CN105418411A - Preparation method for easily soluble calcium hydrogen citrate - Google Patents
Preparation method for easily soluble calcium hydrogen citrate Download PDFInfo
- Publication number
- CN105418411A CN105418411A CN201510969567.4A CN201510969567A CN105418411A CN 105418411 A CN105418411 A CN 105418411A CN 201510969567 A CN201510969567 A CN 201510969567A CN 105418411 A CN105418411 A CN 105418411A
- Authority
- CN
- China
- Prior art keywords
- calcium hydrogen
- hydrogen citrate
- limestone powder
- crystallization
- slurries
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/41—Preparation of salts of carboxylic acids
- C07C51/412—Preparation of salts of carboxylic acids by conversion of the acids, their salts, esters or anhydrides with the same carboxylic acid part
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/43—Separation; Purification; Stabilisation; Use of additives by change of the physical state, e.g. crystallisation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
- C07C51/487—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to chemical modification
Abstract
The invention belongs to the field of chemical engineering, particularly a preparation method for easily soluble calcium hydrogen citrate. The easily soluble calcium hydrogen citrate crystals are mainly prepared through the steps of: performing a reaction on limestone powder and a fermented clean liquid of citric acid; performing filtration and crystallization; and then performing neutralizing and crystallizing processes for continuously three times. Moreover, the obtained calcium hydrogen citrate crystals are large and uniform in grain, and the purity is far higher than that of conventional calcium citrate crystals, and the solubility is higher than that of common calcium hydrogen citrate.
Description
Technical field
The invention belongs to chemical field, be specifically related to a kind of preparation method of easy molten calcium hydrogen citrate.
Background technology
Calcium hydrogen citrate, molecular formula is Ca
2(C
6h
6o
7)
23H
2o is white particle or white powder crystal, and usually containing 3 crystal water, relative molecular mass is 514.42.Odorless, is slightly soluble in water.Calcium is the fifth-largest element in human body, and it all plays a very important role the many physiological processs in human body.In the tooth of the mankind and bone, 99% is calcium.Therefore, no matter be that trophicity or the calcium deficiency of metabolic all can have extremely wide negative impact to the health of human body.At present, on market, calcium supplementing product is as calcium chloride, calcium carbonate, calcium phosphate, calcium acetate, calglucon, calcium lactate etc., all there is disadvantage to a certain degree.Calcium hydrogen citrate is the utilization that also can directly be absorbed by the body when not having hydrochloric acid in gastric juice, can not stimulate enteron aisle.Calcium hydrogen citrate also has higher specific absorption and bioavailability, can not cause the side effects such as constipation after taking.The generation of urinary stone disease can also be suppressed, this is because after calcium hydrogen citrate absorbed, can discharge calcium ion in vivo, the calcium ion in caoxalate, calcium urate, calcium phosphate then cements out by citrate ion in urine, forming citrate of lime gets rid of external, thus decreases the possibility of urinary stone disease.
Very high to the purity requirement of calcium carbonate or calcium hydroxide in the method for existing production calcium hydrogen citrate, thus cause cost high.When using limestone powder for raw material, due to the calcium carbonate content 90-99% of limestone powder, therefore the ratio that solution mesosilicic acid salt accounts for calcium hydrogen citrate crystal reaches 0.5-2.5%, account for the 0.5-4 ‰ of solution, therefore the impurity do not removed in limestone powder can be larger on quality product impact, simultaneously impurity is very large on the impact of citric acid byproduct calcium sulfate, makes calcium sulfate cannot deep processing.
Present invention reduces the impact on quality product and byproduct calcium sulfate quality such as silicate impurity that limestone powder purity defect brings, remove most oxalic acid simultaneously, achieve the method that low-grade limestone powder prepares higher-grade calcium hydrogen citrate, and it is higher to obtain calcium hydrogen citrate solubleness.
Summary of the invention
In order to overcome defect of the prior art, the invention provides a kind of preparation method of easy molten calcium hydrogen citrate, by the mode of multistage crystallization, improving the shortcoming that traditional calcium hydrogen citrate solubleness is little, developing a kind of new production technology.
