CN110028046A - The method of ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process - Google Patents
The method of ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process Download PDFInfo
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- CN110028046A CN110028046A CN201910411327.0A CN201910411327A CN110028046A CN 110028046 A CN110028046 A CN 110028046A CN 201910411327 A CN201910411327 A CN 201910411327A CN 110028046 A CN110028046 A CN 110028046A
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- ferrous sulfate
- acid
- sulfuric acid
- titanium dioxide
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- C01B17/00—Sulfur; Compounds thereof
- C01B17/69—Sulfur trioxide; Sulfuric acid
- C01B17/88—Concentration of sulfuric acid
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Abstract
The invention belongs to titanium dioxide technical fields, and in particular to a kind of method of ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process.Technical problem to be solved by the invention is to provide the methods of ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, the following steps are included: two-step method: step 1: ferrous sulfate monohydrate and spent acid are mixed, it places, separation of solid and liquid obtains solution, and h 2 so 4 concentration is 35~38% in solution；Step 2: anhydrous slufuric acid ferrous iron and first step solution are mixed, place, separation of solid and liquid obtains solution, and h 2 so 4 concentration is 50~55% in solution；Or one-step method: anhydrous slufuric acid ferrous iron and spent acid are mixed, and are placed, and separation of solid and liquid obtains solution, and h 2 so 4 concentration is 50~55% in solution.Waste acid treatment method provided by the invention not only efficiently utilizes scrap feed material caused by Producing Titanium Dioxide, but also can reduce the pressure caused by environment, improves operating environment, great prospects for commercial application.
Description
Technical field
The invention belongs to titanium dioxide technical fields, and in particular to a kind of side of ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process
Method.
Background technique
Titanium dioxide is a kind of excellent white pigment, is widely used in paint, coating, papermaking, plastics and electric welding at present
The industries such as item.
Currently, the technique of production titanium dioxide mainly has sulfuric acid process and chloridising, two kinds of techniques are simultaneously deposited, and production capacity and yield
It is very huge.However both production technologies all have certain environmental pressure, and for Production By Sulfuric Acid Process technique, production
Green vitriol (FeSO by a large amount of hydrolysis spent acid is generated and containing seven crystallizations water in the process4·7H2O).When (main with ilmenite concentrate
Wanting ingredient is metatitanic acid iron FeTiO3, wherein content of titanium dioxide is 45~50 weight %) and when being raw material, generally produce 1 ton of titanium
3.5~4 ton of seven inkstone of output is generated 7~8 tons of hydrolysis spent acid containing about 20% sulfuric acid by white powder.
There is processing difficulty in view of a large amount of green vitriols in European countries, therefore turn to chloridising production to avoid.This
Outside, high titanium slag is used to carry out Production By Sulfuric Acid Process for raw material, though the problem of can avoid green vitriol, the utilization of hydrolysis Waste Sulfuric Acid is still
In the presence of.
Due to too big using the waste sulfuric acid solution quantum of output of method for producing gtitanium dioxide with sulphuric acid by-product, and contain a certain amount of sulphur
It is sour ferrous, so that this waste sulfuric acid solution can not be utilized in other fields using dilute sulfuric acid.Currently, generalling use lime
This waste sulfuric acid solution is handled with the method that generates calcium sulfate in stone, so obtained from calcium sulfate there is no a utility value and
It can only store up, this does not utilize raw material not only well, but also biggish pressure can be caused to environment.
Positive method is when first passing through preliminary evaporation and concentration to improve the concentration of sulfuric acid to 30%~40%, to isolate
Ferrous sulfate；Further evaporation and concentration becomes 60% or more sulfuric acid, returns to acidolysis operation, uses for interruption acidolysis, thus
Completely utilized.But the corrosivity of sulfuric acid solution at high temperature is extremely strong, it is desirable that is worth higher graphite material, steams simultaneously
Hair concentration needs the steam boiler of large capacity, so that the equipment investment of this method is high and production cost is also high.From each factory
From the point of view of the application effect of family, the processing cost that the sulfuric acid concentration in spent acid doubles is about 1000 yuan/t, gelled acid per ton
Cost is even than (500~800 yuan/t98%H of fresh sulfuric acid2SO4) also want it is expensive very much, lead to the middle-size and small-size sulfuric acid of most domestic
Method titanium powder plant is not dared to inquire, and lime neutralisation is all made of.Moreover, the graphite heater in the presence of evaporating concentration process blocks
Problem could not also be completely resolved so far.
Summary of the invention
The present invention in order to overcome existing method processing method for producing gtitanium dioxide with sulphuric acid by-product waste sulfuric acid solution existing at least
One technical problem, and provide a kind of method of ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process.
