CN108793252A - A kind of method of content of 6-valence Cr ions in reduction chrome oxide green - Google Patents
A kind of method of content of 6-valence Cr ions in reduction chrome oxide green Download PDFInfo
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- CN108793252A CN108793252A CN201710285612.3A CN201710285612A CN108793252A CN 108793252 A CN108793252 A CN 108793252A CN 201710285612 A CN201710285612 A CN 201710285612A CN 108793252 A CN108793252 A CN 108793252A
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Abstract
The present invention provides it is a kind of reduction chrome oxide green in content of 6-valence Cr ions method, the method includes：Reducing agent is added in the chrome oxide green that drop temperature is 60-400 DEG C into production process, obtains chrome oxide green product.The method can reduce the Cr VI in chrome oxide green so that the water solubles content of chrome oxide green product reduces, and solves the problems, such as that product colour turns to be yellow, and improve the rate of recovery of crome metal；In addition, the method is easy to operate, reducing agent dosage is few, is added in temperature-fall period, is not had an impact to original technique, and reducing agent volatilizees decomposition in reduction process, will not be impacted to chrome oxide green purity.
Description
Technical field
The invention belongs to chromium salt production technical fields, are related to a kind of method reducing content of 6-valence Cr ions in chrome oxide green.
Background technology
Cr VI in chrome oxide green not only increases water solubles content, but also product colour is made to turn to be yellow, and has to product use
Large effect.The method for reducing content of 6-valence Cr ions in chrome oxide green at present mainly has：
(1) chromic anhybride roasts after being mixed into a small amount of boric acid, or adds a small amount of boric acid to reburn chromyl chrome green；
(2) chrome oxide green that chromic anhybride thermally decomposes to yield is hot filling into container closure cooling, and urea is contained in advance in container；(3) it aoxidizes
Chrome green washing detaches liquid phase to moisture percentage 30%-35% except after the hydrotrope, being suspended in the urea liquid of 8%-10%, then
200-280 DEG C of heat treatment；(4) chrome green that chromic anhybride thermally decomposes to yield is crushed with a small amount of ethyl alcohol in vibromill.
Although above method can reduce content of 6-valence Cr ions in chrome oxide green, there is complicated for operation, additive amounts
Greatly, the problems such as increasing production cost.
CN1459419A discloses a kind of method of producing dichromium trioxide using chromic acid thermal decomposition continuous method, and the method is specific
For：(1) using chromic acid as raw material, returning charge, additive mixing is added, returning charge accounts for the 3-7% of total material, additive accounts for the 0.2- of total material
0.6%；Returning charge is thick chrome green；Additive is selected from boric acid, ammonium chloride, starch, sawdust, preferred boric acid；(2) in microcomputer control
Under system, after mixing by material, quantitative input heat preservation rotary kiln fuel injector tip makees roasting fuel with liquefied gas, directly with
Material contacts cocurrent burning, and in rotary kiln slowly uniform rotary course, material quickly enters high-temperature region and roasted, high temperature
Area's temperature is 1000-1150 DEG C；Reaction time is 40-60 minutes；After violent pyrolysis, chromic acid is converted into three oxidations two
Chromium；(3) it after chrome green keeps the temperature 80-120 minutes in rotary kiln, is come out from rotary kiln, drop temperature 420-450
DEG C, qualified chrome green product is become after cooling, crushing；(4) three oxidations two not crushed after cooling in step (3)
Chromium is proportionally added into raw material to be roasted as returning charge.The method solve the main content of traditional chromic acid thermal decomposition method it is low, remaining six
The disadvantages such as valence chromium and water-soluble salt are high, the thermal efficiency is low.But the method requires equipment and operation high, additive and returning charge increase
Energy consumption in production process, additive narrow application range.
Therefore, it is also desirable to the minimizing technology of Cr VI in chrome oxide green further be probed into, to better adapt to industrial production.
