ for leaching to obtain a leaching solution A and residues A, mixing the residues A with sulfuric acid solution B containing thiourea and ethylenediamine tetraacetic acid, heating to 70-80 ℃, carrying out secondary leaching to obtain the leaching solution B and residues B, washing the residues B with acid solution to obtain a water washing solution, merging the leaching solution and the water washing solution to obtain a merging solution, S3, adjusting the pH value of the merging solution to 2.5-3, adjusting the pH value to 4.5-5, adding a glyoxime alcohol solution, heating to 35-45 ℃ to obtain a purifying solution, uniformly mixing the purifying solution with the extracting solution to obtain a vanadium-molybdenum-containing organic phase, and S4, carrying out back extraction and preparing products. The method needs to be heated and cooled for many times, and has different wet reaction temperatures and complicated temperature control. The Chinese patent application number is 202011509206.9, and discloses a method for recovering vanadium, molybdenum, nickel and aluminum from petroleum refining waste catalyst, which comprises the steps of carrying out vacuum pyrolysis on the waste catalyst to remove oil, solid waste and heavy oil, carrying out ore grinding, carrying out desulfurization and decarbonization roasting on obtained ore grinding residue to obtain calcine, carrying out sodium roasting on the calcine, leaching the obtained sodium clinker to obtain vanadium, molybdenum solution and nickel and aluminum residue, carrying out adsorption and desorption on the vanadium, molybdenum solution in sequence to obtain molybdic acid and waste liquid, and carrying out pressurized alkaline leaching on the nickel and aluminum residue to realize recovery of