é’ªResources and their extraction (in vanadium-titanium magnetite) 2

Scandium ore mainly titaniferous augite, iron titanium and titanium magnetite ore, mineral distribution in the product with the mineral content of the first two changes, in which the occurrence of scandium isomorphous to form. In titanium ordinary pyroxene, Sc3+ replaces Fe2+ and Mg2+ by heterogeneous isomorphism, and the electricity price balance is achieved by replacing Fe3+ and Al3+ with Si4+. The substitution relationship is Sc3+ + Al3+ →(Fe2+,Mg2+)+ Si4+ The isomorphism of the yttrium in the ilmenite is Sc3+ +(Fe3+ + Al3+)→(Fe2+,Mg2+)+ Ti4+ The occurrence is mainly related to the ilmenite and ilmenite spatter. The most abundant of the minerals in the ore dressings is the elective tailings, which contain 77 ppm of Sc2O3, followed by iron concentrates and re-selected tailings, containing 63 ppm and 51.4 ppm of Sc2O3, respectively. A general method for extracting rhodium from these raw materials is outlined below.

1) Electro-selection of tailings and re-election of tailings

It is mainly rich in titanium ordinary pyroxene. There are two main methods for the recovery of pyroxene in China:

Acid treatment - decomposition with sulfuric acid, heating and stirring for 4 ~ 5h, until the SO2 steam is completely eliminated; or with hydrochloric acid (HCl + NaF) decomposition, temperature 80 ~ 100 ° C, treatment 4 ~ 5h.

Alkaline treatment - the minerals are melted together with NaHSO4 and NaOH for 1 h at a temperature of 500-600 °C. The hydrate obtained by the alkali fusion method is filtered and precipitated to remove alkali, and then dissolved by heating in hydrochloric acid. The hydrate is precipitated from the solution with ammonia, filtered and calcined to form an oxide.

2) Titanium concentrate

In the smelting process of titanium concentrate electric furnace, it is mainly enriched in high-titanium slag. When high-titanium slag is further subjected to high-temperature chlorination in a boiling furnace to produce titanium tetrachloride, most of the cerium is chlorinated to ScCl3 and volatilized into soot. After cooling, Collected by the dust collector, the Sc2O3 content can reach 736ppm.

3) Iron concentrate

The grade of niobium in iron concentrate is Sc2O3 20ppm. The trend of niobium in the process of sintering and steel making is mainly concentrated in the slag of ironmaking slag, which can be considered for recovery. The Soviet Union began research in this area in the 1950s, using the alkali-carbonate method to recover strontium from blast furnace slag. That is, the slag is decomposed with sulfuric acid, then the hydroxide is precipitated by alkalization, and the cerium concentrate is prepared by treatment with carbonate. Finally, thiosulfate extraction and oxalate precipitation are carried out, and oxalate is calcined to obtain Sc2O3.

In the 1980s, with the skyrocketing price of the world market, the domestic research and development boom was initiated. The extraction mainly focused on titanium-containing raw materials - sulfuric acid waste liquid for producing titanium dioxide, chlorinated soot during titanium production, and selection. Titanium tailings. Domestic production unit in Shanghai Dongsheng titanium dioxide plant, Guangxi Guangxi Bureau of Mines, Hunan Institute of rare earth metal material, Ganzhou cobalt smelter, such as titanium dioxide plant in Guangzhou. After entering the 1990s, due to the large sale of its past inventory and domestic over-production in the former Soviet Union countries, the world market has been oversupplied, and the price of sputum has been greatly reduced, directly affecting the production of cockroaches. The research and production status of extracting rhodium from titanium-containing raw materials are described below.

(1) Extraction of barium from titanium white waste acid

When the sulfuric acid method produces titanium white powder from ilmenite, the amount of antimony contained in the hydrolyzed acidic waste liquid accounts for about 80% of the total content of the ilmenite. Most of the cerium oxide produced in China comes from titanium dioxide factory. Shanghai Dongsheng Titanium Dioxide Factory and Shanghai Yuelong Chemical Plant and Guangzhou Titanium Dioxide Factory have established a cerium oxide production line. Hangzhou Sulfuric Acid Plant put into operation a set of industrial equipment with an annual output of 30kg of cerium oxide, forming a three-stage enthalpy process route of “continuous extraction—12-stage countercurrent washing titanium-chemical refining”, and the product content is stable at 98~99%. Shanghai Chemical Yuelong using P204-TBP- initial kerosene synergistic extraction Scandium, NaOH stripping, hydrochloric acid was dissolved, and then by 55-62% TBP (or P350) extraction resin scandium extraction chromatography for purification, and finally purified by oxalic acid, The yield of Sc2O3 with a purity greater than 99.9% is greater than 70%.

In the former Soviet Union, 0.4M P204 was used to extract cerium from titanium dioxide mother liquor. When O/A=1/100, the cerium was almost completely separated from impurities such as titanium, iron and calcium. It was decollected with solid NaF and dissolved with 3% H2SO4. The yield of the expanded test cockroach is 85 to 90%. Yang Jian et al. used P204-TBP to extract bismuth from titanium white mother liquor, first added inhibitors, inhibited the extraction of iron and titanium by P204, and then extracted the organic phase with mixed acid and sulfuric acid to reduce the TiO2 content in the organic phase to 0.1. Mg/l, Fe content decreased to 0.5 mg / l. Feng Yanlin and others used P507-N7301-kerosene mixed extractant to extract bismuth, the extraction rate was over 95%, and the purity of secondary oxalic acid precipitation Sc2O3 product was over 99%. Nie Li et al. used two sections to extract, the first stage was extracted with P507-sterol-kerosene, the second stage was extracted with P5709-TBP-kerosene, and the hydrazine was concentrated more than 50 times. Liu Huizhong first used N1923 to selectively extract ruthenium, and then added TBP extract to further remove impurities. The two stages were concentrated more than 50 times. The purity of Sc2O3 after oxalic acid purification was 99%, and the recovery rate was 84%. In addition, the ion exchange method and the emulsion liquid membrane method have also been used for titanium white waste liquid lifting.