Invention content
In view of the deficiencies of the prior art, the present invention intends to provide Cr VI in a kind of reduction chrome oxide green to contain
The method of amount, the method can reduce the content of Cr VI in chrome oxide green so that the water solubles content of chrome oxide green product
It reduces, solves the problems, such as that product colour turns to be yellow, and improve the rate of recovery of crome metal.
Cr VI in the chrome oxide green refers to a part of oxidisability of generation in the production process of chrome oxide green
By force, the high Cr VI of activity, this part Cr VI can not only increase product water solubles content, and product colour can be made to send out
Huang has large effect to product use.
In the present invention unless otherwise specified, the wt.% refers to mass percentage.
For this purpose, the present invention uses following technical scheme：
A kind of method of content of 6-valence Cr ions in reduction chrome oxide green, the method includes：Temperature during discharging to production
For reducing agent is added in 60-400 DEG C of chrome oxide green, chrome oxide green product is obtained.
The method is by being added reducing agent, and using the waste heat in chrome oxide green temperature-fall period by the raw material chromium oxide
Hexavalent chrome reduction in green, to reduce the content of Cr VI in raw material chrome oxide green.
Reduction of the reducing agent to the Cr VI in chrome oxide green is added in chrome oxide green during from the discharging to production
It is most important, only to production process there is the chrome oxide green of certain temperature (60-400 DEG C) reducing agent is added, could obtain good
The effect of Cr VI in good reduction chrome oxide green.If reducing agent is added in the raw material for preparing chrome oxide green, with raw material
It is reacted together, the effect of reducing agent reduction of hexavalent chromium is significantly reduced；In addition, 60 DEG C of chrome oxide greens below will be cooled to
It is again heated to 60-400 DEG C after being mixed with reducing agent, the ability of Cr VI can also decline to a great extent in reducing agent reduction-oxidation chrome green.
As long as the reducing agent has reproducibility, it is preferable that the reducing agent is in ammonium salt, ammonium hydroxide, alcohol or aldehyde
Any one or at least two combination, preferably ammonium chloride.Typical but non-limiting combination such as ammonium salt and ammonium hydroxide, ammonium salt
With alcohol, ammonium salt and aldehyde, alcohol and aldehyde, ammonium hydroxide, alcohol and aldehyde etc..
Preferably, to production discharge during temperature be 350-400 DEG C (such as 355 DEG C, 360 DEG C, 365 DEG C, 370 DEG C, 375
DEG C, 380 DEG C, 385 DEG C, 390 DEG C or 395 DEG C etc., be added at a temperature of this arbitrary in ammonium chloride, ammonium hydroxide, ethylene glycol or glyoxal
A kind of or at least two combined effects are more preferable) chrome oxide green in be added in the ammonium chloride, ammonium hydroxide, ethylene glycol or glyoxal
Any one or at least two combination, typical but non-limiting combination is such as ammonium chloride and ammonium hydroxide, ammonium hydroxide and ethylene glycol, second
Glycol and glyoxal, ammonium hydroxide, ethylene glycol and glyoxal.
Preferably, the ethyl alcohol is added in the chrome oxide green that temperature is 60-120 DEG C during discharging to production, such as to life
During output material temperature be 65 DEG C, 70 DEG C, 75 DEG C, 80 DEG C, 85 DEG C, 90 DEG C, 95 DEG C, 100 DEG C, 102 DEG C, 103 DEG C, 105 DEG C,
The ethyl alcohol is added in 108 DEG C or 116 DEG C etc. of chrome oxide green, ethyl alcohol is added at a temperature of this, effect is more preferable.
As a preferred technical solution, first to the production discharge during temperature for 350-400 DEG C (such as 355 DEG C, 360
DEG C, 365 DEG C, 370 DEG C, 375 DEG C, 380 DEG C, 385 DEG C, 390 DEG C or 395 DEG C etc.) chrome oxide green in ammonium chloride, ethylene glycol is added
In glyoxal any one or at least two combination (typical but non-limiting combination such as ammonium chloride and ethylene glycol, chlorine
Change ammonium and glyoxal, ammonium chloride, ethylene glycol and glyoxal), then be cooled to 60-120 DEG C (such as 65 DEG C, 70 DEG C, 75 DEG C, 80 DEG C, 85
DEG C, 90 DEG C, 95 DEG C, 100 DEG C, 102 DEG C, 103 DEG C, 105 DEG C, 108 DEG C or 116 DEG C etc.) when ethyl alcohol is added.
