CN103694097A - Method for preparing menadione co-production chrome tanning agent with chromium-enriched sludge - Google Patents
Method for preparing menadione co-production chrome tanning agent with chromium-enriched sludge Download PDFInfo
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- CN103694097A CN103694097A CN201310729810.6A CN201310729810A CN103694097A CN 103694097 A CN103694097 A CN 103694097A CN 201310729810 A CN201310729810 A CN 201310729810A CN 103694097 A CN103694097 A CN 103694097A
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- China
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- vitamin
- chrome tanning
- tanning agent
- chromium
- rich chromium
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C46/00—Preparation of quinones
- C07C46/02—Preparation of quinones by oxidation giving rise to quinoid structures
- C07C46/04—Preparation of quinones by oxidation giving rise to quinoid structures of unsubstituted ring carbon atoms in six-membered aromatic rings
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G37/00—Compounds of chromium
- C01G37/08—Chromium sulfates
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
-
- C—CHEMISTRY; METALLURGY
- C14—SKINS; HIDES; PELTS; LEATHER
- C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
- C14C3/00—Tanning; Compositions for tanning
- C14C3/02—Chemical tanning
- C14C3/04—Mineral tanning
- C14C3/06—Mineral tanning using chromium compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/20—Heavy metals or heavy metal compounds
- C02F2101/22—Chromium or chromium compounds, e.g. chromates
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/22—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof
- C02F2103/24—Nature of the water, waste water, sewage or sludge to be treated from the processing of animals, e.g. poultry, fish, or parts thereof from tanneries
Abstract
The invention belongs to the technical field of chemical engineering, and particularly relates to a method for preparing a menadione co-production chrome tanning agent with chromium-enriched sludge. The method for preparing the menadione co-production chrome tanning agent with the chromium-enriched sludge is characterized by comprising the following steps of: (1) pretreating the chromium-enriched sludge, (2) preparing menadione oxidation liquid, (3) preparing menadione, and (4) preparing the chrome tanning agent. The method takes the chromium-enriched sludge as a raw material and is a recycle technology for producing the menadione co-production chrome tanning agent, the tanning chromium-enriched sludge is totally recycled to produce the chrome tanning agent for tanning, more menadione products can also be produced, the problems in discharge and disposal of chromium-bearing solid hazardous wastes of a tanning enterprise are solved, menadione and the chrome tanning agent can be produced at the same time, and environmental and economic benefits are significant.
Description
Technical field
The invention belongs to chemical technology field, be specifically related to a kind of method that rich chromium mud is prepared vitamin k4 coproduction chrome tanning agent.
background technology
The monitoring management of state key industry heavy metals emission has been listed in tanning industry pollution of chromium discharge in.The research of current rich chromium mud mainly concentrates on leather-making enterprises internal recycling and uses, and Ye Youjian leather chemical industry enterprise contains chrome tanning agent and retanning agent product as single exploitation.But utilize the rich chromium sludge disposal of leather industry and produce vitamin k4 coproduction chrome tanning agent product, solving two industry environment pollution problems simultaneously, still belonging to precedent.Economy solves industrial enterprise's environmental issue, breaks through vein Economic Development Mode, is that present method is attempted the technological breakthrough of walking out.
China's leather industry sewage effluent is more than 100,000,000 tons, 3500 tons of chromium, 5000 tons of sulphur, 150,000 tons of chemical oxygen demands, the discharge of a large amount of noxious pollutants has caused harm to environment, if have suitable technique that part pollutent is recycled, by effective recycling, produce certain economic and social benefit.
A large amount of chromium mud that leather-making enterprises produces have brought environmental problem, meanwhile, chromium is as one of of paramount importance chemical materials in process hides operation, just becoming more and more rare, therefore, we attempt exploring the feasibility that chromium mud is recycled, be based on existing chromium sludge treatment problem, study the recycling that utilizes chromium mud to prepare chrome tanning agent, reduced again the pollution of chromium-bearing sludge to environment, can create good economic and social benefit.
