CN101054634A

CN101054634A - Stone-like coal salt-free roasting low-alkali leaching solution complementarity oxidation vanadium extracting technique

Info

Publication number: CN101054634A
Application number: CNA2006100314837A
Authority: CN
Inventors: 何旭初
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-04-11
Filing date: 2006-04-11
Publication date: 2007-10-17

Abstract

A process for extracting vanadium through supplementary oxidation of stone coal salt free calcination low alkali leaching solution. This kind of environment protection type process for extracting vanadium comprises the steps of pulverizing vanadium containing stone coal and vanadium containing weathered mine to about 60-80 grits and adding water therein directly (sawed wood chips of 5% are mixed in ball materials directly lixiviated) for granulation under roasting temperature of 900-950 DEG C. At conditions of liquor-solid ratio of 1-1.5, NaOH concentration of 3-4% and leaching temperature of 60 DEG C, the intermittent adverse current typeleaching is performed. The leaching rate is capable of reaching 73%, a vanadium extracting according to routine process, or hydrolytic decomposition vanadium deposition, or vanadium extracting, or ion exchange vanadium extracting is available after the immersion liquid is added with a hydrogen dioxide solution of 2% for supplementary oxidation and impurity removal. Since common salt is not added during the calcination and no noxious gas is generated, the present invention is then a ecology friendly type process. The present invention is easy for compatibility with the existing vanadium extraction process, doesn't need special equipments, and exhibits a vanadium receiving rate equal to or a little higher than the sodium oxidation process and a similar cost.

Description

The stone-like coal salt-free roasting low-alkali leaching solution complementarity oxidation process for extracting vanadium

The present invention is a kind of environment-friendly type technique that extracts Vanadium Pentoxide in FLAKES from contain the scherbinaite coal.Vanadium is a kind of purposes yttrium very widely.Contain in the very abundant bone coal in China, the reserves of its vanadium account for 87% of China's vanadium resource total reserves, have surpassed the summation of external vanadium resource.Therefore, the vanadium extraction of environment-friendly high-efficiency ground is a job of benefiting the nation and the people from bone coal.From last century the seventies extracting vanadium from stone coal formally found the factory so far, its main flow technology is bone coal oxidation sodium roasting-water logging-hydrolysis precipitation (or extraction vanadium extraction or ion exchange extraction vanadium) always.The strong point of this technology is that sodium-chlor (salt) has good selectivity to barium oxide in the bone coal, thereby has avoided accounting in the bone coal participation of the impurity such as silicon-dioxide of main share.But owing to produce a large amount of chlorine and hydrogenchloride toxic gas in its roasting process, cause trees vegetation in blocks withered, the environment of severe contamination human survival is not so allowed by society.As for grow up on this basis with roasting the time salt proportioning reduce to 4.5%～8% less salt technology by 10%～16%, be not eliminated because of still solving the chlorine that the sodium roasting method causes and the problem of hydrogenchloride pollution of ecological environment, also facing.

For this reason, people have invented bone coal calcification baking-diluted acid and have leached process for extracting vanadium and bone coal saltless roasting-diluted acid leaching process for extracting vanadium.The existing producer of these technologies adopts.But further studies show that: the bone coal roasting is under steam heating acidleach condition, and vanadium compounds in the leach liquor tangible backward reaction is arranged, and this reaction pair extracting vanadium from stone coal is disadvantageous.

With the present invention approaching be that the bone coal saltless roasting diluted alkaline that was published in the rare metal magazine in 1994 leaches the laboratory study achievement of vanadium extraction.This achievement fixes on 950 ℃ to the bone coal maturing temperature, and leaching condition is fixed on NaOH concentration 2mol/L (being 11.7wt%), and liquid-solid ratio 4: 1 is soaked about 95 ℃ of temperature.These conditions are inconvenient in practice: because the carbon content under many circumstances in the bone coal roasting material is about in the of 6%, and inaccessible 950 ℃ of its maturing temperature, the vanadium compounds in the raw material is oxidized to V ₂O ₅And not exclusively; In addition, such liquid-solid ratio when actual production, can be that back step operation is made troubles and increased consumption because of the low immersion liquid of content of vanadium, and the 2mol/L alkali concn is also too much simultaneously; Research also shows in addition, soaks after temperature surpasses 60 ℃, and the temperature of increase is very little to the contribution of leaching yield, only 1～2 percentage point.

On this basis, the present invention has kept the strong point of the salt-free oxidizing roasting of bone coal to eco-friendly, and the alkali concn of leach liquor is controlled at 3%～4%, and liquid-solid ratio is 1～1.5: 1 then, and soaking temperature is about 60 ℃, and supplemental is made in immersion liquid handled, to guarantee V ₂O ₅Transform fully.