In typical but non-limiting ammonium salt such as ammonium chloride, ammonium nitrate or ammonium sulfate any one or at least two group
It closes.The combination for example can be：Ammonium chloride and ammonium nitrate, ammonium chloride and ammonium sulfate, ammonium nitrate and ammonium sulfate, ammonium chloride, nitre
Sour ammonium and ammonium sulfate.
In typical but non-limiting alcohol such as ethyl alcohol, ethylene glycol or glycerine any one or at least two combination.
The combination for example can be ethyl alcohol and ethylene glycol, ethyl alcohol and glycerine, ethyl alcohol, ethylene glycol and glycerine.
In typical but non-limiting aldehyde such as acetaldehyde, propionic aldehyde or glyoxal any one or at least two combination.Institute
It can be acetaldehyde and propionic aldehyde, acetaldehyde and glyoxal, acetaldehyde, propionic aldehyde and glyoxal to state combination for example.
It is highly preferred that the reducing agent in ammonium chloride, ammonium hydroxide, ethyl alcohol, ethylene glycol or glyoxal any one or
At least two combination.
The additive amount of the reducing agent be raw material chrome oxide green total chrome 2wt.%-15wt.%, as 3wt.%,
4wt.%, 66wt.%, 7wt.%, 8wt.%, 9wt.%, 12wt.%, 13wt.% or 14wt.% etc., preferably 5wt.%-
10wt.%.
The mode that the reducing agent is added is：The reducing agent is configured to solution, is sprayed onto in raw material chrome oxide green, makes
Obtaining the reducing agent solution can come into full contact with raw material chrome oxide green, penetrate into.
Preferably, when the reducing agent is ammonium salt, the solution is saturated solution.It is handled using the ammonium salt solution of saturation
Cr VI effect in chrome oxide green is more preferable.
It is also kept the temperature and is cooled down after the addition reducing agent.
Preferably, the time of the heat preservation is 1~2h, such as 1.2h, 1.3h, 1.4h, 1.5h, 1.6h, 1.7h or 1.9h.
Preferably, the temperature after the cooling be 10~35 DEG C, such as 12 DEG C, 15 DEG C, 18 DEG C, 20 DEG C, 23 DEG C, 25 DEG C, 28
DEG C, 30 DEG C or 32 DEG C etc..
Reducing agent is added in the chrome oxide green that temperature is 60-400 DEG C during discharging to production, such as to production discharging process
Middle temperature be 70 DEG C, 80 DEG C, 90 DEG C, 100 DEG C, 120 DEG C, 150 DEG C, 180 DEG C, 200 DEG C, 220 DEG C, 250 DEG C, 280 DEG C, 300 DEG C,
320 DEG C, 360 DEG C or 380 DEG C etc. of chrome oxide green is mixed with reducing agent, and temperature is 100-350 during preferably discharging to production
DEG C chrome oxide green in reducing agent is added.
The chrome oxide green is thermally decomposed to yield by chromic anhybride, and the chromic anhybride is preferably chromic anhybride high-class product.The chromium
It is technology well known in the art that acid anhydrides thermal decomposition, which prepares raw material chrome oxide green, and therefore not to repeat here.
The cooling is preferably natural cooling.
Described method includes following steps as a preferred technical solution,：
(1) reducing agent is configured to reducing agent solution；
(2) method for utilizing chromic anhybride thermal decomposition prepares chrome oxide green, and 60-400 DEG C is down in chrome oxide green drop temperature
When, reducing agent solution is sprayed onto in the chrome oxide green, 1~2h is kept the temperature, later, natural cooling 2 hours or more is aoxidized
Chrome green product, wherein the quality of reducing agent is the 2wt.%-15wt.% of total chrome in chrome oxide green in the reducing agent solution.