(2) Extraction of cesium from chlorinated soot

When high slag in the arc melting ilmenite, because Sc2O3 niobium, uranium, vanadium oxide such as high heat generated, it is very stable and will not be left in the reduction of the titanium slag. When the high-titanium slag is subjected to high-temperature chlorination to produce TiCl4, cerium is enriched in chlorinated soot. Fushun aluminum plant fifty-one branch plant production line production scandium oxide 20 ~ 30kg. Ke Jiajun et al [14] found that the content of strontium in chlorinated soot can reach 0.03~0.12%, the main form is ScCl3; and the process of hydrometallurgical extraction of Sc2O3, including water immersion, TBP kerosene solution extraction, oxalic acid precipitation purification and In the unit operation such as burning, the small and enlarged tests were carried out successively to obtain the Sc2O3 product with a purity of 99.5%; from the chlorinated soot to the product, the recovery rate of hydrazine was 60%. Xie Lina uses a low concentration of alkylphosphine ( phosphoric acid) (P507, P204) to extract hydrazine directly from the presence of a large amount of Fe3+ in a small ratio. Using ethanol as a back stripping agent, the ruthenium can be stripped at room temperature; and the zirconium separation coefficient is 0.4S/Zr=1893 by using zirconium with 0.4% HF. Yang Zhifa et al. used P5709-N235-kerosene extraction ruthenium and 5M HCl 60 °C stripping to completely separate Sc3+ from Fe3+, Fe2+, Ti3+, Al3+, Mn2+, Ca2+, etc., which solved the separation of Sc3+/Fe3+ and slow phase separation. problem. Hejin Lin et al mention when smoke from scandium chloride, extraction and separation using P204 Fe, Mn, NaOH stripping scandium enriched 83-fold; dissolved chemically purified using hydrochloric acid, concentrated hydrochloric acid and extracted TBP- separating scandium and RE Dowex50W- X8 exchange resin钪, the purity of Sc is >99.5%, and the yield is >56%. Sun Benliang et al. used an organic polybasic weak acid precipitant to precipitate hydrazine in the leaching solution of chlorinated soot hydrochloric acid. After two precipitations and two acid hydrolysiss, the removal rate of iron and manganese in the leaching solution was over 99.8%, and the precipitation rate of hydrazine was up to 100%; then P204 + modifier + sulfonated kerosene as extractant, O / A = 1 / 20, extraction of cesium at room temperature, DSc up to 139, the separation coefficient of bismuth and iron, manganese reached 9270 and 10700 respectively; 5% After NaOH stripping, the stripping rate was 99.6%. Lin Weiming et al. used benzylic acid to extract hydrazine, and the yield of hydrazine was 98.3%.

(3) Extraction of strontium from selected titanium tailings

Panzhihua has built a concentrating plant with a designed scale of 13.5 million t/a, with an annual output of 5.883 million tons of iron concentrates and an annual output of 4.5455 million tons of tailings, which is in urgent need of comprehensive utilization. Zhang Zonghua tested the original ore of the iron ore plant at the time of the “Eighth Five-Year Plan” for the comprehensive evaluation of the Panzhihua vanadium-titanium magnetite. The iron ore in the iron ore plant was 27.00 g/t. Calculated according to the design scale, 364.25 tons of 钪 is recovered from the treated ore every year, and its value is 24.425 billion yuan. They scandium containing 63g / t Titanium tailings as raw materials, processing additives or pretreatment magnetic electric separation process can be divided into selected titanaugite tailings, feldspar, containing scandium, respectively 114g / t 121g/t; leaching with leaching solution with hydrochloric acid, the leaching rate can reach 93.64%; the leaching rate can be up to 97.90% by alkali fusion and hydrolysis of hydrochloric acid; the extraction rate can reach 98.90% by TBP extraction; The stripping rate is 98.00%; and then refined with oxalic acid to obtain a Sc2O3 product with a grade of 99.95%, and its market price is 36,000 yuan/kg. Due to the relatively high price and small market capacity, no factory has been built yet.

summary:

In summary, the cerium in the titanium white mother liquor is in an ionic state, and the extraction process is simple, so the early production of cerium oxide is mostly used as a raw material; however, the content of cerium is low (10-25 ppm), and is restricted by the production of titanium dioxide. (The annual output of 1000t titanium dioxide can recover dozens of kilograms of cerium oxide). The ruthenium in chlorinated soot exists in the form of ScCl3, and the recovery is not difficult. The question is whether the chlorinated soot is sufficient. Assuming that the cerium oxide content is 500 ppm on average, to obtain 50kg yttrium oxide product, at least 100t should be processed. Chlorinated soot, the amount of treatment is quite large. In the titanium tailings, the strontium is mainly present in the pyroxite of (Ca, Mg, Al, Ti) Si2O6 silicate structure. The decomposition of tailings is difficult, and it is often melted by acidification or alkalization (~1000 °C); The output of tailings is very large, and the absolute amount of strontium produced is considerable, providing sufficient raw materials for the production of strontium; however, the treatment of tailings must also take into account the comprehensive utilization of other resources.

High Speed Duplex Slitter Rewinders

Dual-Turret Slitter Rewinder Machinee is a very successful narrow width centre winder for slitting BOPP film used principally in the packaging of tobacco products.