CN102757091A - Method for preparing high-concentration titanic liquid - Google Patents
Method for preparing high-concentration titanic liquid Download PDFInfo
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- CN102757091A CN102757091A CN2011101093442A CN201110109344A CN102757091A CN 102757091 A CN102757091 A CN 102757091A CN 2011101093442 A CN2011101093442 A CN 2011101093442A CN 201110109344 A CN201110109344 A CN 201110109344A CN 102757091 A CN102757091 A CN 102757091A
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Abstract
The invention belongs to the field of treating inorganic compounds, and particularly relates to a method for preparing high-concentration titanic liquid from a solid intermediate product in titanium dioxide clean preparation technology by an alkaline molten salt method at one step. The amorphous solid intermediate product in the titanium dioxide clean preparation process by the alkaline molten salt method is used as a raw material, low-concentration sulfuric acid is adopted, and the high-concentration clear titanic liquid (with the concentration ranging from 220g/L to 300g/L measured by TiO2) is prepared under the condition of low-temperature acid hydrolysis at one step. Compared with the traditional titanium dioxide preparation technology by a sulfuric acid method, the method has the advantages that steps such as vacuum concentration can be omitted, and the concentration of the prepared titanic liquid is higher than that of titanium liquid prepared after a vacuum concentration step in the traditional sulfuric acid method; and titanium dioxide preparation processes are simplified, equipment investment is reduced, energy consumption is lowered, and productivity and product quality are improved.
Description
Technical field
The invention belongs to the mineral compound manufacture field, specially refer to a kind of method for preparing high density titanium liquid by the step of the solid intermediate product (titanium-containing compound) in the alkali molten-salt growth method titanium white clearer production technology.
Background technology
Titanium oxide is commonly called as white titanium pigment, is a kind of important source material in the chemical industry, and is nontoxic, be harmless to the health, and it is most important white pigment, accounts for 80% of whole white pigment usage quantitys, consumes 90% titanium resource in the world, is the third-largest inorganic chemical product.Industrial process comprises sulfuric acid process and chlorination, and the manufacturing enterprise of China 95% adopts sulfuric acid process, and this technical process is long, pollution is heavy, reaction medium can't economic recycle.
In recent years; Chinese Academy Of Sciences Process Engineering Research Institute has invented and has utilized sodium hydroxide, Pottasium Hydroxide fused salt to decompose the clearer production technology (ZL 200610114130.3, ZL200610114131.8) that titanium resource prepares titanium oxide; This technology has that mineral efficiently decompose, the advantage of the economic recycle of medium, polycomponent comprehensive utilization, and more traditional sulfuric acid process has tangible environmental benefit.But; The preparation process of titanium liquid and the character of gained titanium liquid are not further disclosed in the patent (ZL200610114130.3, ZL 200610114131.8); And titanium liquid prepares process and titanium fluidity matter is one of core process of clearer production technology, is related to whether can prepare the titanium oxide with excellent pigment performance.
Summary of the invention
The objective of the invention is to titanium liquid in traditional sulfuric acid process prepare that process complicacy, energy consumption are high, medium can't economic round-robin problem; Proposing a kind of is raw material with the unbodied solid intermediate product (titanium-containing compound) in the alkali molten-salt growth method titanium white clearer production technology; Adopt low-concentration sulfuric acid, next step prepares the method for high density clarification titanium liquid in the low temperature acidolysis.
The present invention is to be raw material with the solid intermediate product (titaniferous compound) that relates in the alkali molten-salt growth method titanium white clearer production technology; Adopt low-concentration sulfuric acid; Next step makes high density titanium liquid in the low temperature acidolysis; This titanium liquid can make the uniform metatitanic acid of size distribution through hydrolysis, and metatitanic acid can be produced the excellent white titanium pigment of pigment performance through calcining, coating.
In the tradition sulfate process titanium dioxide production technique, the raw material of acidolysis is ilmenite, ilmenite concentrate or the titanium slag of crystalline state, uses vitriolic mass concentration＞85%, 180～200 ℃ of acidolysis temperatures, and making the titanium concentration scope is that 130～150g/L is (with TiO
2Meter), need vacuum concentration to 190～200g/L (with TiO
2Meter) hydrolysis again.Compare with acidolysis process in the sulfuric acid process, characteristics of the present invention are for the solid intermediate product that adopts amorphous state is a raw material, the use sulfuric acid concentration is low, acidolysis temperature is low, and the titanium liquid that makes need not to concentrate and can reach 220g/L (with TiO
2Meter) more than.Because the sulfuric acid working concentration is low, the mother liquor after the hydrolysis is a reusable edible through preliminary concentrating.