Numberical range of the present invention includes not only enumerated point value, further includes the above-mentioned numerical value not included
Arbitrary point value between range, as space is limited and for concise consideration, range includes described in the present invention no longer exclusive list
Specific point value.
In addition, adding the reducing agent and cooling procedure can carry out in the environment of being either open or closed.
The present invention can divide the Cr VI in product according to GB9760-88 and GB20785-2006 the methods
Analysis.
Compared with prior art, beneficial effects of the present invention are：
The method of content of 6-valence Cr ions can reduce the Cr VI in chrome oxide green in reduction chrome oxide green provided by the invention,
So that the water solubles content of chrome oxide green product reduces, solve the problems, such as that product colour turns to be yellow, and simultaneously by sexavalence in chrome oxide green
Chromium is reduced to trivalent chromium, improves the rate of recovery of crome metal.
The method of content of 6-valence Cr ions is easy to operate in reduction chrome oxide green provided by the invention, and reducing agent dosage is few, is dropping
It is added, original technique is not had an impact during temperature, and reducing agent volatilizees decomposition in reduction process, it will not be to chrome oxide green
Purity impacts.
Specific implementation mode
The technical solution further illustrated the present invention below by specific implementation mode.
Two kinds of chromic anhybrides, quality are used to meet respectively in chromic anhybride standard GB/T 1610-1999 in following embodiment altogether
Grade A (being denoted as chromic anhybride 1) 1 and high-class product (being denoted as chromic anhybride 2).
Heretofore described room temperature refers to 10 DEG C -40 DEG C.
Embodiment 1
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, when Muffle furnace is cooled to 400 DEG C, is added
2.5mL ammonium chloride saturated solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, to chromium oxide
Cr VI in green carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 779mgkg when being not added with-1It is down to 254mgkg-1。
Embodiment 2
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, when Muffle furnace is cooled to 100 DEG C, is added
0.2mL ethanol solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, in chrome oxide green
Cr VI carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ethyl alcohol, in chrome oxide green product
Soluble chromium content can be by 779mgkg when being not added with-1Drop to 178mgKg-1。
Embodiment 3
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 2, thermally decomposes 1h, when Muffle furnace is cooled to 400 DEG C, is added
2.5mL ammonium chloride saturated solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, to chromium oxide
Cr VI in green carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 260mgkg when being not added with-1It is down to 31mgkg-1。
Embodiment 4
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 2, thermally decomposes 1h, when Muffle furnace is cooled to 100 DEG C, is added
0.2mL ethanol solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, in chrome oxide green
Cr VI carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ethyl alcohol, in chrome oxide green product
Soluble chromium content can be by 260mgkg when being not added with-1Drop to 26mgKg-1。
Embodiment 5
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 2, thermally decomposes 1h, when Muffle furnace is cooled to 100 DEG C, is added
20mL ethanol solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, to six in chrome oxide green
Valence chromium carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ethyl alcohol, in chrome oxide green product
Soluble chromium content can be by 260mgkg when being not added with-1Drop to 7mgKg-1。
Embodiment 6
It takes and is heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 350 DEG C, spray 2.5mL saturated ammonium chloride solutions,
Continue to cool down, when being cooled to 60 DEG C, sprays 1.5mL ethyl alcohol, cooled to room temperature.According to GB9760-88, GB20785-2006
Method, in chrome oxide green Cr VI carry out extractive analysis, it is as a result as follows：
Chromium Content Analysis is carried out using ICP, after adding ammonium chloride and ethyl alcohol during chromic anhybride decomposes temperature-fall period, chromium oxide
Soluble chromium content can be by 260mgkg when being not added in green product-1Drop to 3mgKg-1。
Embodiment 7
It takes and is heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 400 DEG C, spray 0.47mL ethylene glycol solutions, after