For achieving the above object, the technical solution used in the present invention is as follows:
A preparation method for easy molten calcium hydrogen citrate, concrete steps are as follows:
(1) in first degree crystalline tank, citric acid fermentation aqueous solution and limestone powder are carried out mixing replacement(metathesis)reaction occurs, obtain calcium hydrogen citrate slurries.In order to ensure can to react between citric acid in slurries and limestone powder slurries, and reaction carries out towards the direction generating calcium hydrogen citrate, need by regulating the flow of slurries and limestone powder slurries to ensure that the mol ratio of citric acid molecule and calcium ion in whole reaction system is 1:0.65-0.85;
(2) citric acid fermentation aqueous solution after filtering is added in the slurries that step (1) obtains carry out upper strata backflow, first degree crystalline is carried out to the slurries of the calcium hydrogen citrate obtained.Generate in order to ensure the direction of product to calcium hydrogen citrate, and be beneficial to the crystallization of calcium hydrogen citrate crystal, need the pH value controlling whole system to be 2.8-3.2, Tc is 70-90 DEG C, and crystallization time is 2-4h.The adjustment of pH value can realize by adding citric acid fermentation aqueous solution.For ensure calcium hydrogen citrate can fully with citric acid reactions in fermented liquid, require that fermentation clear liquid acidity should be too not low, it is beneficial that acidity maintains 11-14%, and fermentation clear liquid color should be excessively not dark, otherwise affects calcium salt quality;
(3) by the magma overflow after first degree crystalline to secondary crystallization tank, and wherein slowly stream add limestone powder slurries, carry out in secondary and crystallization.In this process, limestone powder slurries and citric acid or dihydrogen citrate calcium react and are converted into calcium hydrogen citrate, from and the supersaturated solution that defines containing calcium hydrogen citrate, under the induction of calcium hydrogen citrate crystal seed, degree of supersaturation is released again further, realizes the further growth of calcium hydrogen citrate;
(4) by the magma overflow to three grade in secondary and after crystallization and crystallizer, and wherein slowly stream add limestone powder slurries, carry out in three grades and crystallization.In like manner, in this process, limestone powder slurries and citric acid or dihydrogen citrate calcium react and are converted into calcium hydrogen citrate, from and the supersaturated solution that defines containing calcium hydrogen citrate, under the induction of calcium hydrogen citrate crystal seed, degree of supersaturation is released again further, realizes the further growth of calcium hydrogen citrate;
(5) magma in final and after crystallization is flowed into slurry tank, upper strata calcium hydrogen citrate backflow of particles, to first degree crystalline process, adds ethanol in lower floor's calcium hydrogen citrate crystal, makes reaction ripe.
(6) by the calcium hydrogen citrate crystal drying and packaging of the maturation of step (5) gained.
It is 65-85 DEG C that citric acid fermentation aqueous solution described in step (1) and limestone powder carry out hybrid reaction temperature, and the reaction times is 2-4h, and in whole reaction system, the mol ratio of citric acid molecule and calcium ion is 1:0.65-0.85.
Fermentation clear liquid after filtration described in step (2) and calcium hydrogen citrate slurry volume are than being 1:0.1-0.3, and the pH value controlling whole system is 2.8-3.2, and Tc is 70-90 DEG C, and crystallization time is 2-4h.
Tc described in step (3) is 70-90 DEG C, system pH is 3.0-3.4, and crystallization time is 3-6h; In limestone powder used in described limestone powder slurries, calcium carbonate mass content is 97-99%, and its particle is less than 100 orders, and in limestone powder slurries, solid masses content is 50%-60%.
Tc described in step (4) is 70-90 DEG C, and pH value is 3.5-4.5, and crystallization time is 2-6h; In limestone powder used in described limestone powder slurries, calcium carbonate mass content is 97-99%, and its particle is less than 100 orders, and in limestone powder slurries, solid masses content is 50%-60%.