The present invention is to be raw material with the solid intermediate product in the alkali molten-salt growth method titanium white clearer production technology, through low-concentration sulfuric acid, under the low temperature acidolysis, makes thick titanium liquid, and thick titanium liquid obtains high density clarification titanium liquid through flocculation, sedimentation, filtration.Method of the present invention may further comprise the steps:
(1) be that 45%～70% dilute sulphuric acid mixes with solid intermediate product (titanium-containing compound) in the alkali molten-salt growth method titanium white clearer production technology and mass concentration; In temperature is that 30～80 ℃ of following insulated and stirred are carried out acidolysis (time of preferable acidolysis is 1～72 hour; Further the time of preferable acidolysis is 3～72 hours); Leave standstill (time of preferably leaving standstill is 1～24 hour), supernatant is the thick titanium liquid that contains suspended solid;
(2) in the thick titanium liquid that step (1) obtains, add modified polyacrylamide (AMPAM) as flocculation agent; In temperature is 60～70 ℃ of following insulated and stirred (time of preferable stirring is 3～6 hours); Through flocculation, sedimentation, filtration, can obtain concentration is that 220～300g/L is (with TiO
2Meter) clarification titanium liquid.
The solid-liquid mass ratio of described solid intermediate product and described dilute sulphuric acid is 1: 1～1.5: 1.
The crystal formation of described solid intermediate product is an amorphous state, and the wet basis titanium content is 25%～40% (with TiO
2Meter).
Described solid intermediate product is the solid intermediate product described in ZL 200610114130.3 and the ZL 200610114131.8; It is that titanium slag and sodium hydroxide are mixed; Obtain after washing (the solid-liquid mass ratio of solid-state intermediate product and water be preferably 1: 3～1: 100) at the solid-state intermediate products that obtain after 350 ℃～550 ℃ down reactions (the general reaction times is 0.2～5 hour), wherein the mass ratio of sodium hydroxide and titanium slag is 0.8: 1～3: 1; Or
Titanium slag and Pottasium Hydroxide are mixed; After washing (the solid-liquid mass ratio of solid-state intermediate product and water be preferably 1: 3～1: 100), obtain obtaining solid-state intermediate product after 380 ℃～500 ℃ down reactions (the general reaction times is 0.2～3 hour), wherein the mass ratio of Pottasium Hydroxide and titanium slag is 0.5: 1～2: 1.
Describedly in the thick titanium liquid that step (1) obtains, add modified polyacrylamide, the volume of the modified polyacrylamide that is added be thick titanium liquid long-pending 3%～10%, the mass concentration of modified polyacrylamide is 0.1%～1%.
The mass content of titanium oxide is greater than 85% in the described titanium slag.
The staple of described clarification titanium liquid is sulfuric acid, titanium sulfate and titanyl sulfate; The effective acid concentration of described clarification titanium liquid is that 300～600g/L is (with H
2SO
4Meter).
The more traditional sulfate process titanium dioxide production technology of the present invention can be saved steps such as vacuum concentration, and the titanium concentration that obtains is higher than the titanium concentration behind the vacuum concentration; Simplified the Producing Titanium Dioxide flow process; Reduce the equipment input, reduced energy consumption, improved production capacity and quality product.
The present invention compares with traditional sulfuric acid process acidolysis process, and the present invention has following advantage: (1) acidolysis is low with sulfuric acid concentration, and mother liquor behind the titanium hydrolysis can economic recycle through preliminary concentrating, and reduces acid consumption and spent acid quantity discharged; (2) acidolysis temperature is low, and is easy to operate, energy consumption is low, and is low for equipment requirements; (3) titanium concentration that makes is high, can increase substantially production capacity and product pigment performance.
Embodiment
Embodiment 1
Utilize the method among ZL 200610114130.3 and the ZL 200610114131.8 to prepare solid intermediate product (titanium-containing compound); The mass content of titanium oxide is mixed greater than 85% titanium slag and sodium hydroxide; Reacted 0.2～5 hour down at 350 ℃～550 ℃; Wherein the mass ratio of sodium hydroxide and titanium slag is 0.8: 1～3: 1; Solid-state intermediate product that obtains and water are to wash in 1: 3～1: 100 with the solid-liquid mass ratio, make the solid intermediate product after the washing; Or
The mass content of titanium oxide is mixed greater than 85% titanium slag and Pottasium Hydroxide; Reacted 0.2～3 hour down at 380 ℃～500 ℃; Wherein the mass ratio of Pottasium Hydroxide and titanium slag is 0.5: 1～2: 1; Solid-state intermediate product that obtains and water are to wash in 1: 3～1: 100 with the solid-liquid mass ratio, make the solid intermediate product after the washing.