Continuous cooling when being cooled to 100 DEG C, sprays 2.3mL ethyl alcohol, cooled to room temperature.According to GB9760-88, GB20785-2006
Method, in chrome oxide green Cr VI carry out extractive analysis, it is as a result as follows：
Chromium Content Analysis is carried out using ICP, after adding ethylene glycol and ethyl alcohol during chromic anhybride decomposes temperature-fall period, chromium oxide
Soluble chromium content can be by 260mgkg when being not added in green product-1Drop to 9mgKg-1。
Embodiment 8
It takes and is heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 400 DEG C, while spraying 0.2mL ethylene glycol solutions
And 2.5mL ammonium chloride solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, to chrome oxide green
In Cr VI carry out extractive analysis, it is as a result as follows：
Chromium Content Analysis is carried out using ICP, after adding ethylene glycol and ammonium chloride during chromic anhybride decomposes temperature-fall period, oxidation
Soluble chromium content can be by 260mgkg when being not added in chrome green product-1Drop to 22mgKg-1。
Embodiment 9
Take and be heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 400 DEG C, while spray 0.65mL glyoxals and
2.5mL ammonium chloride solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, in chrome oxide green
Cr VI carry out extractive analysis, it is as a result as follows：
Chromium Content Analysis is carried out using ICP, after adding glyoxal and ammonium chloride during chromic anhybride decomposes temperature-fall period, oxidation
Soluble chromium content can be by 260mgkg when being not added in chrome green product-1Drop to 18mgKg-1。
Embodiment 10
Take and be heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 400 DEG C, while spray 0.65mL glyoxals and
0.47mL ethylene glycol solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, in chrome oxide green
Cr VI carry out extractive analysis, it is as a result as follows：
Chromium Content Analysis is carried out using ICP, after adding glyoxal and ethylene glycol during chromic anhybride decomposes temperature-fall period, oxidation
Soluble chromium content can be by 260mgkg when being not added in chrome green product-1Drop to 102mgKg-1。
Embodiment 11
Take and be heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 400 DEG C, while spray 0.65mL glyoxals and
2.3mL ammonia spirits, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, in chrome oxide green
Cr VI carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, it is solvable in chrome oxide green product after being added during chromic anhybride decomposes temperature-fall period
Property chromium content can be by 260mgkg when being not added with-1Drop to 68mgKg-1。
Embodiment 12
It takes and is heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 350 DEG C, spray 0.65mL glyoxal solutions, after
Continuous cooling when being cooled to 100 DEG C, sprays 1.5mL ethyl alcohol, cooled to room temperature.According to GB9760-88, GB20785-2006
Method, in chrome oxide green Cr VI carry out extractive analysis, it is as a result as follows：
Chromium Content Analysis is carried out using ICP, it is solvable in chrome oxide green product after being added during chromic anhybride decomposes temperature-fall period
Property chromium content can be by 260mgkg when being not added with-1Drop to 9mgKg-1。
Embodiment 13
It takes and is heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 200 DEG C, spray 2.0mL glyoxal solutions, it is natural
It is cooled to room temperature.According to the method for GB9760-88, GB20785-2006, extractive analysis is carried out to the Cr VI in chrome oxide green,
As a result as follows：
Chromium Content Analysis is carried out using ICP, it is solvable in chrome oxide green product after being added during chromic anhybride decomposes temperature-fall period
Property chromium content can be by 260mgkg when being not added with-1Drop to 115mgKg-1。
Embodiment 14
It takes and is heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 300 DEG C, sprinkling 2.0mL is saturated ammonium hydroxide, naturally cold
But to room temperature.According to the method for GB9760-88, GB20785-2006, extractive analysis, knot are carried out to the Cr VI in chrome oxide green
Fruit is as follows：
Chromium Content Analysis is carried out using ICP, it is solvable in chrome oxide green product after being added during chromic anhybride decomposes temperature-fall period
Property chromium content can be by 260mgkg when being not added with-1Drop to 154mgKg-1。
Embodiment 15
It takes and is heat-treated under the conditions of 2,950 DEG C of 15g chromic anhybrides, when being cooled to 100 DEG C, spray 1.5mL ethylene glycol, natural cooling