The present invention mainly shortens the reaction times of citric acid to calcium hydrogen citrate, then the supersaturated solution of calcium hydrogen citrate is provided to realize the continuous crystallisation of calcium hydrogen citrate by multistage neutralization reaction, extend the crystallization time of calcium hydrogen citrate, achieve the sufficient crystallising of calcium hydrogen citrate.And present invention reduces the impact on quality product and byproduct calcium sulfate quality such as silicate impurity that limestone powder purity defect brings, remove most oxalic acid simultaneously, achieve the method that low-grade limestone powder prepares higher-grade calcium hydrogen citrate.Adopt the present invention to prepare hydrogen citrate mother liquor of calcium and return throwing rate decline about 50%, the calcium hydrogen citrate crystal grain obtained is large and evenly, purity is far away higher than traditional calcium hydrogen citrate, and solubleness comparatively usual way acquisition calcium hydrogen citrate is high.
For ensure citrate of lime can fully with citric acid reactions in fermented liquid, require that fermentation clear liquid acidity should be too not low, it is beneficial that acidity maintains between 11-14%, and fermentation clear liquid color should be excessively not dark, otherwise affects calcium salt quality.
Find in actual experiment, the speed of response that citrate of lime and citric acid reactions generate calcium hydrogen citrate is slow, and reaction is not thorough, should be not less than 75 DEG C for improving speed of response temperature of reaction.
Reflux ratio is also one of important parameter controlled in reaction, long owing to reacting required time itself, the time existed in tank is maintained short material three grades, reflux line is added so maintain between tank and first class reaction pot at three grades, control backflow and discharging ratio are between 3:1-4:1, and the reaction times not only extending material accelerates the flowing of material in tank at different levels simultaneously.
In the process of reaction, the moment monitors the pH value change of the material in tank at different levels. and judge whether reaction completes, and whether notifies next procedure blowing by the PH monitored in tank at different levels, thus the inspection of PH is absolutely necessary a link.
Figure of description
Fig. 1 is the process flow sheet of a kind of preparation method of easy molten calcium hydrogen citrate;
Embodiment:
Embodiment 1
A preparation method for easy molten calcium hydrogen citrate, the steps include:
(1) citric acid fermentation aqueous solution and limestone powder are carried out hybrid reaction, hybrid reaction temperature is 65 DEG C, and the reaction times is 2h, and in whole reaction system, the mol ratio of citric acid molecule and calcium ion is 1:0.65;
(2) citric acid fermentation aqueous solution after filtering is added in the slurries that step (1) obtains carry out upper strata backflow, first degree crystalline is carried out to the slurries of the calcium hydrogen citrate obtained, fermentation clear liquid is 1:0.1 with the calcium hydrogen citrate slurry volume ratio of backflow, the pH value controlling whole system is 2.8, Tc is 70 DEG C, and crystallization time is 2h;
(3) by the magma overflow after first degree crystalline to secondary crystallization tank, and wherein slowly stream add limestone powder slurries, carry out in secondary and crystallization, Tc is 70 DEG C, and system pH is 3.0, and crystallization time is 3h;
(4) by the magma overflow to three grade in secondary and after crystallization and crystallizer, and wherein slowly stream add limestone powder slurries, carry out in three grades and crystallization, described Tc is 70 DEG C, and pH value is 3.5, and crystallization time is 2h;
(5) magma in final and after crystallization is flowed into slurry tank, upper strata calcium hydrogen citrate backflow of particles, to first degree crystalline process, adds ethanol in lower floor's calcium hydrogen citrate crystal, makes reaction ripe.
(6) by gained calcium hydrogen citrate crystal drying and packaging.
Embodiment 2
The preparation method of easy molten calcium hydrogen citrate, the steps include:
(1) citric acid fermentation aqueous solution and limestone powder are carried out hybrid reaction, hybrid reaction temperature is 85 DEG C, and the reaction times is 4h, and in whole reaction system, the mol ratio of citric acid molecule and calcium ion is 1:0.85;
(2) citric acid fermentation aqueous solution after filtering is added in the slurries that step (1) obtains carry out upper strata backflow, first degree crystalline is carried out to the slurries of the calcium hydrogen citrate obtained, fermentation clear liquid is 1:0.3 with the calcium hydrogen citrate slurry volume ratio of backflow, the pH value controlling whole system is 3.2, Tc is 90 DEG C, and crystallization time is 4h;
(3) by the magma overflow after first degree crystalline to secondary crystallization tank, and wherein slowly stream add limestone powder slurries, carry out in secondary and crystallization, Tc is 90 DEG C, and system pH is 3.4, and crystallization time is 6h;
(4) by the magma overflow to three grade in secondary and after crystallization and crystallizer, and wherein slowly stream add limestone powder slurries, carry out in three grades and crystallization, described Tc is 90 DEG C, and pH value is 4.5, and crystallization time is 6h;
(5) magma in final and after crystallization is flowed into slurry tank, upper strata calcium hydrogen citrate backflow of particles, to first degree crystalline process, adds ethanol in lower floor's calcium hydrogen citrate crystal, makes reaction ripe.