Summary of the invention
In order to solve above-mentioned technical problem, the invention provides a kind of method that rich chromium mud is prepared vitamin k4 coproduction chrome tanning agent.
The rich chromium mud of the present invention is prepared the method for vitamin k4 coproduction chrome tanning agent, is to realize by following technical scheme:
Rich chromium mud is prepared a method for vitamin k4 coproduction chrome tanning agent, and the method comprises following step:
(1) rich chromium mud pretreatment:
By rich chromium mud oven dry to its moisture content, be 1-5%, after pulverizing by ball mill, rich chromium mud, sodium hydroxide and sodium carbonate mixed by following part by weight, standby;
Rich chromium mud: chromium hydroxide: sodium carbonate=1-30:1-5:1-10;
(2) prepare vitamin k4 oxidation solution:
Get chromium hydroxide and be crushed to 20-60 order, chromium hydroxide powder after pulverizing is added and is placed in retort furnace aerobic roasting under the condition of 400-600 ℃, then roasting material is carried out to circulating leaching, after filtration, in filtrate, add sulfuric acid, the add-on of described sulfuric acid is 10-30 times of chromium hydroxide powder weight, obtains vitamin k4 oxidation solution;
(3) vitamin k4 preparation:
In there-necked flask, add methylnaphthalene, water, emulsifying agent, the weight ratio of methylnaphthalene, water and emulsifying agent is 1-3:5-40:1-4, then start to use oxidation solution drop reaction, control temperature 40-70 ℃, control titration time is 2-5 hour, and reaction finishes rear filtration, and washing leaching cake, filter cake is vitamin k4, after filtrate collection for the preparation of chrome tanning agent;
(4) chrome tanning agent preparation:
In above-mentioned filtrate, adding reductive agent, is trivalent chromium by sexavalent chrome Restore All wherein, adjusts basicity, and still aging 4-20h, obtains chrome tanning agent.
Above-mentioned rich chromium mud is that tannery's chrome tanning process produces the hazardous solid waste that waste water produces through alkali precipitation technology, and the butt effective constituent of described rich chromium mud is chromium hydroxide, protein.
Above-mentioned reductive agent is low molecule organic matter or inorganics, and described low molecule organic matter is any in glucose, molasses, starch; Described inorganics is sulfurous gas, burnt sodium.
Preferably, above-mentioned rich chromium mud: chromium hydroxide: the ratio of weight and number of sodium carbonate is 25:2:2.
Above-mentioned step is crushed to 40 orders by chromium hydroxide in (2).
The add-on of the middle sulfuric acid of above-mentioned step (2) is 20 times of chromium hydroxide powder weight.
In the preparation of above-mentioned step (3) vitamin k4:
In there-necked flask, add methylnaphthalene, water, emulsifying agent, the weight ratio of methylnaphthalene, water and emulsifying agent is 2:30:3, then start to use oxidation solution drop reaction, control temperature 60 C, controlling titration time is 3 hours, and reaction finishes rear filtration, and washing leaching cake, filter cake is vitamin k4, after filtrate collection for the preparation of chrome tanning agent.
In above-mentioned step (1), by rich chromium mud oven dry to its moisture content, be 2%.
Preferably, in step (4), the still aging time is 8 hours.
Reaction mechanism of the present invention is:
What vitamin k4 produced after producing is the product that produces in raw material excessive in reaction (3) and the reaction process mixture except vitamin k4 containing chromium filtrate.
Reaction (3), (4) become chromic process for redox reaction is about to sexavalent chrome Restore All, and reaction (4) is for adding the reaction after glucose, and other reductive agents in like manner.
Beneficial effect of the present invention is, adopting method of the present invention to take rich chromium mud is raw material, be to produce vitamin k4 coproduction chrome tanning agent reutilization technology, make the rich chromium mud of process hides except can all realizing recycling production process hides with producing vitamin k4 product chrome tanning agent more; Both solved the discharge handling problems of leather-making enterprises containing chromium solid dangerous waste, can produce vitamin k4 and chrome tanning agent, environmental benefit and remarkable in economical benefits simultaneously.
