EP0085728A1 - Procédé pour le broyage de minerais de titane pour exalter le rendement du dioxyde de titane - Google Patents
Procédé pour le broyage de minerais de titane pour exalter le rendement du dioxyde de titane Download PDFInfo
- Publication number
- EP0085728A1 EP0085728A1 EP82100910A EP82100910A EP0085728A1 EP 0085728 A1 EP0085728 A1 EP 0085728A1 EP 82100910 A EP82100910 A EP 82100910A EP 82100910 A EP82100910 A EP 82100910A EP 0085728 A1 EP0085728 A1 EP 0085728A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- ore
- titanium dioxide
- polyol
- titaniferous
- comminution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 title abstract description 46
- 239000004408 titanium dioxide Substances 0.000 title abstract description 23
- 238000011084 recovery Methods 0.000 title abstract description 16
- 238000000227 grinding Methods 0.000 title description 4
- 229920005862 polyol Polymers 0.000 claims abstract description 22
- 150000003077 polyols Chemical class 0.000 claims abstract description 22
- 125000002947 alkylene group Chemical group 0.000 claims abstract description 4
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims abstract description 4
- 125000002768 hydroxyalkyl group Chemical group 0.000 claims abstract 3
- 238000000034 method Methods 0.000 claims description 15
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 7
- 239000002245 particle Substances 0.000 claims description 7
- 125000000325 methylidene group Chemical group [H]C([H])=* 0.000 claims description 5
- 125000000217 alkyl group Chemical group 0.000 claims description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 31
- 230000029087 digestion Effects 0.000 description 9
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 6
- 239000010936 titanium Substances 0.000 description 6
- 229910052719 titanium Inorganic materials 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 238000003556 assay Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- WXZMFSXDPGVJKK-UHFFFAOYSA-N pentaerythritol Chemical compound OCC(CO)(CO)CO WXZMFSXDPGVJKK-UHFFFAOYSA-N 0.000 description 2
- 239000000049 pigment Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- LDVVTQMJQSCDMK-UHFFFAOYSA-N 1,3-dihydroxypropan-2-yl formate Chemical compound OCC(CO)OC=O LDVVTQMJQSCDMK-UHFFFAOYSA-N 0.000 description 1
- PUWSPTQNHGUGDZ-UHFFFAOYSA-N 2,2-bis(hydroxymethyl)butane-1,3-diol Chemical compound CC(O)C(CO)(CO)CO PUWSPTQNHGUGDZ-UHFFFAOYSA-N 0.000 description 1
- SZSSMFVYZRQGIM-UHFFFAOYSA-N 2-(hydroxymethyl)-2-propylpropane-1,3-diol Chemical compound CCCC(CO)(CO)CO SZSSMFVYZRQGIM-UHFFFAOYSA-N 0.000 description 1
- FPFSGDXIBUDDKZ-UHFFFAOYSA-N 3-decyl-2-hydroxycyclopent-2-en-1-one Chemical compound CCCCCCCCCCC1=C(O)C(=O)CC1 FPFSGDXIBUDDKZ-UHFFFAOYSA-N 0.000 description 1
- 229910000497 Amalgam Inorganic materials 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- ZMZDMBWJUHKJPS-UHFFFAOYSA-M Thiocyanate anion Chemical compound [S-]C#N ZMZDMBWJUHKJPS-UHFFFAOYSA-M 0.000 description 1
- LCKIEQZJEYYRIY-UHFFFAOYSA-N Titanium ion Chemical compound [Ti+4] LCKIEQZJEYYRIY-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 238000000184 acid digestion Methods 0.000 description 1
- 238000005267 amalgamation Methods 0.000 description 1
- 239000001273 butane Substances 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 239000008396 flotation agent Substances 0.000 description 1
- 125000005456 glyceride group Chemical group 0.000 description 1
- ZMZDMBWJUHKJPS-UHFFFAOYSA-N hydrogen thiocyanate Natural products SC#N ZMZDMBWJUHKJPS-UHFFFAOYSA-N 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000012452 mother liquor Substances 0.000 description 1
- OFBQJSOFQDEBGM-UHFFFAOYSA-N n-pentane Natural products CCCCC OFBQJSOFQDEBGM-UHFFFAOYSA-N 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- ULWHHBHJGPPBCO-UHFFFAOYSA-N propane-1,1-diol Chemical compound CCC(O)O ULWHHBHJGPPBCO-UHFFFAOYSA-N 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 238000005549 size reduction Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- CMWCOKOTCLFJOP-UHFFFAOYSA-N titanium(3+) Chemical compound [Ti+3] CMWCOKOTCLFJOP-UHFFFAOYSA-N 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
- B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
- B02C23/00—Auxiliary methods or auxiliary devices or accessories specially adapted for crushing or disintegrating not provided for in preceding groups or not specially adapted to apparatus covered by a single preceding group
- B02C23/06—Selection or use of additives to aid disintegrating
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B34/00—Obtaining refractory metals
- C22B34/10—Obtaining titanium, zirconium or hafnium
- C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
- C22B34/1204—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 preliminary treatment of ores or scrap to eliminate non- titanium constituents, e.g. iron, without attacking the titanium constituent
Definitions
- This invention relates to a method for improving the grinding of titaniferous ores and increasing the amount of recovery of titanium dioxide from said ores.
