A kind of from phosphorus ore the method for rare-earth enrichment recovery
Technical field
The present invention relates to a kind of from phosphorus ore the method for rare-earth enrichment recovery, particularly decompose and contain the rare earth phosphorus ore and produce in the process phosphoric acid method of rare-earth enrichment recovery from phosphorus ore with sulfuric acid.
Background technology
The rare earth element of occurring in nature also has a sizable part and phosphatic rock and the symbiosis of phosphorite ore deposit except in tax the exists various rare-earth mineral.World's phosphorus ore total reserves is about 1,000 hundred million tons, is 0.05% estimation by the rare earth average content, and association rare earth total reserves can be 5,000 ten thousand tons in world's phosphorus ore.The rare earth that reclaims in the phosphorus ore is originated as a kind of potential rare earth, and is significant.
At present, according to the kind of used acid in the Wet-process Phosphoric Acid Production, the main method that reclaims rare earth in the world from phosphorus ore has: (1) nitrate method; (2) salt acid system; (3) sulfuric acid process.In general, the comprehensive rare earth that reclaims has the high characteristics of yield in the nitrophosphate fertilizer method technology, and to the pure phosphoric acid that contains rare earth, the rare earth yield can reach more than 85% from phosphorus ore, and from the phosphorus ore to the rareearth enriching material, total recovery can reach about 70%.In addition, this method is little to the phosphorous chemical industry process influence, and chemical raw material consumes low, so on-road efficiency is good.But nitrophosphate fertilizer preparation technology mainly is applicable to high-quality phosphate rock resource, and along with phosphate rock resource constantly is exploited, the world is just turning to low-quality phosphorus ore to the utilization of phosphorus at present.World's phosphorous chemical industry facts have proved that this method treatment process has no longer had economic advantages on low-quality phosphorus ore is handled.
Generate phosphoric acid and water-insoluble crystal of calcium sulfate with the sulfuric acid decomposing phosphate rock, this is the present main method of Wet-process Phosphoric Acid Production in the world.In leaching process, phosphorus ore middle-weight rare earths element enters phosphoric acid solution and influenced by leaching condition with the ratio that the generation precipitation enters phosphogypsum, therefore relates to and reclaims rare earth and two kinds of technologies of recovery rare earth from phosphogypsum from phosphoric acid.Various countries have mainly carried out the research of handling recovery rare earth the depleted phosphogypsum of back from the phosphorus ore sulfuric acid wet process at present.Russia has announced that in disclosed patent RU2225892C1 in 2002 sulfuric acid of a kind of 20-25% of employing leaches the technology that reclaims the phosphogypsum middle-weight rare earths, adopt heating concentrated vitriol leach liquor again and add the crystal seed mode, impel crystallization to separate out rareearth enriching material, transfer nitric acid or rare earth chloride to nitrocalcite or calcium chloride processing again, filtrate the returning behind the filtration rare earth crystal is used for phosphogypsum and leaches.The technology that magnesium oxide or magnesiumcarbonate neutralization precipitation sulfuric acid middle-weight rare earths are adopted in the patent RU2158317 proposition that Russia announced in 2000, Russia proposes directly to handle the technology that the dissolving rareearth enriching material adopts oxalic acid precipitation again with nitric acid or hydrochloric acid in the patent RU2148019 that announced in 2000.Poland researchist has reported that also the employing dilute sulphuric acid leaches phosphogypsum, and leach liquor obtains to contain rare earth 10-18% enriched substance through evaporation concentration, adopts hydrofluoric acid precipitation or NPPA solvent extration to prepare Purity of Rare Earth greater than 40% enriched substance again.The J.S.Preston in South Africa proposes to adopt the rare nitric acid that adds nitrocalcite to leach rare earth from half water phosphogypsum slurry, leaching yield can reach 85%, adopt dibutyl butyl phosphonium salt Shellsol2325 from leach liquor, to extract again and reclaim rare earth, prepare the mishmetal of 1600 kilograms of 89-94% altogether.Extract rare earth from phosphogypsum, though feasible technically, flow process is very complicated, and bigger difficulty is arranged economically.