Test of the present invention is that the vanadium factory at extracting vanadium from stone coal carries out.Bone coal raw ore and bone coal weathered ore are worn into 60～80 purpose powders in about 1: 1 ratio, and reinforced heavy 3%～8% wood sawdust is mixed thoroughly and added water and make bead about diameter 10mm.Dry in the shade the back in common honeycomb briquette kiln roasting, it is abundant to make every effort to oxygen supply during roasting, temperature is leaned on to 900 ℃～950 ℃ as far as possible, make every effort to be the dark grey look to improve leaching yield (seeing example 1) after the pellet roasting, avoid crossing low or the roasting fault taking place too much pink or pellet that colour of loess band is red occurring, because this ball leaching yield very low (seeing example 2) because of maturing temperature.Pellet after the roasting is 1～1.5: 1 (just soaking the Shi Yinqiu suction and capping) with liquid-solid ratio, temperature is soaked in control remains on about 60 ℃ it always, each actual 6h (as when being broken into powdery and stirring being arranged, extraction time can foreshorten to 2～3h, filters operation but will increase).(raw material contains V to the vanadium leaching yield average 73% of pellet when leaching six times ₂O ₅When high, leaching yield is also high).Leaching mode in the practice is that middle temperature is interrupted reverse-flow leaching, and raw material contains V ₂O ₅During 1.0% left and right sides, the V of immersion liquid ₂O ₅Concentration can reach about the 7g/L.The commercially available hydrogen peroxide of adding about 2% in immersion liquid, and be heated to about 60 ℃, make the vanadium compounds in the liquid fully be transformed into the pentavalent vanadium.The process for extracting vanadium operation routinely of ensuing operation, even extraction vanadium extraction, or ion exchange extraction vanadium, or the hydrolysis precipitation.The present invention does not have specific installation, is easy to be connected with old technology.As can transferring with hydrochloric acid about PH to 2, and with being steam heated to, press CaO in the lime and the V in the liquid greater than 80 ℃ through the solution after the supplemental ₂O ₅The ratio 1～2.5 of weight adds granularity and is not more than 2cm lime block (its ratio selectable 1 when lime quality is good), leaves standstill filtration after fully stirring 40min to 1h, the V in this moment liquid ₂O ₅Can reduce to below the 0.17g/L.Under 〉=90 ℃ temperature, with the V in the vanadic acid calcium ₂O ₅About 3 times Tan Suan Qing of weight leaches vanadic acid calcium, and the liquid-solid ratio of its leaching can be greatly, and as 4～5, stirring must be strong, leaches insufficient otherwise have a large amount of vanadic acid calcium because of being sunken to reactor bottom.Stir when abundant, leach that 30min is above to get final product.The V of this immersion liquid₂O ₅Concentration is easy to reach more than the 15g/L, and its pH value is about 8.Because of it contains V ₂O ₅Higher, the direct hydrolysis precipitation is easy to accomplish, promptly with hydrochloric acid pH value is transferred to 1.9～2.2, and is heated to 〉=80 ℃, stirs 40min～1h, can obtain the hydrolysis prods that composition is an ammonium poly-vanadate, the oven dry roasting get final product high-quality Vanadium Pentoxide in FLAKES.The vanadium total recovery of technology is 50%～60%, looks raw material and fluctuates.

Be the bone coal of the present invention below with the Hunan, each time laboratory values that pellet directly leaches according to above-mentioned condition behind the saltless roasting.Example 1, raw material contains V ₂O ₅Be 1.48%, roasting is normal, and pellet is the dark grey look, for the first time alkali immersion liquid V ₂O ₅: 5.4g/L, for the second time: 3.23g/L, for the third time: 1.52g/L, the 4th time: 0.9g/L, the 5th time; 0.41g/L, the 6th time: 0.31g/L, soak the back pellet and contain V ₂O ₅: 0.14%.Example 2, raw material contains V ₂O ₅Be 0.98%, roasting is out of order, pellet be the colour of loess redly, immersion liquid for the first time, V ₂O ₅: 2.08g/L, for the second time: 1.19g/L, for the third time: 0.92g/L, the 4th time: 0.46g/L, the 5th time: 0.4g/L, the 6th time: 0.5g/L, soak the back pellet and contain V ₂O ₅Be 0.43%.

Claims

1, a kind of environment-friendly type technique of vanadium extraction from contain the scherbinaite coal, to contain the scherbinaite coal or to be raw material with the mixing ore deposit that contains the scherbinaite coal and contain the vanadium weathered ore, through pulverizing the granulation roasting and leaching vanadium extraction, the invention is characterized in: behind raw material pulverizing to 60～80 orders not with salt, granulate autogenous roasting and add 3%～8% wood sawdust.Pellet after the roasting leaches in the NaOH of lower concentration solution under mesophilic condition, pellet can not pulverized during leaching, also can be pulverized (then not adding wood sawdust when leaching),, be increased corresponding filtration operation though finely powdered calcining extraction time can shorten at double with powder; Before from immersion liquid, proposing vanadium compounds, need the low price vanadium in the immersion liquid fully to be oxidized to the pentavalent vanadium with a spot of oxygenant such as hydrogen peroxide or clorox; Technology is carried out routinely thereupon, even extraction vanadium extraction, or ion exchange extraction vanadium, or the hydrolysis precipitation.

2, technology according to claim 1 is characterized in that not adding salt in the bone coal roasting material, and mixes 3%～8% fine-grannular combustiblesubstance, as wood sawdust, cavings etc. make that the material grain is vesicular after the roasting, help liquid and infiltrate (then not adding wood sawdust when leaching with powder).

3, according to claim 1,2 described technologies, its feature is that also the concentration of NaOH in the leach liquor can reduce to 2.5%, but is advisable with 3%～5%, soaks temperature and is higher than room temperature, as 40 ℃～70 ℃.

4, according to claim 1,2,3 described technologies, its feature also is in order to improve the quality and quantity of extraction vanadium compounds from immersion liquid, in immersion liquid, added a spot of oxygenant, as hydrogen peroxide, clorox, permanganate and so on, when for example adding commercially available hydrogen peroxide, its amount is 0.5%～4% of liquid measure.