CN109232404A - A kind of preparation method of chromium picolinate - Google Patents
A kind of preparation method of chromium picolinate Download PDFInfo
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- CN109232404A CN109232404A CN201810928688.8A CN201810928688A CN109232404A CN 109232404 A CN109232404 A CN 109232404A CN 201810928688 A CN201810928688 A CN 201810928688A CN 109232404 A CN109232404 A CN 109232404A
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- Prior art keywords
- picoline
- temperature
- chromium
- chromium picolinate
- oxidation reaction
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D213/78—Carbon atoms having three bonds to hetero atoms, with at the most one bond to halogen, e.g. ester or nitrile radicals
- C07D213/79—Acids; Esters
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D213/00—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members
- C07D213/02—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members
- C07D213/04—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom
- C07D213/60—Heterocyclic compounds containing six-membered rings, not condensed with other rings, with one nitrogen atom as the only ring hetero atom and three or more double bonds between ring members or between ring members and non-ring members having three double bonds between ring members or between ring members and non-ring members having no bond between the ring nitrogen atom and a non-ring member or having only hydrogen or carbon atoms directly attached to the ring nitrogen atom with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D213/78—Carbon atoms having three bonds to hetero atoms, with at the most one bond to halogen, e.g. ester or nitrile radicals
- C07D213/79—Acids; Esters
- C07D213/803—Processes of preparation
- C07D213/807—Processes of preparation by oxidation of pyridines or condensed pyridines
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Pyridine Compounds (AREA)
Abstract
The invention discloses a kind of preparation methods of chromium picolinate, it is the 2- picoline of 1.1~1.3:3.0:3.0~5.0: oxidant including taking mass ratio: water mixing, pH value is adjusted to 4.5~6.0, carry out oxidation reaction, the temperature of oxidation reaction is 200~240 DEG C, the pressure of oxidation reaction is 2.5~4.2MPa, and the time of oxidation reaction is 1~10h；Then lowered temperature reclamation 2- picoline again adjusts pH value to 2.0~3.0 again, carries out complex reaction under normal pressure, the temperature of complex reaction is 85~90 DEG C, and the time of complex reaction is 1~5h；Last decrease temperature crystalline, centrifugation, washing, dry obtained chromium picolinate.The present invention is using 2- picoline as starting material, 2- picoline is oxidized to by 2- pyridine carboxylic acid by aqueous oxidizing agent solution through high temperature and high pressure in acid condition, oxidant is then reduced to chromium sulfate basic, then 2- pyridine carboxylic acid and chromium sulfate basic are complexed as chromium picolinate under normal pressure, preparation methods steps are simple, product yield is high, has many advantages, such as green, environmentally friendly, at low cost.
Description
Technical field
The present invention relates to chromium picolinate technical fields, and in particular to a kind of preparation method of chromium picolinate.
Background technique
With the research and development to chromium, the mankind have realized that chromium is micro elements needed by human.At present chromium there are valences
State includes Cr2+、Cr3+And Cr6+, Cr3+It is chromium existing stable form in human body, compound participates in bone formation and albumen
The biochemical process of matter, fat, glycometabolism and insulin has facilitation to hemoglobin synthesis and hematopoiesis.But Cr6+
The metabolism that sugar, fat and the big substance of protein three are then influenced in human body, inhibits the activity of glutathione reductase, is formed with oxygen
Chromium oxide captures partial oxidation in blood, leads to body anoxic, causes dysbolism.
Chromium source is divided into inorganic chromium and Organic Chromium, and inorganic chromium (such as chromium sulfate, chromium trichloride) bioactivity is very low, biology
Utilization rate 0.4%~3% or so, the bioavailability of Organic Chromium are 10 times of inorganic chromium or more, and bioavailability is up to 10%
~25%.At present, it is considered to be the best benefit Chroma-Pak of the mankind is chromium picolinate, chromium picolinate (Chromium
Picolinate it) is also known as chromium picolinate, picolinic acid chromium is 2- pyridine carboxylic acid and Cr3+The complex compound of compound, molecular formula are
Cr(C6H4NO2)3, molecular weight 418.33 is burgundy crystals fine powder, good fluidity, is stablized under room temperature, slightly soluble
Yu Shui does not dissolve in ethyl alcohol, belongs to fat-soluble non-electrolyte, can pass through cell membrane and directly act on tissue.