At recovery trace rare-earth from sulfuric acid wet process phosphoric acid research is arranged also in the world, carry in the uranium process, take into account the recovery of rare earth but mainly concentrate on extraction.Under normal Wet-process Phosphoric Acid Production condition, the enrichment of phosphoric acid middle-weight rare earths only is 20%~30%.France Rhone-Poulenc Chimie de Base has invented a kind of from the process of phosphorus ore Wet-process phosphoric acid (WPPA), reclaim the method (US4636369) of metals such as uranium, yttrium, thorium and rare earth, this invention is pointed out, when phosphorus ore adopts sulfuric acid to decompose, uranium in the phosphorus ore dissolves fully and enters solution, and metals such as rare earth, yttrium and thorium only have minimal amounts of dissolved to enter solution in the acidolysis process.In order to realize the unified metals such as uranium and rare earth that reclaim from phosphoric acid solution, when the sulfuric acid decomposing phosphate rock, in ore pulp, introduce aluminum ion, iron ion, silicon ion or its hybrid ionic, can increase the solubleness of rare earth in solution, the highest enrichment of this rare earth only is 56% at present, and, directly influence the subsequent technique of phosphoric acid by wet process in production process of phosphoric acid because the silicon plasma of introducing is a detrimental impurity.
In a word, reclaiming the problem that exists in the trace rare-earth technology from phosphorus ore is: extract rare earth from phosphogypsum, though feasible technically, flow process is very complicated, and bigger difficulty is arranged economically; Reclaim rare earth from phosphoric acid, phosphoric acid middle-weight rare earths enrichment is lower, and research level does not meet technology and requirement economically only up to about 60% at present.
Summary of the invention
The objective of the invention is at low characteristics and the deficiencies in the prior art of China's phosphorus ore middle-weight rare earths content, abandon the method for expensive recovery rare earth from sour wet processing phosphorus ore waste one phosphogypsum, providing a kind of is to decompose with sulfuric acid to contain the method that the rare earth phosphorus ore is produced rare-earth enrichment recovery in the process phosphoric acid.Adopting active additive to suppress rare earth runs off in phosphogypsum, impel most of rare earth element to be enriched in the phosphoric acid system, guaranteed under the prerequisite that does not change the sulfuric acid wet process flow process, realized the low-cost comprehensive purpose that reclaims rare earth, realized that rare earth reclaims effective combination of technology and phosphorous chemical industry technology.
Purpose of the present invention is realized by following technical scheme:
A kind of from phosphorus ore the method for rare-earth enrichment recovery, this method is: handle at sulfuric acid wet process and contain in the process that the rare earth phosphorus ore prepares phosphoric acid, improve the enrichment of rare earth in phosphoric acid by adding calcium sulfate crystal seed and/or active additive, make most of rare-earth enrichment process Separation and Recovery in phosphoric acid.Concrete steps are as follows: add entry or phosphoric acid and stir the reaction of sizing mixing in certain temperature range in phosphorus ore, add calcium sulfate crystal seed and/or additive, add the vitriol oil then, stirring reaction 0.1~50 hour, ageing 0.01~50 hour, filtration obtains phosphoric acid and phosphogypsum, the enrichment of rare earth in phosphoric acid can reach more than 80%, even more than 90%, more even reach more than 95%, phosphogypsum water or weak acid scrubbing, the filtrate that obtains can be returned and size mixing.
The quality liquid-solid ratio that adds in phosphorus ore among this preparation method behind entry or the phosphoric acid is 1: 1~10: 1, and preferred 3: 1~6: 1, the phosphoric acid concentration that adds in phosphorus ore was 0.01wt%~40wt%P
2O
5, preferred 20wt%~25wt%.Add in phosphorus ore that the stirring reaction time is 0.5~8 hour behind entry or the phosphoric acid, preferred 1.5~3 hours.
Adding the calcium sulfate crystal seed is 0.1%~30% of phosphorus ore quality, preferred 10%~20%.Additive is organic additive and/or inorganic additives, wherein organic additive is sodium laurylsulfonate, Sodium dodecylbenzene sulfonate anion active additive, cetyl trimethylammonium bromide cation activity additive, at least a in polyacrylamide, polyoxyethylene glycol, the polyvinyl alcohol nonionic additives, optimization polypropylene acid amides, polyoxyethylene glycol, polyvinyl alcohol nonionic additives, inorganic additives are sodium polyphosphate, (NH
4)
2SO
4, Na
2SO
4, NaCl, NH
4Cl, NH
4NO
3, NaNO
3In at least a, preferred (NH
4)
2SO
4Additive, additive amount are the 0.0001wt%~8wt% of phosphorus ore, preferred 0.1wt%~3wt%.