The method of ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process of the present invention, two-step method or one-step method, comprising the following steps:
Two-step method:
Step 1: ferrous sulfate monohydrate and spent acid are mixed, place, separation of solid and liquid obtains solution, sulfuric acid quality in solution
Concentration is 35~38%；
Step 2: anhydrous slufuric acid ferrous iron and first step solution are mixed, place, separation of solid and liquid obtains solution, sulphur in solution
Sour mass concentration is 50~55%；
One-step method:
Anhydrous slufuric acid ferrous iron and spent acid are mixed, placed, separation of solid and liquid obtains solution, and h 2 so 4 concentration is 50 in solution
~55%.
Specifically, the spent acid is that sulfuric acid process prepares titanium in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process
The waste sulfuric acid solution of white powder by-product.
Further, in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, in the spent acid containing sulfuric acid and
Ferrous sulfate.
Further, in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, sulfuric acid quality in the spent acid
Concentration is 17~20%, and ferrous sulfate mass concentration is 2~3%.
Specifically, in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, the first step in two-step method, every 100 weight
Measure part spent acid 60~65 parts by weight ferrous sulfate monohydrates of corresponding addition.
Specifically, in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, second step in two-step method, every 100 weight
It is ferrous to measure corresponding 600~610 parts by weight anhydrous slufuric acids of addition of part first step solution.
Specifically, in one-step method, every 100 parts by weight are useless in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process
Acid is corresponding to be added 510~520 parts by weight anhydrous slufuric acids ferrous irons.
Preferably, described to put in two-step method or one-step method in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process
Setting temperature is room temperature.Standing time is 4~8h.
Specifically, in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, in two-step method, the one water sulphur of raw material
The sour ferrous green vitriol by method for producing gtitanium dioxide with sulphuric acid by-product is dry to be obtained except the crystallization water.Further, the drying is 70
~100 DEG C of dryings.
Specifically, in two-step method, the first step is separated by solid-liquid separation in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process
Obtained solid is ferrous sulfate heptahydrate.Further, it returns and uses after 6 crystallizations water of the dry removing of gained ferrous sulfate heptahydrate.
Further, the drying is in 70~100 DEG C of drying and dehydratings.
Specifically, in two-step method, second step is separated by solid-liquid separation in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process
Obtained solid is ferrous sulfate monohydrate.Further, it returns and uses after 1 crystallization water of the dry removing of gained ferrous sulfate monohydrate.
Further, the drying is in 300~350 DEG C of drying and dehydratings.
Specifically, in one-step method, it is solid to be separated by solid-liquid separation gained in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process
Body is ferrous sulfate monohydrate.Further, it returns and uses after 1 crystallization water of the dry removing of gained ferrous sulfate monohydrate.More into one
Step, the drying is in 300~350 DEG C of drying and dehydratings.
Specifically, in the method for above-mentioned ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, gained h 2 so 4 concentration is 50~
55% solution directly returns to hydrolysis procedure and uses for continuous acidolysis or be further concentrated to 60% or more and return again to hydrolysis procedure
It is used for interruption acidolysis.
Method provided by the invention using ferrous sulfate concentration waste sulfuric acid solution, it is entirely avoided boiler and evaporator
Use, avoid the use of expensive resistant material, to reduce fixed investment, and the operation of every step at normal temperature into
Row, significantly improves operating condition in this way, but also the economy of Waste Sulfuric Acid concentration is improved.The method of the present invention not only has
Useless raw material is utilized to effect, but also can reduce the pressure caused by environment, improves operating environment, before great industrial application
Scape.
Specific embodiment
The method of ferrous sulfate concentrated vitriol method titanium white waste acid, comprising the following steps:
Step 1: ferrous sulfate monohydrate (FeSO4·H2O it) is added in Waste Sulfuric Acid and mixes and keep certain time, at this moment institute
The concentration for stating sulfuric acid in Waste Sulfuric Acid reaches 35~38 weight %, is then separated by solid-liquid separation the waste sulfuric acid solution, solid phase is
Ferrous sulfate heptahydrate (FeSO4·7H2O), use is returned after being removed 6 crystallizations water；
Step 2: anhydrous slufuric acid ferrous iron (FeSO is added in the liquid phase that the first step obtains4) mix and keep certain time, this
The concentration of sulfuric acid reaches 50~55 weight % in Shi Suoshu Waste Sulfuric Acid, is then separated by solid-liquid separation the waste sulfuric acid solution, Gu
It is mutually ferrous sulfate monohydrate (FeSO4·H2O), use is returned to after being removed 1 crystallization water, liquid phase returns to acidolysis for continuous acid
Solution uses.