Currently, there are three types of the techniques of pyridine synthesis chromic formate: 1, using 2- picoline as raw material, through potassium permanganate or weight chromium
Sour potassium and chromic anhybride etc. are oxidizing to obtain 2- pyridine carboxylic acid, adds trivalent chromium and is complexed to obtain 2- chromium picolinate.As specially
A kind of synthetic method and patent No. CN102875458B of 2- chromium picolinate disclosed in the patent of invention of benefit CN1772737A
Patent of invention disclosed in a kind of synthetic method of 2- chromium picolinate.The above method is also easy to produce a large amount of oxygen in process of production
Change the chromyl chrome green of by-product-(or chromium hydroxide) and the manganese dioxide waste residues containing manganese, and need to mistake in process
Subsequent complex reaction is carried out after filtering out again, there are cumbersome, the dangerous waste processing of giving up containing chromium is difficult.
2, using 2- vinylpyridine as raw material, 2- pyridine carboxylic acid is obtained through potassium permanganate oxidation, trivalent chromium is added and is complexed
To 2- chromium picolinate.The chromium picolinate synthesis technology disclosed such as the patent of invention of patent No. CN1408708A.The technique
In the resource scarcity of 2- vinylpyridine raw material and expensive, be unfavorable for mass production.
3, using 2- cyanopyridine as starting material, water is solvent, and sodium hydroxide is added and is hydrolyzed, and hydrolysis, which finishes, adjusts pH
Value is 3.5~5.5, and chromium chloride is added to be complexed to obtain product.The 2- pyridine as disclosed in the patent of invention of patent No. CN101602716B
One-step method disclosed in the synthetic method of chromic formate, the patent of invention of patent No. CN103319401A prepares the work of 2- chromium picolinate
A kind of synthetic method and the patent No. of chromium picolinate disclosed in skill, the patent of invention of patent No. CN103833628B
A kind of method of direct-reduction process pyridine synthesis chromic formate disclosed in the patent of invention of CN105541707A.Because of 2- cyanogen in this method
Yl pyridines fusing point is high and not soluble in water, therefore hydrolysis, in heterogeneous middle progress, the reaction time is long, while generating after hydrolyzing a large amount of
Ammonia needs absorption to handle, and the waste containing ammonia generated will cause pollution to environment, bring huge pressure to environmental protection.
Summary of the invention
That the purpose of the present invention is to provide a kind of processing steps is simple, raw material is cheap and easy to get and production process is environmentally protective,
It is suitble to the industrial production process of the chromium picolinate of industrialized production.
The purpose of the present invention is what is be achieved through the following technical solutions:
A kind of preparation method of chromium picolinate is the 2- methyl of 1.1~1.3:3.0:3.0~5.0 including taking mass ratio
Pyridine: oxidant: water mixing adjusts pH value to 4.5~6.0, carries out oxidation reaction, the temperature of oxidation reaction is 200~240
DEG C, the pressure of oxidation reaction is 2.5~4.2MPa, and the time of oxidation reaction is 1~10h；Then lowered temperature reclamation 2- picoline
PH value is adjusted afterwards to 2.0~3.0, carries out complex reaction under normal pressure, the temperature of complex reaction is 85~90 DEG C, complex reaction
Time is 1~5h；Last decrease temperature crystalline, centrifugation, washing, dry obtained chromium picolinate.
Further, the adjusting pH value is by the combination of one or more of addition sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid
It realizes.
Further, the oxidant is sodium dichromate, potassium bichromate, ammonium dichromate, sodium chromate, potassium chromate, chromic anhybride
One or more of combination.
Oxidant of the invention passes through the specific chemical equation of sulphur acid for adjusting pH value using sodium dichromate simultaneously:
The invention has the following advantages:
(1) using 2- picoline as starting material, pass through oxidant (such as dichromic acid through high temperature and high pressure in acid condition
Sodium) 2- picoline is oxidized to 2- pyridine carboxylic acid by aqueous solution, it is reduced to chromium sulfate basic if oxidant (such as sodium dichromate),
Then 2- pyridine carboxylic acid and chromium sulfate basic are complexed as chromium picolinate under normal pressure, the preparation method step is simple, product
High income, compared with traditional potassium permanganate oxidation complexometry and 2- cyanopyridine hydrolysis complexometry, without dangerous solid waste manganese dioxide
It is generated with ammonia-contaminated gas, is the Preparation Method of Pyridinecarboxylic Acid of the green for being really suitble to industrialized production, environmental protection, economy；
(2) cheap and from a wealth of sources using 2- picoline as starting material, production cost is low, raw material sources not
It is limited；
(3) by 2- picoline, oxidant (such as sodium dichromate), water according to mass ratio be 1.1~1.3:3.0:3.0~
5.0 mixing, proportion science, content of 6-valence Cr ions reacts remaining 2- in 1ppm hereinafter, without additional addition reducing agent after reaction
Picoline can make next raw materials for production after being distilled to recover；And oxidant (such as sodium dichromate) reduzate is alkali formula sulfuric acid
Chromium directly can carry out complex reaction with 2- pyridine carboxylic acid, without additionally using trivalent chromium；Shorten process flow and reduction is produced into
This.