The stirring reaction temperature is 20 ℃~85 ℃, preferred 50~75 ℃.The used sulfuric acid of decomposing phosphate rock is that concentration is 90%~98%H
2SO
4, add the metering of vitriolic chemical quality than being 0.85~1.30, preferred 1.05~1.10.Washing is 0.0001~3molL with dilute sulphuric acid concentration
-1, preferred 0.2~1molL
-1
In principle, to being applicable to phosphorus ore of the present invention without limits, as long as it contains rare earth element.But,, will influence the economy of method of the present invention if the content of rare earth element is too low.Usually, be applicable to that phosphorus ore middle-weight rare earths content of the present invention should be 0.01wt ‰ at least, to the upper limit of ree content without limits, content of rare earth REO after the enrichment in the phosphoric acid is 0.01-5g/L, adopt one or both method separation and Extraction in extraction process, chromes, ion exchange method precipitation, the crystallization process, obtain the mishmetal enriched substance.。
In the sulfuric acid wet process phosphorite process and nitrophosphate fertilizer method when handling phosphorus ore, rare earth mainly exists with the rare-earth phosphorate form, the solubility product constant of rare-earth phosphorate is less, easily eutectic and the adsorption because of calcium sulfate enters in the phosphogypsum in the sulfuric acid wet process process, thereby cause rare earth enrichment in phosphogypsum, therefore by the control suitable process conditions, particularly by adding tensio-active agent, can improve the crystal habit of phosphogypsum, reduce eutectic and adsorption, minimizing is beneficial to and reclaims rare earth from phosphoric acid to the phosphogypsum enrichment.
Enrichment=the be enriched to total amount of rare earth in the rare earth/phosphorus ore in the phosphoric acid.
Effect of the present invention and advantage are:
At the low characteristics of China's phosphorus ore middle-weight rare earths content, abandon the method for expensive recovery rare earth from sour wet processing phosphorus ore waste-phosphogypsum, proposing to adopt the promoting agent additive to suppress rare earth first runs off in phosphogypsum, impel most of rare earth element to be enriched in thinking in the phosphoric acid system, guaranteed under the prerequisite that does not change the sulfuric acid wet process flow process, realized the low-cost comprehensive purpose that reclaims rare earth.Traditional sulfuric acid wet process is handled in the phosphorite process, rare earth element in phosphogypsum the enrichment ratio more than 70%, when reducing the enrichment ratio of rare earth in phosphogypsum, take into account the stability of phosphorous chemical industry production process technology condition, reduce the influence that the rare earth removal process is handled phosphorus ore, realize that rare earth reclaims effective combination of technology and phosphorous chemical industry technology.Compared with prior art, the present invention is by the control suitable process conditions, particularly by adding calcium sulfate crystal seed and/or active additive, can improve the crystal habit of phosphogypsum, reduce the eutectic and the adsorption of rare earth, reduce it, help from phosphoric acid, reclaiming rare earth to the phosphogypsum enrichment.The present invention can satisfy the requirement of Wet-process Phosphoric Acid Production, and technology is simple, and phosphoric acid middle-weight rare earths content height adopts extraction process or precipitated crystal method separation and Extraction, obtains the mishmetal enriched substance, realizes that rare earth reclaims effective combination of technology and phosphorous chemical industry technology.