To room temperature.According to the method for GB9760-88, GB20785-2006, extractive analysis is carried out to the Cr VI in chrome oxide green, as a result
It is as follows：
Chromium Content Analysis is carried out using ICP, it is solvable in chrome oxide green product after being added during chromic anhybride decomposes temperature-fall period
Property chromium content can be by 260mgkg when being not added with-1Drop to 130mgKg-1。
Tests prove that when the ammonium salt is other ammonium salts in addition to ammonium chloride, can also be used for reducing oxidation
The reducing agent of content of 6-valence Cr ions in chrome green under the same conditions, can drop soluble chromium content with the condition of embodiment 1
Down to 260~482mgkg-1。
When other alcohol except the alcohol is ethyl alcohol and ethylene glycol, it can also be used for reducing Cr VI in chrome oxide green and contain
Soluble chromium content can be reduced to 180~557mgkg by the reducing agent of amount under the same conditions as in practical example 2-1。
When the aldehyde be glyoxal except other aldehyde when, can also be used for reduce chrome oxide green in content of 6-valence Cr ions also
Soluble chromium content under the same conditions, can be reduced to 120~180mgkg by former agent with embodiment 13-1。
Comparative example 1
14.5g chromic anhybrides 2, the thick chrome oxide greens of 0.4g is taken (to be produced in 950 DEG C of thermal decompositions by chromic anhybride 1), 0.03g chlorinations
Ammonium, batch mixing is uniform, is heat-treated in 1000 DEG C of Muffle furnaces, reaction time 40min, keeps the temperature 80min, natural cooling cooling.According to
The method of GB9760-88, GB20785-2006 carry out extractive analysis to the Cr VI in chrome oxide green, as a result as follows：
Method described in this embodiment referenced patent CN1459419A carries out, and Chromium Content Analysis is carried out using ICP, in chromic acid
Before acid anhydride thermal decomposition after addition ammonium chloride and thick chrome oxide green, soluble chromium content can be by when being not added in chrome oxide green product
779mg·kg-1It is down to 450mgkg-1。
Comparative example 2
13.9g chromic anhybrides 2, the thick chrome oxide greens of 1.0g is taken (to be produced in 950 DEG C of thermal decompositions by chromic anhybride 1), 0.08g chlorinations
Ammonium, batch mixing is uniform, is heat-treated in 1150 DEG C of Muffle furnaces, reaction time 60min, keeps the temperature 120min, natural cooling cooling.According to
The method of GB9760-88, GB20785-2006 carry out extractive analysis to the Cr VI in chrome oxide green, as a result as follows：
Method described in this embodiment referenced patent CN1459419A carries out, and Chromium Content Analysis is carried out using ICP, in chromic acid
Before acid anhydride thermal decomposition after addition ammonium chloride and thick chrome oxide green, soluble chromium content can be by when being not added in chrome oxide green product
260mg·kg-1It is down to 441mgkg-1。
Comparative example 3
14.5g is taken to contain Cr2O3>=99.5% raw material, the thick chrome oxide greens of 0.4g (are thermally decomposed system by chromic anhybride 1 at 950 DEG C
Take), 0.03g ammonium chlorides, batch mixing is uniform, is heat-treated in 1000 DEG C of Muffle furnaces, reaction time 40min, keeps the temperature 80min, natural
It cools.According to the method for GB9760-88, GB20785-2006, extractive analysis, knot are carried out to the Cr VI in chrome oxide green
Fruit is as follows：
Method described in this embodiment referenced patent CN1459419A carries out, and Chromium Content Analysis is carried out using ICP, in chromic acid
Before acid anhydride thermal decomposition after addition ammonium chloride and thick chrome oxide green, soluble chromium content can be by when being not added in chrome oxide green product
270mg·kg-1It is down to 260mgkg-1。
Comparative example 4
The chloride solid of quality same as Example 1 is mixed with chromic anhybride 1 and is thermally decomposed, then naturally cools to room
Temperature.According to the method for GB9760-88, GB20785-2006, extractive analysis is carried out to the Cr VI in chrome oxide green, as a result such as
Under：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 779mgkg when being not added with-1It is down to 362mgkg-1。
Comparative example 5
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, cooled to room temperature is added later
2.5mL ammonium chloride saturated solutions, when being heated to 400 DEG C, according to the method for GB9760-88, GB20785-2006, to oxidation
Cr VI in chrome green carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 779mgkg when being not added with-1It is down to 752mgkg-1。