Detailed description of the invention
Fig. 1 is process flow chart of the invention.
Specific embodiment
Embodiment 1
As shown in Figure 1, the preparation method of chromium picolinate provided in this embodiment includes the following steps:
(1) it takes the 2- picoline, the sodium dichromate of 246kg and the water of 400kg of 80kg to be put into reaction kettle, sulfuric acid is added
PH value is adjusted to 4.5~5.0, then heating makes 200~210 DEG C of temperature, pressure in reaction kettle be 2.5~3.2MPa, protects
Warm pressure maintaining oxidation reaction 1h；
(2) temperature in reaction kettle is down to 85~90 DEG C, vacuum distillation, distillate is 2- picoline aqueous solution, should
2- picoline aqueous solution can be used as the raw material of production next time；
(3) into the reaction kettle after being evaporated under reduced pressure plus sulfuric acid, adjust pH value to 2.0~2.5, and keep temperature be 85~
90 DEG C, complex reaction 5h, is then cooled to 20~30 DEG C and is crystallized under normal pressure, finally centrifugation, 50kg water washing, dry system
Obtain 126.2kg chromium picolinate.
Embodiment 2
The preparation method of chromium picolinate provided in this embodiment includes the following steps:
(1) it takes the 2- picoline, the potassium bichromate of 246kg and the water of 400kg of 100kg to be put into reaction kettle, salt is added
Acid for adjusting pH value is to 5.0~5.5, and then heating makes 210~230 DEG C of temperature, pressure in reaction kettle be 2.2~3.2MPa,
Heat-insulation pressure keeping oxidation reaction 10h；
(2) temperature in reaction kettle is down to 85~90 DEG C, vacuum distillation, distillate is 2- picoline aqueous solution, should
2- picoline aqueous solution can be used as the raw material of production next time；
(3) into the reaction kettle after being evaporated under reduced pressure plus hydrochloric acid, adjust pH value to 2.5~3.0, and keep temperature be 85~
90 DEG C, complex reaction 1h, is then cooled to 20~30 DEG C and is crystallized under normal pressure, finally centrifugation, 50kg water washing, dry system
Obtain 120.6kg chromium picolinate.
Embodiment 3
The preparation method of chromium picolinate provided in this embodiment includes the following steps:
(1) it takes the 2- picoline, the ammonium dichromate of 246kg and the water of 400kg of 100kg to be put into reaction kettle, phosphorus is added
Acid for adjusting pH value is to 5.0~5.5, and then heating makes 230~240 DEG C of temperature, pressure in reaction kettle be 3.2~3.5MPa,
Heat-insulation pressure keeping oxidation reaction 6h；
(2) temperature in reaction kettle is down to 85~90 DEG C, vacuum distillation, distillate is 2- picoline aqueous solution, should
2- picoline aqueous solution can be used as the raw material of production next time；
(3) into the reaction kettle after being evaporated under reduced pressure plus phosphoric acid, adjust pH value to 2.0~3.0, and keep temperature be 85~
90 DEG C, complex reaction 1h, is then cooled to 20~30 DEG C and is crystallized under normal pressure, finally centrifugation, 50kg water washing, dry system
Obtain 132.8kg chromium picolinate.
Embodiment 4
The preparation method of chromium picolinate provided in this embodiment includes the following steps:
(1) it takes the 2- picoline, the sodium chromate of 246kg and the water of 500kg of 100kg to be put into reaction kettle, nitric acid is added
PH value is adjusted to 5.0~5.5, then heating makes 230~240 DEG C of temperature, pressure in reaction kettle be 3.5~4.2MPa, protects
Warm pressure maintaining oxidation reaction 1h；
(2) temperature in reaction kettle is down to 85~90 DEG C, vacuum distillation, distillate is 2- picoline aqueous solution, should
2- picoline aqueous solution can be used as the raw material of production next time；
(3) into the reaction kettle after being evaporated under reduced pressure plus nitric acid, adjust pH value to 2.0~3.0, and keep temperature be 85~
90 DEG C, complex reaction 1h, is then cooled to 20~30 DEG C and is crystallized under normal pressure, finally centrifugation, 50kg water washing, dry system
Obtain 136.2kg chromium picolinate.
Chromium picolinate obtained by Examples 1 to 4 is subjected to Cr VI detection, does not find the presence of Cr VI.
The above is only the preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto, any
The transformation and replacement that are carried out based on technical solution provided by the present invention and inventive concept should all cover the protection scope in invention
It is interior.Especially, adjusting reagent used in pH value can also be used the reagent realization of other adjustable pH value, not only this implementation
Sulfuric acid, the nitric acid, hydrochloric acid, phosphoric acid of example offer.