(6) by gained calcium hydrogen citrate crystal drying and packaging.
Embodiment 3
The preparation method of easy molten calcium hydrogen citrate, the steps include:
(1) citric acid fermentation aqueous solution and limestone powder are carried out hybrid reaction, hybrid reaction temperature is 75 DEG C, and the reaction times is 3h, and in whole reaction system, the mol ratio of citric acid molecule and calcium ion is 1:0.75;
(2) citric acid fermentation aqueous solution after filtering is added in the slurries that step (1) obtains carry out upper strata backflow, first degree crystalline is carried out to the slurries of the calcium hydrogen citrate obtained, fermentation clear liquid is 1:0.2 with the calcium hydrogen citrate slurry volume ratio of backflow, the pH value controlling whole system is 3.0, Tc is 80 DEG C, and crystallization time is 3h;
(3) by the magma overflow after first degree crystalline to secondary crystallization tank, and wherein slowly stream add limestone powder slurries, carry out in secondary and crystallization, Tc is 80 DEG C, and system pH is 3.2, and crystallization time is 4h;
(4) by the magma overflow to three grade in secondary and after crystallization and crystallizer, and wherein slowly stream add limestone powder slurries, carry out in three grades and crystallization, described Tc is 90 DEG C, and pH value is 4.0, and crystallization time is 3h;
(5) magma in final and after crystallization is flowed into slurry tank, upper strata calcium hydrogen citrate backflow of particles, to first degree crystalline process, adds ethanol in lower floor's calcium hydrogen citrate crystal, makes reaction ripe.
(6) by gained calcium hydrogen citrate crystal drying and packaging.
Embodiment 4
The preparation method of easy molten calcium hydrogen citrate, the steps include:
(1) citric acid fermentation aqueous solution and limestone powder are carried out hybrid reaction, hybrid reaction temperature is 65 DEG C, and the reaction times is 4h, and in whole reaction system, the mol ratio of citric acid molecule and calcium ion is 1:0.85;
(2) citric acid fermentation aqueous solution after filtering is added in the slurries that step (1) obtains carry out upper strata backflow, first degree crystalline is carried out to the slurries of the calcium hydrogen citrate obtained, fermentation clear liquid is 1:0.3 with the calcium hydrogen citrate slurry volume ratio of backflow, the pH value controlling whole system is 3.2, Tc is 80 DEG C, and crystallization time is 3h;
(3) by the magma overflow after first degree crystalline to secondary crystallization tank, and wherein slowly stream add limestone powder slurries, carry out in secondary and crystallization, Tc is 70 DEG C, and system pH is 3.2, and crystallization time is 4h;
(4) by the magma overflow to three grade in secondary and after crystallization and crystallizer, and wherein slowly stream add limestone powder slurries, carry out in three grades and crystallization, described Tc is 90 DEG C, and pH value is 4.0, and crystallization time is 6h;
(5) magma in final and after crystallization is flowed into slurry tank, upper strata calcium hydrogen citrate backflow of particles, to first degree crystalline process, adds ethanol in lower floor's calcium hydrogen citrate crystal, makes reaction ripe.
(6) by gained calcium hydrogen citrate crystal drying and packaging.