Comparative example 6
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, cooled to room temperature is added later
2.5mL ammonium chloride saturated solutions, when being heated to 60 DEG C, according to the method for GB9760-88, GB20785-2006, to oxidation
Cr VI in chrome green carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 779mgkg when being not added with-1It is down to 709mgkg-1。
Comparative example 7
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, cooled to room temperature is added later
2.5mL ammonium chloride saturated solutions, when being heated to 350 DEG C, according to the method for GB9760-88, GB20785-2006, to oxidation
Cr VI in chrome green carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 779mgkg when being not added with-1It is down to 562mgkg-1。
Comparative example 8
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, when Muffle furnace is cooled to 420 DEG C, is added
2.5mL ammonium chloride saturated solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, to chromium oxide
Cr VI in green carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 779mgkg when being not added with-1It is down to 640mgkg-1。
Comparative example 9
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, when Muffle furnace is cooled to 55 DEG C, is added
2.5mL ammonium chloride saturated solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, to chromium oxide
Cr VI in green carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ammonium chloride, chrome oxide green product
Middle soluble chromium content can be by 779mgkg when being not added with-1It is down to 714mgkg-1。
Comparative example 10
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, when Muffle furnace is cooled to 420 DEG C, is added
0.2mL ethanol solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, in chrome oxide green
Cr VI carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ethyl alcohol, in chrome oxide green product
Soluble chromium content can be by 779mgkg when being not added with-1Drop to 697mgKg-1。
Comparative example 11
Muffle furnace heat up to 950 DEG C, is put into 15g chromic anhybrides 1, thermally decomposes 1h, when Muffle furnace is cooled to 55 DEG C, is added
0.2mL ethanol solutions, cooled to room temperature.According to the method for GB9760-88, GB20785-2006, in chrome oxide green
Cr VI carries out extractive analysis, as a result as follows：
Chromium Content Analysis is carried out using ICP, in chromic anhybride decomposes temperature-fall period after addition ethyl alcohol, in chrome oxide green product
Soluble chromium content can be by 779mgkg when being not added with-1Drop to 449mgKg-1。
In addition, the ammonium chloride in comparative example 4-9 is replaced with any one in same amount of ethylene glycol, ethyl alcohol or glyoxal
Kind or at least two combination, soluble chromium content can be by 779mgkg when being not added in chrome oxide green product-1It is down to 320
~720mgkg-1, wherein the ammonium chloride in comparative example 4 replaces with arbitrary in same amount of ethylene glycol, ethyl alcohol or glyoxal
It is a kind of or at least two combination when, soluble chromium content can be by 779mgkg when being not added in chrome oxide green product-1It is down to
320~380mgkg-1, the ammonium chloride in remaining comparative example replaces after additive that soluble chromium content can in chrome oxide green product
779mgkg when by being not added with-1It is down to 700~720mgkg-1。
Applicant states that the present invention illustrates the method detailed of the present invention, but the present invention not office by above-described embodiment
It is limited to above-mentioned method detailed, that is, does not mean that the present invention has to rely on above-mentioned method detailed and could implement.Technical field
Technical staff it will be clearly understood that any improvement in the present invention, equivalence replacement and auxiliary element to each raw material of product of the present invention
Addition, the selection etc. of concrete mode, all fall within protection scope of the present invention and the open scope.
Claims (10)
1. a kind of method reducing content of 6-valence Cr ions in chrome oxide green, which is characterized in that the method includes：It discharged to production
Reducing agent is added in the chrome oxide green that temperature is 60-400 DEG C in journey, obtains chrome oxide green product.
2. according to the method described in claim 1, it is characterized in that, the reducing agent appointing in ammonium salt, ammonium hydroxide, alcohol or aldehyde
It anticipates a kind of or at least two combinations.