- the first step in the sulfuric acid process for recovery of titanium dioxide from titaniferous ores is to grind the ore to a desired particle size.
- the ore is digested with sulfuric acid to yield a digestion cake which consists essentially of water soluble sulfates of titanium and iron, as well as minor impurities.
- the recovery of titanium can be determined by comparing (a) the titanium assay and weight of the ore to (b) the titanium assay and volume of the resulting solution.
- the sulfuric acid process for preparing titanium dioxide from titaniferous ores is conducted on a large scale and thus, even a small increase in the recovery of titanium dioxide can be commercially important. For example, for a 25 ton batch of titaniferous ore containing 64.6% titanium dioxide, a change in the titanium dioxide recovery from 84.5% to 89% represents a 29% decrease in unrecovered, or wasted titanium dioxide, and 1400 pounds extra titanium dioxide actually recovered. So, any increase in the efficiency of comminution of a titaniferous ore will result in a worthwhile saving even though the unit saving may appear small.
- Canadian Patent No. 962,003 discloses the application of propane diol to pigmentary titanium dioxide, following its preparation by either of the well known sulfuric acid or chloride processes, to improve the dispersibility characteristics of the pigment, particularly in paints; and U.S. Patent No. 3,076,719 describes a treatment of similarly produced titanium dioxide pigment with a polyol of from 4 to 10 carbon atoms which prevents clumping during storage.
- U.S. Patent No. 2,822,241 discloses the addition of a glyceride, particularly a monoglyceride, to a titaniferous ore containing organic flotation agents to improve the digestion of the ore in sulfuric acid.
- the present invention provides as a major object a method whereby the comminution of titaniferous ores may be conducted more efficiently, with the use of certain polyols, so that the recovery of titanium dioxide from said ores upon digestion may be enhanced. Further objects and advantages of the invention will become apparent from the description of the invention which ensues.
- the polyols of the present invention have the formula: R ⁇ C ⁇ (-R'OH) wherein R is alkyl (C 1 -C 4 ), or hydroxyalkyi (C 1 -C 4 ) containing up to 3 hydroxy groups, and wherein R' is alkylene (C 1 -C 3 ).
- R is alkyl (C 1 -C 3 ) and R I is methylene.
- R is ethyl and R' is methylene.
- the polyols are preferably stable and wettable in concentrated sulfuric acid at ambient temperatures (25°C. to 35°C.), but tend to be less stable at the digestion reaction temperature.
- Suitable such compounds include trimethylolpropane, I-hydroxy-2, 2-dimethylolpropane; 1-hydroxy-2,2-dimethylolpentane; 1--hydroxy-3,3-diethylolpentane; 1,3-dihydroxy-2,2-diemthylol- butane, and pentaerythritol.
- the polyol is added to the titaniferous ore in an amount effective to improve the comminution thereof. Generally this amount will be from about 0.005% to about 2% by weight of the ore, desirably from about 0.05% to about 1%, and preferably from about 0.07% to about 0.5%. However, more of the polyol may be added if so desired.
- the comminution is rendered more efficient and the ultimate recovery of titanium dioxide from the ore, upon digestion thereof in sulfuric acid, is enhanced.
- the polyol appears to act as an anti-caking agent for the ore during comminution., resulting in a more rapid reduction of ore particle size.
- the smaller particles are believed to be better wetted by the sulfuric acid, thereby yielding a higher recovery of titanium dioxide.
- the continued presence of the polyol in the sulfuric acid digestion medium apparently further augments the recovery of titanium dioxide from the ore.
- TMP trimethylolpropane
- a 1500 g. sample of the ore was first dried at 110°C. to less than 0.2% water and then placed in a gallon ball jar containing 7500 g. of 1 inch steel balls.
- the ball jar was rotated at 53 rpm for the lengths of time shown in Table I below.
- the ball jar was emptied and the ore particle size determined on a 100 g. sample by sifting in a Tyler Ro-Tap through a bank of sieves ranging from 100 to 325 mesh (Tyler - U.S. Standard) for 30 minutes.
- Table 1 demonstrates that for grind times of 30 minutes and 360 minutes, more -325 mesh particles were produced when TMP in an amount of 0.1% was added to the ore. For this procedure, regular commercially used steel balls, which were not polished, were employed.
- This example shows the improvement in titanium dioxide recovery when a titaniferous ore which was ground using a polyol as a grinding aid is digested with sulfuric acid.
- the method used in this example closely approximates the industrial digestion process, so the results received here are representative of results which would be expected on an industrial scale.