Embodiment
Below in conjunction with specific embodiment, the present invention is further described, so that those skilled in the art more understands the present invention, but does not therefore limit the present invention.
Embodiment 1
Rich chromium mud is prepared a method for vitamin k4 coproduction chrome tanning agent, and the method comprises following step:
(1) rich chromium mud pretreatment:
By rich chromium mud oven dry to its moisture content, be 2%, after pulverizing by ball mill, rich chromium mud, sodium hydroxide and sodium carbonate mixed by following part by weight, standby;
Rich chromium mud: chromium hydroxide: sodium carbonate=25:2:2;
(2) prepare vitamin k4 oxidation solution:
Get chromium hydroxide and be crushed to 40 orders, chromium hydroxide powder after pulverizing is added and is placed in retort furnace aerobic roasting under the condition of 500 ℃ of left and right, then roasting material is carried out to circulating leaching, after filtration, in filtrate, add sulfuric acid, the add-on of described sulfuric acid is 230 times of chromium hydroxide powder weight, obtains vitamin k4 oxidation solution;
(3) vitamin k4 preparation:
In there-necked flask, add methylnaphthalene, water, emulsifying agent, the weight ratio of methylnaphthalene, water and emulsifying agent is 2:30:3, then start to use oxidation solution drop reaction, control temperature 60 C, controlling titration time is 3 hours, and reaction finishes rear filtration, and washing leaching cake, filter cake is vitamin k4, after filtrate collection for the preparation of chrome tanning agent;
(4) chrome tanning agent preparation:
In above-mentioned filtrate, adding reductive agent, is trivalent chromium by sexavalent chrome Restore All wherein, adjusts basicity, and still aging 8h, obtains chrome tanning agent.
Rich chromium mud is that tannery's chrome tanning process produces the hazardous solid waste that waste water produces through alkali precipitation technology, and the butt effective constituent of described rich chromium mud is chromium hydroxide, protein.
Reductive agent is inorganics sulfurous gas.
Chrome tanning agent of the present invention performance as follows:
The wet blue leather of chrome tanning agent tanning of the present invention, the leather of its finished leather color and luster and the tanning of standard industry chromium powder differs little, and good hand feeling is also better aspect tanning performance and organoleptic properties, Cr in tanned chromium waste liquid
2o
3content, lower than 2g/L, from different sites sampling, is surveyed shrinkage temperature, is all more than or equal to 98 ℃, good hand feeling, and softness, illustrates that tanning effect is better.
In tanning agents of the present invention, chromium content has reached 24.6%, 25.0% comparatively approaching with standard chromium powder, and the basicity of two kinds of chromium powders and pH value are also more or less the same.
Product tear edge of the present invention is 75.6N; Elongation at break is 62.1%; Tensile strength is 16.9Mpa; Tear strength is 45.1N/mm;
Product finished leather shrinkage temperature of the present invention is 98 ℃, the Cr in finished leather
2o
3content, tear edge, tear strength, elongation at break, tensile strength indices are all comparatively approaching, and the be near the mark tanning performance of chromium powder of the chrome tanning agent performance that shows to regenerate, can substitute or part alternate standard chromium powder is produced for tanning.
Embodiment 2
Rich chromium mud is prepared a method for vitamin k4 coproduction chrome tanning agent, and the method comprises following step:
(1) rich chromium mud pretreatment:
By rich chromium mud oven dry to its moisture content, be 1%, after pulverizing by ball mill, rich chromium mud, sodium hydroxide and sodium carbonate mixed by following part by weight, standby;
Rich chromium mud: chromium hydroxide: sodium carbonate=10:1:1;
(2) prepare vitamin k4 oxidation solution:
Get chromium hydroxide and be crushed to 20 orders, chromium hydroxide powder after pulverizing is added and is placed in retort furnace aerobic roasting under the condition of 400 ℃, then roasting material is carried out to circulating leaching, after filtration, in filtrate, add sulfuric acid, the add-on of described sulfuric acid is 10 times of chromium hydroxide powder weight, obtains vitamin k4 oxidation solution;
(3) vitamin k4 preparation:
In there-necked flask, add methylnaphthalene, water, emulsifying agent, the weight ratio of methylnaphthalene, water and emulsifying agent is 1:5:1, then start to use oxidation solution drop reaction, control 40 ℃ of temperature, controlling titration time is 2 hours, and reaction finishes rear filtration, and washing leaching cake, filter cake is vitamin k4, after filtrate collection for the preparation of chrome tanning agent;
(4) chrome tanning agent preparation:
In above-mentioned filtrate, adding reductive agent, is trivalent chromium by sexavalent chrome Restore All wherein, adjusts basicity, and still aging 4-20h, obtains chrome tanning agent.