3. method according to claim 1 or 2, which is characterized in that the reducing agent is selected from ammonium chloride, ammonium hydroxide, ethyl alcohol, second
In glycol or glyoxal any one or at least two combination, preferably ammonium chloride；
Preferably, the ammonium chloride, ammonium hydroxide, second is added in the chrome oxide green that temperature is 350-400 DEG C during discharging to production
In glycol or glyoxal any one or at least two combination；
Preferably, the ethyl alcohol is added in the chrome oxide green that temperature is 60-120 DEG C during discharging to production.
4. according to the method described in one of claim 1-3, which is characterized in that temperature is during first discharging to the production
Any one in ammonium chloride, ethylene glycol or glyoxal or at least two combinations are added in 350-400 DEG C of chrome oxide green, then drop
Ethyl alcohol is added when temperature is to 60-120 DEG C.
5. according to the method described in one of claim 1-4, which is characterized in that the additive amount of the reducing agent is raw material chromium oxide
The 2wt.%-15wt.% of green total chrome, preferably 5wt.%-10wt.%.
6. according to the method described in one of claim 1-5, which is characterized in that the mode that the reducing agent is added is：It will be described
Reducing agent is configured to solution, is sprayed onto in raw material chrome oxide green；
Preferably, when the reducing agent is ammonium salt, the solution is saturated solution.
7. according to the method described in one of claim 1-6, which is characterized in that also kept the temperature and dropped after the addition reducing agent
Temperature；
Preferably, the time of the heat preservation is 1~2h；
Preferably, the temperature after the cooling is 10~35 DEG C；
Preferably, the cooling is natural cooling.
8. according to the method described in one of claim 1-7, which is characterized in that temperature is 100-350 DEG C during to discharging
Reducing agent is added in chrome oxide green.
9. according to the method described in one of claim 1-8, which is characterized in that the chrome oxide green is thermally decomposed by chromic anhybride
It arrives, the chromic anhybride is preferably chromic anhybride high-class product.
10. according to the method described in one of claim 1-9, which is characterized in that described method includes following steps：
(1) reducing agent is configured to reducing agent solution；
(2) method for utilizing chromic anhybride thermal decomposition prepares chrome oxide green, will when chrome oxide green drop temperature is down to 60-400 DEG C
Reducing agent solution is sprayed onto in the chrome oxide green, keeps the temperature 1~2h, and later, natural cooling 2 hours or more obtains chrome oxide green
Product, wherein the quality of reducing agent is the 2wt.%-15wt.% of total chrome in chrome oxide green in the reducing agent solution.
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| CN112194183A (en) * | 2020-10-12 | 2021-01-08 | 甘肃锦世化工有限责任公司 | Method for producing chromium oxide green with low soluble chromium and zero hexavalent chromium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4230677A (en) * | 1978-11-30 | 1980-10-28 | Union Carbide Corporation | Recovery of Cr2 O3 from a chromium bearing solution |
| CN103253709A (en) * | 2013-05-29 | 2013-08-21 | 甘肃锦世化工有限责任公司 | Method for producing chromium sesquioxide through hot method |
| CN105861829A (en) * | 2016-04-18 | 2016-08-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for separating vanadium and chromium solution and recycling vanadium and chromium |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4230677A (en) * | 1978-11-30 | 1980-10-28 | Union Carbide Corporation | Recovery of Cr2 O3 from a chromium bearing solution |
| CN103253709A (en) * | 2013-05-29 | 2013-08-21 | 甘肃锦世化工有限责任公司 | Method for producing chromium sesquioxide through hot method |
| CN105861829A (en) * | 2016-04-18 | 2016-08-17 | 攀钢集团攀枝花钢铁研究院有限公司 | Method for separating vanadium and chromium solution and recycling vanadium and chromium |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112194183A (en) * | 2020-10-12 | 2021-01-08 | 甘肃锦世化工有限责任公司 | Method for producing chromium oxide green with low soluble chromium and zero hexavalent chromium |
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