Embodiment 5
The preparation method of easy molten calcium hydrogen citrate, the steps include:
(1) citric acid fermentation aqueous solution and limestone powder are carried out hybrid reaction, hybrid reaction temperature is 85 DEG C, and the reaction times is 2h, and in whole reaction system, the mol ratio of citric acid molecule and calcium ion is 1:0.65;
(2) citric acid fermentation aqueous solution after filtering is added in the slurries that step (1) obtains carry out upper strata backflow, first degree crystalline is carried out to the slurries of the calcium hydrogen citrate obtained, fermentation clear liquid is 1:0.1 with the calcium hydrogen citrate slurry volume ratio of backflow, the pH value controlling whole system is 3.0, Tc is 90 DEG C, and crystallization time is 2h;
(3) by the magma overflow after first degree crystalline to secondary crystallization tank, and wherein slowly stream add limestone powder slurries, carry out in secondary and crystallization, Tc is 90 DEG C, and system pH is 3.4, and crystallization time is 2h;
(4) by the magma overflow to three grade in secondary and after crystallization and crystallizer, and wherein slowly stream add limestone powder slurries, carry out in three grades and crystallization, described Tc is 90 DEG C, and pH value is 4.5, and crystallization time is 3h;
(5) magma in final and after crystallization is flowed into slurry tank, upper strata calcium hydrogen citrate backflow of particles, to first degree crystalline process, adds ethanol in lower floor's calcium hydrogen citrate crystal, makes reaction ripe.
(6) by gained calcium hydrogen citrate crystal drying and packaging.
Table 1
Claims (5)
1. a preparation method for easy molten calcium hydrogen citrate, it is characterized in that, concrete steps are as follows:
(1) in first degree crystalline tank, citric acid fermentation aqueous solution and limestone powder are carried out hybrid reaction, obtain citrate of lime slurries;
(2) citric acid fermentation aqueous solution after filtering is added in the slurries that step (1) obtains carry out upper strata backflow, first degree crystalline is carried out to the slurries of the calcium hydrogen citrate obtained;
(3) by the magma overflow after first degree crystalline to secondary crystallization tank, and wherein slowly stream add limestone powder slurries, carry out in secondary and crystallization;
(4) by the magma overflow to three grade in secondary and after crystallization and crystallizer, and wherein slowly stream add limestone powder slurries, carry out in three grades and crystallization;
(5) magma in final and after crystallization is flowed into slurry tank, upper strata calcium hydrogen citrate backflow of particles, to first degree crystalline process, adds ethanol in lower floor's calcium hydrogen citrate crystal, makes reaction ripe.
(6) by the calcium hydrogen citrate crystal drying and packaging of the maturation of step (5) gained.
2. the preparation method of easy molten calcium hydrogen citrate as claimed in claim 1, it is characterized in that, it is 65-85 DEG C that citric acid fermentation aqueous solution described in step (1) and limestone powder carry out hybrid reaction temperature, reaction times is 2-4h, and in whole reaction system, the mol ratio of citric acid molecule and calcium ion is 1:0.65-0.85.
3. the preparation method of easy molten calcium hydrogen citrate as claimed in claim 1, it is characterized in that, fermentation clear liquid after filtration described in step (2) and calcium hydrogen citrate slurry volume are than being 1:0.1-0.3, the pH value controlling whole system is 2.8-3.2, Tc is 70-90 DEG C, and crystallization time is 2-4h.
4. the preparation method of easy molten calcium hydrogen citrate as claimed in claim 1, is characterized in that, the Tc described in step (3) is 70-90 DEG C, system pH is 3.0-3.4, and crystallization time is 3-6h; In limestone powder used in described limestone powder slurries, calcium carbonate mass content is 97-99%, and its particle is less than 100 orders, and in limestone powder slurries, solid masses content is 50%-60%.