The method of ferrous sulfate concentrated vitriol method titanium white waste acid, comprising the following steps:
By anhydrous slufuric acid ferrous iron (FeSO4) be added in Waste Sulfuric Acid and mix and keep certain time, the at this moment Waste Sulfuric Acid
The concentration of middle sulfuric acid reaches 50~55 weight %, is then separated by solid-liquid separation the waste sulfuric acid solution, and solid phase is sulfuric acid monohydrate
Ferrous iron (FeSO4·H2O), use is returned to after being removed 1 crystallization water, liquid phase returns to acidolysis and uses for continuous acidolysis.
Above-mentioned ferrous sulfate heptahydrate (FeSO4·7H2O the crystallization water of 6 molecules of removing) is dried at 70~100 DEG C, becomes
Ferrous sulfate monohydrate, which returns, to be used.
Above-mentioned ferrous sulfate monohydrate (FeSO4·H2O the crystallization water of 1 molecule of removing) is dried at 300~350 DEG C, becomes
Anhydrous slufuric acid ferrous iron, which returns, to be used.
In the method for the present invention, 50~55% solution of gained h 2 so 4 concentration can return to acidolysis and use for continuous acidolysis；?
It can be concentrated to 60% or more with flue gas, return again to acidolysis and used for interruption acidolysis.
In the method for the present invention, when sulfuric acid concentration reaches 35~38% or more in waste sulfuric acid solution, the sulfuric acid in solution is sub-
Iron forms crystallization water form, is present in solid by being separated by solid-liquid separation then to separate, gained sulphur last in the process of the present invention
Ferrous sulfate amount is few in acid solution, does not influence the subsequent return hydrolysis procedure of acid solution and continues to use；And due to this in spent acid
There are ferrous sulfate for body, can be absorbed water using the part of sulfuric acid ferrous iron, it is possible to reduce the additional amount of ferrous sulfate.
In the method for the present invention, due to becoming a water object from the dehydration of seven water objects, temperature > 65 DEG C are only needed just when dry, temperature
Degree is high, then the drying and dehydrating time is with regard to shorter；And the last one crystallization water is removed from a water object is dry, > 300 are then needed when dry
℃.So the method for the present invention makes full use of the characteristics of anhydride, a water object and seven water objects, two steps are designed using suitable raw material
Method or one-step method dehydration, so as to reach dehydration and concentration purpose on the basis of using more low energy consumption.
In the method for the present invention, ferrous sulfate monohydrate can only take water by force from the solution below of h 2 so 4 concentration 35~38%,
So in spent acid to be processed when using ferrous sulfate monohydrate as raw material h 2 so 4 concentration should 35~38% hereinafter, and
Solution can only be also concentrated to h 2 so 4 concentration 35~38%；When anhydrous slufuric acid ferrous iron takes water by force, when sulfuric acid quality is dense in product
When degree is lower than 35%, then ferrous sulfate heptahydrate can be generated, when h 2 so 4 concentration is 35~55% in product, can be only generated one
Aqueous ferrous sulfate cannot then take water by force when sulfuric acid concentration is more than 55% in product.
Embodiment 1
100 grams of sulfate process titanium dioxides are hydrolyzed into spent acid, wherein the ferrous sulfate containing 20% sulfuric acid and 2~3%.
Step 1: 100 grams of spent acid mix at normal temperature with 62 grams of ferrous sulfate monohydrates, keep after a certain period of time, solid-liquid point
From 57 grams of liquid phases are obtained, sulfuric acid concentration is increased to 35%；About 106 grams of solid phases are obtained, which is ferrous sulfate heptahydrate
(FeSO4·7H2O), after 70 DEG C~100 DEG C dry removings, 6 crystallizations water, return and use；
Step 2: 344 grams of anhydrous slufuric acid ferrous irons are added in 57 grams of liquid phases obtained by the first step, mixed under room temperature, keeps certain
After time, separation of solid and liquid obtains 36.4 grams of liquid phases, and sulfuric acid concentration is increased to 55%；About 385 grams of solid phases are obtained, which is a water
Ferrous sulfate (FeSO4·H2O), after 300 DEG C~350 DEG C dry removing crystallizations water, return and use.
The liquid phase for the h 2 so 4 concentration 55% that second step obtains can return to acidolysis and use for continuous acidolysis；Or use cigarette
Road gas returns after being concentrated to greater than 60% to be used for interruption acidolysis.