- the end liquor contained about 20% sulfuric acid, and a sufficient quantity was added so that after the valences of all other recoverable sulfatable ore components had been satisfied, there remained enough sulfuric acid to satisfy between 65 and 80% of the titanium valences with sulfate ions.
- the samples were digested in the acid solution at temperatures of about 180-190°C. for about 2 1/2 hours. Thereupon, the resulting digestion cakes were dissolved in water to form a titaniferous liqour which was analyzed for titanium dioxide content, and the results compared with the analysis of the original ore, to determine the titanium dioxide recovery.
- the determination of recovery can be made using any well known method, e.g., reduction of the titanium (IV) to titanium (III) with zinc amalgam and titration of the reduced titanium with ferric ammonium sulfate to a thiocyanate end-point.
- Example 1 The procedure of Example 1 is repeated, except that the trimethylolpropane is replaced by an equal weight amount of l-hydroxy-2,2-dimethylolpropane; I-hydroxy-2,2-di--methylolpentane; 1-hydroxy-3,3-diethylolpentane; 1,3-di--hydroxy-2,2-dimethylolbutane, and pentaerythritol.
- Example 1 The procedure of Example 1 is repeated, except that trimethylolpropane in amounts equal to 0.005%, 0.05%, 0.5%, 1% and 2% is added to the ore.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Environmental & Geological Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Food Science & Technology (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE8282100910T DE3271092D1 (en) | 1982-02-09 | 1982-02-09 | Improved grinding of titaniferous ores to enhance recovery of titanium dioxide |
EP19820100910 EP0085728B1 (fr) | 1982-02-09 | 1982-02-09 | Procédé pour le broyage de minerais de titane pour exalter le rendement du dioxyde de titane |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP19820100910 EP0085728B1 (fr) | 1982-02-09 | 1982-02-09 | Procédé pour le broyage de minerais de titane pour exalter le rendement du dioxyde de titane |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0085728A1 true EP0085728A1 (fr) | 1983-08-17 |
EP0085728B1 EP0085728B1 (fr) | 1986-05-14 |
Family
ID=8188863
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19820100910 Expired EP0085728B1 (fr) | 1982-02-09 | 1982-02-09 | Procédé pour le broyage de minerais de titane pour exalter le rendement du dioxyde de titane |
Country Status (2)
Country | Link |
---|---|
EP (1) | EP0085728B1 (fr) |
DE (1) | DE3271092D1 (fr) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0184723A1 (fr) * | 1984-12-04 | 1986-06-18 | Cyanamid Canada Inc. | Méthode de traitement d'agents de désulfuration essentiellement constitués de carbures et prévus pour être injectés dans la fonte |
US5913234A (en) * | 1996-11-05 | 1999-06-15 | Orbisphere Laboratories Neuchatel S.A. | Spectroscopic method and apparatus |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2822241A (en) * | 1953-08-17 | 1958-02-04 | Nat Lead Co | Digestion in sulphuric acid of titaniferous ore concentrates containing organic flotation agent |
US3076719A (en) * | 1960-09-15 | 1963-02-05 | American Cyanamid Co | Titanium dioxide pigment of easier dispersibility |
DE1912845A1 (de) * | 1968-03-14 | 1969-10-16 | Titangmbh | Verfahren und Vorrichtung zur Herstellung von TiO2-Pigment mit verbesserten Pigmenteigenschaften und verbesserter Dispersion |
GB1400067A (en) * | 1971-07-21 | 1975-07-16 | American Cyanamid Co | Tio2 slurries |
-
1982
- 1982-02-09 EP EP19820100910 patent/EP0085728B1/fr not_active Expired
- 1982-02-09 DE DE8282100910T patent/DE3271092D1/de not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2822241A (en) * | 1953-08-17 | 1958-02-04 | Nat Lead Co | Digestion in sulphuric acid of titaniferous ore concentrates containing organic flotation agent |
US3076719A (en) * | 1960-09-15 | 1963-02-05 | American Cyanamid Co | Titanium dioxide pigment of easier dispersibility |
DE1912845A1 (de) * | 1968-03-14 | 1969-10-16 | Titangmbh | Verfahren und Vorrichtung zur Herstellung von TiO2-Pigment mit verbesserten Pigmenteigenschaften und verbesserter Dispersion |
GB1400067A (en) * | 1971-07-21 | 1975-07-16 | American Cyanamid Co | Tio2 slurries |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0184723A1 (fr) * | 1984-12-04 | 1986-06-18 | Cyanamid Canada Inc. | Méthode de traitement d'agents de désulfuration essentiellement constitués de carbures et prévus pour être injectés dans la fonte |
US5913234A (en) * | 1996-11-05 | 1999-06-15 | Orbisphere Laboratories Neuchatel S.A. | Spectroscopic method and apparatus |
Also Published As
Publication number | Publication date |
---|---|
EP0085728B1 (fr) | 1986-05-14 |
DE3271092D1 (en) | 1986-06-19 |
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