Above-mentioned rich chromium mud is that tannery's chrome tanning process produces the hazardous solid waste that waste water produces through alkali precipitation technology, and the butt effective constituent of described rich chromium mud is chromium hydroxide, protein.
Above-mentioned reductive agent is low molecule organic matter glucose.
Embodiment 3
Rich chromium mud is prepared a method for vitamin k4 coproduction chrome tanning agent, and the method comprises following step:
(1) rich chromium mud pretreatment:
By rich chromium mud oven dry to its moisture content, be 5%, after pulverizing by ball mill, rich chromium mud, sodium hydroxide and sodium carbonate mixed by following part by weight, standby;
Rich chromium mud: chromium hydroxide: sodium carbonate=30:5:10;
(2) prepare vitamin k4 oxidation solution:
Get chromium hydroxide and be crushed to 60 orders, chromium hydroxide powder after pulverizing is added and is placed in retort furnace aerobic roasting under the condition of 600 ℃, then roasting material is carried out to circulating leaching, after filtration, in filtrate, add sulfuric acid, the add-on of sulfuric acid is 30 times of chromium hydroxide powder weight, obtains vitamin k4 oxidation solution;
(3) vitamin k4 preparation:
In there-necked flask, add methylnaphthalene, water, emulsifying agent, the weight ratio of methylnaphthalene, water and emulsifying agent is 3:40:4, then start to use oxidation solution drop reaction, control temperature 70 C, controlling titration time is 5 hours, and reaction finishes rear filtration, and washing leaching cake, filter cake is vitamin k4, after filtrate collection for the preparation of chrome tanning agent;
(4) chrome tanning agent preparation:
In above-mentioned filtrate, adding reductive agent, is trivalent chromium by sexavalent chrome Restore All wherein, adjusts basicity, and still aging 4-20h, obtains chrome tanning agent.
Rich chromium mud is that tannery's chrome tanning process produces the hazardous solid waste that waste water produces through alkali precipitation technology, and the butt effective constituent of described rich chromium mud is chromium hydroxide, protein.
Reductive agent is burnt sodium.
Claims (9)
1. rich chromium mud is prepared a method for vitamin k4 coproduction chrome tanning agent, it is characterized in that, described method comprises following step:
(1) rich chromium mud pretreatment:
By rich chromium mud oven dry to its moisture content, be 1-5%, after pulverizing by ball mill, rich chromium mud, sodium hydroxide and sodium carbonate mixed by following part by weight, standby;
Rich chromium mud: chromium hydroxide: sodium carbonate=1-30:1-5:1-10;
(2) prepare vitamin k4 oxidation solution:
Get chromium hydroxide and be crushed to 20-60 order, chromium hydroxide powder after pulverizing is added and is placed in retort furnace aerobic roasting under the condition of 400-600 ℃, then roasting material is carried out to circulating leaching, after filtration, in filtrate, add sulfuric acid, the add-on of described sulfuric acid is 10-30 times of chromium hydroxide powder weight, obtains vitamin k4 oxidation solution;
(3) vitamin k4 preparation:
In there-necked flask, add methylnaphthalene, water, emulsifying agent, the weight ratio of methylnaphthalene, water and emulsifying agent is 1-3:5-40:1-4, then start to use oxidation solution drop reaction, control temperature 40-70 ℃, control titration time is 2-5 hour, and reaction finishes rear filtration, and washing leaching cake, filter cake is vitamin k4, after filtrate collection for the preparation of chrome tanning agent;
(4) chrome tanning agent preparation:
In above-mentioned filtrate, adding reductive agent, is trivalent chromium by sexavalent chrome Restore All wherein, adjusts basicity, and still aging 4-20h, obtains chrome tanning agent.
2. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, it is characterized in that, described rich chromium mud is that tannery's chrome tanning process produces the hazardous solid waste that waste water produces through alkali precipitation technology, and the butt effective constituent of described rich chromium mud is chromium hydroxide, protein.
3. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, and described reductive agent is low molecule organic matter or inorganics, and described low molecule organic matter is any in glucose, molasses, starch; Described inorganics is sulfurous gas, burnt sodium.
4. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, it is characterized in that described rich chromium mud: chromium hydroxide: the ratio of weight and number of sodium carbonate is 25:2:2.
5. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, it is characterized in that, described step is crushed to 40 orders by chromium hydroxide in (2).
6. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, it is characterized in that, the add-on of the middle sulfuric acid of described step (2) is 20 times of chromium hydroxide powder weight.
7. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, it is characterized in that, in the preparation of described step (3) vitamin k4:
In there-necked flask, add methylnaphthalene, water, emulsifying agent, the weight ratio of methylnaphthalene, water and emulsifying agent is 2:30:3, then start to use oxidation solution drop reaction, control temperature 60 C, controlling titration time is 3 hours, and reaction finishes rear filtration, and washing leaching cake, filter cake is vitamin k4, after filtrate collection for the preparation of chrome tanning agent.
8. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, it is characterized in that, and in described step (1), by rich chromium mud oven dry to its moisture content, be 2%.
9. a kind of rich chromium mud according to claim 1 is prepared the method for vitamin k4 coproduction chrome tanning agent, it is characterized in that, in described step (4), the still aging time is 8 hours.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310729810.6A CN103694097B (en) | 2013-12-26 | 2013-12-26 | A kind ofly rich chromium mud is utilized to prepare the method for vitamin k4 coproduction chrome tanning agent |
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| CN201310729810.6A CN103694097B (en) | 2013-12-26 | 2013-12-26 | A kind ofly rich chromium mud is utilized to prepare the method for vitamin k4 coproduction chrome tanning agent |
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| CN103694097B CN103694097B (en) | 2016-01-20 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101333007A (en) * | 2008-08-07 | 2008-12-31 | 浙江工商大学 | Method for recovering sodium dichromate form chromium-containing electroplating sludge |
| CN101348425A (en) * | 2008-09-02 | 2009-01-21 | 山东大华广济生化工程有限公司 | Method for coproduction of chrome tanning agent and menadione |
| CN103352092A (en) * | 2012-12-24 | 2013-10-16 | 山东华升化工科技有限公司 | Method for preparation of chrome tanning agent and combined production of vitamin K3 through using chromium-rich sludge |
| CN103449522A (en) * | 2012-06-01 | 2013-12-18 | 中国科学院过程工程研究所 | Method for producing chromates through using chromium-containing waste residues |
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2013
- 2013-12-26 CN CN201310729810.6A patent/CN103694097B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101333007A (en) * | 2008-08-07 | 2008-12-31 | 浙江工商大学 | Method for recovering sodium dichromate form chromium-containing electroplating sludge |
| CN101348425A (en) * | 2008-09-02 | 2009-01-21 | 山东大华广济生化工程有限公司 | Method for coproduction of chrome tanning agent and menadione |
| CN103449522A (en) * | 2012-06-01 | 2013-12-18 | 中国科学院过程工程研究所 | Method for producing chromates through using chromium-containing waste residues |
| CN103352092A (en) * | 2012-12-24 | 2013-10-16 | 山东华升化工科技有限公司 | Method for preparation of chrome tanning agent and combined production of vitamin K3 through using chromium-rich sludge |
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| CN103694097B (en) | 2016-01-20 |
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