(the wet basis titanium content is 32%, with TiO to get crystal formation that the 180g method for preparing obtains and be the solid intermediate product of amorphous state
2Meter) be that 60% sulphuric acid soln mixes with the 100mL mass concentration; The solid-liquid mass ratio of solid intermediate product and dilute sulphuric acid is 1.2: 1, is 50 ℃ of following insulated and stirred 8 hours in temperature, leaves standstill 4 hours; Taking-up contains the supernatant of trace suspension thing, obtains the thick titanium liquid of 200mL; Adding 10mL mass concentration is 0.1% AMPAM flocculation agent in the thick titanium liquid of the 200mL that obtains, and is 60 ℃ of following insulated and stirred 4 hours in temperature, and through flocculation, sedimentation, filtration, the staple of analyzing gained clarification titanium liquid is sulfuric acid, titanium sulfate and titanyl sulfate; The effective acid concentration of described clarification titanium liquid is that 400～420g/L is (with H
2SO
4Meter), the concentration of titanium oxide is that 235～240g/L is (with TiO
2Meter).
Embodiment 2
With reference to embodiment 1 preparation solid intermediate product (titanium-containing compound); (the wet basis titanium content is 40%, with TiO to get crystal formation that 200g prepares and be the solid intermediate product of amorphous state
2Meter) be that 70% sulphuric acid soln mixes with the 100mL mass concentration; The solid-liquid mass ratio of solid intermediate product and dilute sulphuric acid is 1.2: 1, is 30 ℃ of following insulated and stirred 4 hours in temperature, leaves standstill 12 hours; Taking-up contains the supernatant of trace suspension thing, obtains the thick titanium liquid of 200mL; Adding 6mL mass concentration is 1% AMPAM flocculation agent in the thick titanium liquid that obtains, and is 65 ℃ of following insulated and stirred 6 hours in temperature, and through flocculation, sedimentation, filtration, the staple of analyzing gained clarification titanium liquid is sulfuric acid, titanium sulfate and titanyl sulfate; The effective acid concentration of described clarification titanium liquid is that 580～600g/L is (with H
2SO
4Meter), the concentration of titanium oxide is that 290～300g/L is (with TiO
2Meter).
Embodiment 3
With reference to embodiment 1 preparation solid intermediate product (titanium-containing compound); (the wet basis titanium content is 25%, with TiO to get crystal formation that 160g prepares and be the solid intermediate product of amorphous state
2Meter) be that 50% sulphuric acid soln mixes with the 100mL mass concentration; The solid-liquid mass ratio of solid intermediate product and dilute sulphuric acid is 1.1: 1, is 60 ℃ of following insulated and stirred 72 hours in temperature, leaves standstill 1 hour; Taking-up contains the supernatant of trace suspension thing, obtains the thick titanium liquid of 150mL; Adding 15mL mass concentration is 0.5% AMPAM flocculation agent in the thick titanium liquid that obtains, and is 70 ℃ of following insulated and stirred 3 hours in temperature, and through flocculation, sedimentation, filtration, the staple of analyzing gained clarification titanium liquid is sulfuric acid, titanium sulfate and titanyl sulfate; The effective acid concentration of described clarification titanium liquid is that 300～320g/L is (with H
2SO
4Meter), the concentration of titanium oxide is that 220～225g/L is (with TiO
2Meter).
Embodiment 4
With reference to embodiment 1 preparation solid intermediate product (titanium-containing compound); (the wet basis titanium content is 38%, with TiO to get crystal formation that 160g prepares and be the solid intermediate product of amorphous state
2Meter) be that 70% sulphuric acid soln mixes with the 100mL mass concentration; The solid-liquid mass ratio of solid intermediate product and dilute sulphuric acid is 1.0: 1, is 40 ℃ of following insulated and stirred 24 hours in temperature, leaves standstill 3 hours; Taking-up contains the supernatant of trace suspension thing, obtains the thick titanium liquid of 160mL; Adding 8mL mass concentration is 1% AMPAM flocculation agent in the thick titanium liquid that obtains, and is 65 ℃ of following insulated and stirred 3 hours in temperature, and through flocculation, sedimentation, filtration, the staple of analyzing gained clarification titanium liquid is sulfuric acid, titanium sulfate and titanyl sulfate; The effective acid concentration of described clarification titanium liquid is that 520～540g/L is (with H
2SO
4Meter), the concentration of titanium oxide is that 240～245g/L is (with TiO
2Meter).