Claims (3)
1. a kind of preparation method of chromium picolinate, characterized by comprising: taking mass ratio is 1.1~1.3:3.0:3.0~5.0
2- picoline: oxidant: water mixing adjusts pH value to 4.5~6.0, carries out oxidation reaction, and the temperature of oxidation reaction is
200~240 DEG C, the pressure of oxidation reaction is 2.5~4.2MPa, and the time of oxidation reaction is 1~10h；Then lowered temperature reclamation 2-
PH value is adjusted after picoline to 2.0~3.0, carries out complex reaction under normal pressure, the temperature of complex reaction is 85~90 DEG C, network
The time for closing reaction is 1~5h；Last decrease temperature crystalline, centrifugation, washing, dry obtained chromium picolinate.
2. the preparation method of chromium picolinate according to claim 1, it is characterised in that: the adjusting pH value is by adding
The combination of one or more of sulfuric acid, nitric acid, hydrochloric acid, phosphoric acid is added to realize.
3. the preparation method of chromium picolinate according to claim 1, it is characterised in that: the oxidant is dichromic acid
The combination of one or more of sodium, potassium bichromate, ammonium dichromate, sodium chromate, potassium chromate, chromic anhybride.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810928688.8A CN109232404A (en) | 2018-08-15 | 2018-08-15 | A kind of preparation method of chromium picolinate |
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| CN201810928688.8A CN109232404A (en) | 2018-08-15 | 2018-08-15 | A kind of preparation method of chromium picolinate |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116332842A (en) * | 2023-01-31 | 2023-06-27 | 四川新一美生物科技有限公司 | Preparation method for co-production of 2-chromium picolinate and chromium propionate |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4117217A (en) * | 1976-06-10 | 1978-09-26 | Chemplex Company | Method of polymerizing olefins |
| US5087623A (en) * | 1988-05-31 | 1992-02-11 | Nitrition 21 | Chromic picolinate treatment |
| US5677461A (en) * | 1995-04-13 | 1997-10-14 | Republic Of Korea Represented By Rural Development Administration | Method for producing chromium picolinate complex |
| KR0184380B1 (en) * | 1995-12-19 | 1999-05-15 | 김은영 | Method for preparing picoline acid chronium |
| CN1772737A (en) * | 2005-09-30 | 2006-05-17 | 中国科学院山西煤炭化学研究所 | Synthesis process of chronium 2-picolinate |
| CN102875458A (en) * | 2012-10-24 | 2013-01-16 | 北京桑普生物化学技术有限公司 | Synthesis method of chromium 2-pyridylformate |
| CN105541707A (en) * | 2016-01-28 | 2016-05-04 | 四川尚元精细化工有限责任公司 | Method for synthesizing chromium picolinate with direct reduction process |
| CN106349155A (en) * | 2015-07-17 | 2017-01-25 | 唐翔 | Process for preparing chromium picolinate from ferrochromium |
-
2018
- 2018-08-15 CN CN201810928688.8A patent/CN109232404A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4117217A (en) * | 1976-06-10 | 1978-09-26 | Chemplex Company | Method of polymerizing olefins |
| US5087623A (en) * | 1988-05-31 | 1992-02-11 | Nitrition 21 | Chromic picolinate treatment |
| US5677461A (en) * | 1995-04-13 | 1997-10-14 | Republic Of Korea Represented By Rural Development Administration | Method for producing chromium picolinate complex |
| KR0184380B1 (en) * | 1995-12-19 | 1999-05-15 | 김은영 | Method for preparing picoline acid chronium |
| CN1772737A (en) * | 2005-09-30 | 2006-05-17 | 中国科学院山西煤炭化学研究所 | Synthesis process of chronium 2-picolinate |
| CN102875458A (en) * | 2012-10-24 | 2013-01-16 | 北京桑普生物化学技术有限公司 | Synthesis method of chromium 2-pyridylformate |
| CN106349155A (en) * | 2015-07-17 | 2017-01-25 | 唐翔 | Process for preparing chromium picolinate from ferrochromium |
| CN105541707A (en) * | 2016-01-28 | 2016-05-04 | 四川尚元精细化工有限责任公司 | Method for synthesizing chromium picolinate with direct reduction process |
Non-Patent Citations (1)
| Title |
|---|
| 马世昌主编: "《化学物质辞典》", 30 April 1999, 陕西科学技术出版社 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116332842A (en) * | 2023-01-31 | 2023-06-27 | 四川新一美生物科技有限公司 | Preparation method for co-production of 2-chromium picolinate and chromium propionate |
| CN116332842B (en) * | 2023-01-31 | 2023-10-27 | 四川新一美生物科技有限公司 | Preparation method for co-production of 2-chromium picolinate and chromium propionate |
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