Concrete embodiment
Below in conjunction with embodiment the present invention further is described:
Embodiment 1:
Under 85 ℃, get the phosphorus ore 100g that contains rare earth 5.51wt ‰, be 4: 1 adding 5%P by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 1.5 hours, add calcium sulfate crystal seed 10g (for phosphorus ore quality 10%) and 0.1g (consumption be phosphorus ore 0.1%) Macrogol 4000 additive, slowly add stoichiometric ratio then and be 0.85 sulfuric acid, stirring reaction 40 hours, ageing 0.1 hour is filtered and is obtained phosphoric acid solution and phosphogypsum, and water washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 1.10g/L, and the amount that rare earth enters in the phosphoric acid accounts for 80.1% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 2:
Under 70 ℃, get the phosphorus ore 100g that contains rare earth 1.28wt ‰, be 4: 1 adding 21%P by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 1.5 hours adds calcium sulfate crystal seed 5g and 0.3g Macrogol 4000 additive, slowly add stoichiometric ratio then and be 1.05 sulfuric acid, stirring reaction 0.5 hour, ageing 35 hours, filtration obtains phosphoric acid solution and phosphogypsum, and water washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 0.25g/L, and the amount that rare earth enters in the phosphoric acid accounts for 80.19% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 3:
Under 70 ℃, get the phosphorus ore 100g that contains rare earth 0.53wt ‰, be 4: 1 adding 25%P by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 3 hours adds calcium sulfate crystal seed 10g and 0.2g polyacrylamide additive, slowly add stoichiometric ratio then and be 1.05 sulfuric acid, stirring reaction 2.5 hours stirs ageing 1 hour, filtration obtains phosphoric acid solution and phosphogypsum, uses 0.5molL
-1Sulfuric acid washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 0.11g/L, and the amount that rare earth enters in the phosphoric acid accounts for 83.02% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 4:
Under 70 ℃, get and contain rare earth 5.51wt ‰ phosphorus ore 100g, be to add 21%P at 3: 1 by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 3 hours adds calcium sulfate crystal seed 15g and 0.3g polyvinyl alcohol additive, slowly adds stoichiometric ratio then and be 1.05 sulfuric acid, stirring reaction 4.5 hours, ageing 5 hours is filtered and is obtained phosphoric acid solution and phosphogypsum, uses 1molL
-1Sulfuric acid washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 1.57g/L, and the amount that rare earth enters in the phosphoric acid accounts for 85.65% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 5:
Under 70 ℃, get and contain rare earth 5.5wt ‰ phosphorus ore 100g, be to add 21%P at 3: 1 by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 3 hours adds calcium sulfate crystal seed 15g and 0.3g Sodium dodecylbenzene sulfonate additive, slowly add stoichiometric ratio then and be 1.05 sulfuric acid, stirring reaction 4.5 hours, ageing 5 hours, filtration obtains phosphoric acid solution and phosphogypsum, uses 1molL
-1Sulfuric acid washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 1.51g/L, and the amount that rare earth enters in the phosphoric acid accounts for 82.3% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 6:
Under 60 ℃, get and contain rare earth 1.28wt ‰ phosphorus ore 100g, be to add 21%P at 6: 1 by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 5 hours adds calcium sulfate crystal seed 15g and 0.3g cetyl trimethylammonium bromide additive, slowly add stoichiometric ratio then and be 1.1 sulfuric acid, stirring reaction 15 hours, ageing 20 hours, filtration obtains phosphoric acid solution and phosphogypsum, uses 0.5molL
-1Sulfuric acid washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 0.18g/L, and the amount that rare earth enters in the phosphoric acid accounts for 84.62% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 7:
Under 50 ℃, get and contain rare earth 1.28wt ‰ phosphorus ore 100g, be to add 21%P at 6: 1 by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 5 hours adds calcium sulfate crystal seed 15g and 1.0g (NH
4)
2SO
4Additive slowly adds stoichiometric ratio and is 1.1 sulfuric acid then, stirring reaction 15 hours, and ageing 20 hours is filtered and is obtained phosphoric acid solution and phosphogypsum, uses 0.5molL
-1Sulfuric acid washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 0.19g/L, and the amount that rare earth enters in the phosphoric acid accounts for 91.34% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 8:
Under 50 ℃, get and contain rare earth 1.28wt ‰ phosphorus ore 100g, be to add 21%P at 6: 1 by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 5 hours adds calcium sulfate crystal seed 15g and 0.3g Macrogol 4000 additive, slowly adds stoichiometric ratio then and be 1.1 sulfuric acid, stirring reaction 15 hours, ageing 20 hours is filtered and is obtained phosphoric acid solution and phosphogypsum, uses 0.5molL
-1Sulfuric acid washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 0.20g/L, and the amount that rare earth enters in the phosphoric acid accounts for 92.57% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.
Embodiment 9:
Under 60 ℃, get the phosphorus ore 100g that contains rare earth 0.53wt%, be 6: 1 adding 21%P by liquid-solid ratio
2O
5Phosphoric acid, stirring reaction 3 hours adds calcium sulfate crystal seed 20g and 0.5g ammonium sulfate, 0.25g Macrogol 4000 additive, slowly add stoichiometric ratio then and be 1.05 sulfuric acid, stirring reaction 10 hours, ageing 20 hours, filtration obtains phosphoric acid solution and phosphogypsum, uses 2molL
-1Sulfuric acid washs phosphogypsum.Content of rare earth REO after the enrichment in the phosphoric acid is 0.85g/L, and the amount that rare earth enters in the phosphoric acid accounts for 95.65% of phosphorus ore middle-weight rare earths total amount.Adopt extraction process or precipitated crystal method separation and Extraction, obtain the mishmetal enriched substance.