Embodiment 5
With reference to embodiment 1 preparation solid intermediate product (titanium-containing compound); (the wet basis titanium content is 30%, with TiO to get crystal formation that 200g prepares and be the solid intermediate product of amorphous state
2Meter) be that 45% sulphuric acid soln mixes with the 100mL mass concentration; The solid-liquid mass ratio of solid intermediate product and dilute sulphuric acid is 1.5: 1, is 40 ℃ of following insulated and stirred 6 hours in temperature, leaves standstill 24 hours; Taking-up contains the supernatant of trace suspension thing, obtains the thick titanium liquid of 200mL; Adding 10mL mass concentration is 0.8% AMPAM flocculation agent in the thick titanium liquid that obtains, and is 65 ℃ of following insulated and stirred 6 hours in temperature, and through flocculation, sedimentation, filtration, the staple of analyzing gained clarification titanium liquid is sulfuric acid, titanium sulfate and titanyl sulfate; The effective acid concentration of described clarification titanium liquid is that 320～340g/L is (with H
2SO
4Meter), the concentration of titanium oxide is that 235～240g/L is (with TiO
2Meter).
Claims (10)
1. the preparation method of a high density titanium liquid, it is characterized in that: described method may further comprise the steps:
(1) being that 45%～70% dilute sulphuric acid mixes with solid intermediate product in the alkali molten-salt growth method titanium white clearer production technology and mass concentration, is that 30～80 ℃ of following insulated and stirred are carried out acidolysis in temperature, leaves standstill, and supernatant is the thick titanium liquid that contains suspended solid;
(2) in the thick titanium liquid that step (1) obtains, add modified polyacrylamide, insulation is stirred under temperature is 60～70 ℃, and through flocculation, sedimentation, filtration, obtaining concentration is that 220～300g/L is (with TiO
2Meter) clarification titanium liquid;
Described solid intermediate product is that titanium slag and sodium hydroxide are mixed, and obtains after washing at 350 ℃～550 ℃ solid-state intermediate products that obtain after reacting down, and wherein the mass ratio of sodium hydroxide and titanium slag is 0.8: 1～3: 1; Or
Titanium slag and Pottasium Hydroxide are mixed, after reacting under 380 ℃～500 ℃, obtain solid-state intermediate product and after washing, obtain, wherein the mass ratio of Pottasium Hydroxide and titanium slag is 0.5: 1～2: 1.
2. method according to claim 1 is characterized in that: the time of described acidolysis is 1～72 hour.
3. method according to claim 2 is characterized in that: the time of described acidolysis is 3～72 hours.
4. method according to claim 1 is characterized in that: the described time of leaving standstill is 1～24 hour.
5. method according to claim 1 is characterized in that: the time of the described stirring of step (2) is 3～6 hours.
6. method according to claim 1 is characterized in that: the solid-liquid mass ratio of described solid intermediate product and described dilute sulphuric acid is 1: 1～1.5: 1.
7. according to claim 1 or 6 described methods, it is characterized in that: the crystal formation of described solid intermediate product is an amorphous state, and the wet basis titanium content is 25%～40% (with TiO
2Meter).
8. method according to claim 1; It is characterized in that: describedly in the thick titanium liquid that step (1) obtains, add modified polyacrylamide; The volume of the modified polyacrylamide that is added be thick titanium liquid long-pending 3%～10%, the mass concentration of modified polyacrylamide is 0.1%～1%.
9. method according to claim 1 is characterized in that: the mass content of titanium oxide is greater than 85% in the described titanium slag.
10. method according to claim 1 is characterized in that: the staple of described clarification titanium liquid is sulfuric acid, titanium sulfate and titanyl sulfate; The effective acid concentration of described clarification titanium liquid is that 300～600g/L is (with H
2SO
4Meter).
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| CN103553126A (en) * | 2013-11-07 | 2014-02-05 | 天津致远投资集团有限公司 | Method for preparing titanium dioxide by utilizing low-concentration alkaline liquor |
| CN109354060A (en) * | 2018-08-20 | 2019-02-19 | 江苏钛谷科技有限公司 | A kind of technique of clean manufacturing titanium dioxide |
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2011
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Cited By (2)
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| CN103553126A (en) * | 2013-11-07 | 2014-02-05 | 天津致远投资集团有限公司 | Method for preparing titanium dioxide by utilizing low-concentration alkaline liquor |
| CN109354060A (en) * | 2018-08-20 | 2019-02-19 | 江苏钛谷科技有限公司 | A kind of technique of clean manufacturing titanium dioxide |
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| CN102757091B (en) | 2014-07-30 |
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