Embodiment 2
100 grams of sulfate process titanium dioxides are hydrolyzed into spent acid, wherein containing 20% sulfuric acid and 2~3% ferrous sulfate, with 510 grams
Anhydrous slufuric acid ferrous iron mixes at normal temperature, keeps after a certain period of time, separation of solid and liquid obtains 36.4 grams of liquid phases, and sulfuric acid concentration is increased to
55%；About 571 grams of solid phases are obtained, which is ferrous sulfate monohydrate (FeSO4H2O), in 300 DEG C~350 DEG C dry removings
After the crystallization water, returns and use.
The liquid phase of the h 2 so 4 concentration 55% of acquisition can return to acidolysis and use for continuous acidolysis；Or it is dense with flue gas
It is reduced to after being greater than 60% to return and be used for interruption acidolysis.
Claims (10)
1. the method for ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, it is characterised in that: the following steps are included: two-step method or a step
Method:
Two-step method:
Step 1: ferrous sulfate monohydrate and spent acid are mixed, place, separation of solid and liquid obtains solution, h 2 so 4 concentration in solution
It is 35~38%；
Step 2: anhydrous slufuric acid ferrous iron and first step solution are mixed, place, separation of solid and liquid obtains solution, sulfuric acid matter in solution
Measuring concentration is 50~55%；
One-step method:
Anhydrous slufuric acid ferrous iron and spent acid are mixed, placed, separation of solid and liquid obtains solution, in solution h 2 so 4 concentration be 50~
55%.
2. the method for ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process according to claim 1, it is characterised in that: the spent acid
For the waste sulfuric acid solution of method for producing gtitanium dioxide with sulphuric acid by-product；Further, sulfuric acid and ferrous sulfate are contained in the spent acid；More into
One step, h 2 so 4 concentration is 17~20% in the spent acid, and ferrous sulfate mass concentration is 2~3%.
3. the method for ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process according to claim 1 or 2, it is characterised in that: two steps
The first step in method, every 100 parts by weight spent acid is corresponding to be added 60~65 parts by weight ferrous sulfate monohydrates.
4. the method for described in any item ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, feature exist according to claim 1~3
In: second step in two-step method, every 100 parts by weight first step solution is corresponding to be added 600~610 parts by weight anhydrous slufuric acids ferrous irons.
5. the method for ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process according to claim 1 or 2, it is characterised in that: a step
In method, every 100 parts by weight spent acid is corresponding to be added 510~520 parts by weight anhydrous slufuric acids ferrous irons.
6. the method for described in any item ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, feature exist according to claim 1~5
In: in two-step method or one-step method, the placement temperature is room temperature；Standing time is 4~8h.
7. the method for described in any item ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, feature exist according to claim 1~6
In: in two-step method, the raw material ferrous sulfate monohydrate is obtained by the green vitriol drying of method for producing gtitanium dioxide with sulphuric acid by-product except the crystallization water；
Further, the drying is in 70~100 DEG C of dryings.
8. the method for described in any item ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, feature exist according to claim 1~7
In: in two-step method, it is ferrous sulfate heptahydrate that the first step, which is separated by solid-liquid separation obtained solid,；Further, gained ferrous sulfate heptahydrate is dry
It returns and uses after 6 crystallizations water of dry removing；Further, the drying is 70~100 DEG C of drying and dehydratings.
9. the method for described in any item ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, feature exist according to claim 1~8
In: in two-step method in second step or one-step method, separation of solid and liquid obtained solid is ferrous sulfate monohydrate；Further, gained one
It returns and uses after aqueous ferrous sulfate 1 crystallization water of dry removing；Further, the drying is 300~350 DEG C dry de-
Water.
10. the method for described in any item ferrous sulfate processing titanium dioxide waste acid by sulfuric acid process, feature exist according to claim 1~9
In: gained h 2 so 4 concentration be 50~55% solution directly returns for continuous acidolysis use or be further concentrated to 60% with
On return again to for interruption acidolysis use.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114053759A (en) * | 2020-07-29 | 2022-02-18 | 北京紫光英力化工技术有限公司 | New process for adding salt and dehydrating water-containing organic matter |
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2019
- 2019-05-17 CN CN201910411327.0A patent/CN110028046A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114053759A (en) * | 2020-07-29 | 2022-02-18 | 北京紫光英力化工技术有限公司 | New process for adding salt and dehydrating water-containing organic matter |
| CN114053759B (en) * | 2020-07-29 | 2023-05-05 | 北京紫光英力化工技术有限公司 | New process for salt-adding and dehydration of water-containing organic matter |
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