5. the preparation method of easy molten calcium hydrogen citrate as claimed in claim 1, is characterized in that, the Tc described in step (4) is 70-90 DEG C, and pH value is 3.5-4.5, and crystallization time is 2-6h; In limestone powder used in described limestone powder slurries, calcium carbonate mass content is 97-99%, and its particle is less than 100 orders, and in limestone powder slurries, solid masses content is 50%-60%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510969567.4A CN105418411A (en) | 2015-12-21 | 2015-12-21 | Preparation method for easily soluble calcium hydrogen citrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510969567.4A CN105418411A (en) | 2015-12-21 | 2015-12-21 | Preparation method for easily soluble calcium hydrogen citrate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105418411A true CN105418411A (en) | 2016-03-23 |
Family
ID=55497019
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510969567.4A Pending CN105418411A (en) | 2015-12-21 | 2015-12-21 | Preparation method for easily soluble calcium hydrogen citrate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105418411A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110002991A (en) * | 2019-04-09 | 2019-07-12 | 宁乡新阳化工有限公司 | A kind of production method for mending magnesium raw material magnesium acid citrate |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20010098992A (en) * | 2001-07-30 | 2001-11-09 | 박성식 | The preparation method of calcium hydrogen citrate and calcium citrate used as lime stone or shells |
| CN102241584A (en) * | 2011-05-06 | 2011-11-16 | 安徽丰原生物化学股份有限公司 | Production method of calcium hydrogen citrate |
| CN103044239A (en) * | 2012-12-17 | 2013-04-17 | 日照金禾博源生化有限公司 | Production method of sodium citrate |
| CN103058853A (en) * | 2012-12-17 | 2013-04-24 | 日照金禾博源生化有限公司 | Method for producing calcium hydrogen citrate |
-
2015
- 2015-12-21 CN CN201510969567.4A patent/CN105418411A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20010098992A (en) * | 2001-07-30 | 2001-11-09 | 박성식 | The preparation method of calcium hydrogen citrate and calcium citrate used as lime stone or shells |
| CN102241584A (en) * | 2011-05-06 | 2011-11-16 | 安徽丰原生物化学股份有限公司 | Production method of calcium hydrogen citrate |
| CN103044239A (en) * | 2012-12-17 | 2013-04-17 | 日照金禾博源生化有限公司 | Production method of sodium citrate |
| CN103058853A (en) * | 2012-12-17 | 2013-04-24 | 日照金禾博源生化有限公司 | Method for producing calcium hydrogen citrate |
Non-Patent Citations (1)
| Title |
|---|
| 陈连蔚等: "《柠檬酸氢钙水合物的制备与表征》", 《应用化工》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110002991A (en) * | 2019-04-09 | 2019-07-12 | 宁乡新阳化工有限公司 | A kind of production method for mending magnesium raw material magnesium acid citrate |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103058853B (en) | A kind of production method of calcium hydrogen citrate | |
| CN206428007U (en) | A kind of process units of granular-grade medicinal sodium bicarbonate | |
| CN101293849B (en) | Process for preparing glutamic acid crystallization | |
| CN108191688A (en) | A kind of method synthesized and crystallize D-VB5 calcium | |
| CN103044239B (en) | Production method of sodium citrate | |
| CN107312004A (en) | A kind of production method of folic acid | |
| CN102092759B (en) | Method for preparing strontium dichloride hexahydrate | |
| CN114132950A (en) | Method for preparing ammonium chloride by co-production of sodium bicarbonate | |
| CN103058235B (en) | Method of removing calcium with magnesium sulfate and high-purity magnesium sulfate | |
| CN106044802B (en) | A kind of complete water-soluble crystal process for producing potassium sulfate | |
| CN114259961A (en) | System and method for improving capacity of lithium battery anode material precursor and regulating and controlling particle size distribution of precursor | |
| CN105418411A (en) | Preparation method for easily soluble calcium hydrogen citrate | |
| CN104261435B (en) | A kind of double decomposition potassium nitrate crystal system and crystallization processes | |
| WO2022222324A1 (en) | Method for controlling coarse crystallization of hemihydrate gypsum | |
| WO2022222323A1 (en) | Process for producing phosphoric acid by using high-yield hydrated crystalline phase reconstruction wet method | |
| CN105753728B (en) | A kind of dilution crystallization method of pharmaceutical grade L valines | |
| CN104355983B (en) | A kind of method for crystallising of coarse granule shape nickel acetate | |
| CN107892313A (en) | Utilize saltcake refined brine and the process units and production method of by-product dihydrate gypsum | |
| CN105669428B (en) | A kind of production method of calcium hydrogen citrate | |
| CN101696022B (en) | Process for producing food grade saleratus by double decomposition | |
| CN103012217A (en) | Method for preparing high-purity aminoguanidine bicarbonate | |
| CN101774561A (en) | Process for preparing large grained food-grade calcium hydrogen phosphate | |
| CN111518119B (en) | Continuous amoxicillin crystallization process | |
| CN104876815A (en) | Sodium diformate preparation method | |
| CN100522927C (en) | Process for preparing EDTA disodium salt |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20160323 |