CN110967239B - Method for dissolving and oxidizing metallic chromium - Google Patents
Method for dissolving and oxidizing metallic chromium Download PDFInfo
- Publication number
- CN110967239B CN110967239B CN202010002634.6A CN202010002634A CN110967239B CN 110967239 B CN110967239 B CN 110967239B CN 202010002634 A CN202010002634 A CN 202010002634A CN 110967239 B CN110967239 B CN 110967239B
- Authority
- CN
- China
- Prior art keywords
- chromium
- aqueous solution
- deionized water
- heating
- hydrogen chloride
- 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.)
- Active
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)
Abstract
The application discloses a method for dissolving and oxidizing metallic chromium, belongs to the technical field of a sample dissolving treatment method before chromium isotope measurement, and solves the problem that in the prior art, oxidizing acid is adopted to easily generate an oxide film or a gas product on the surface of metallic chromium to cause chromium loss. According to the method for dissolving and oxidizing the chromium metal, the chromium metal and concentrated hydrochloric acid are mixed and reacted to obtain a chromium trichloride aqueous solution; mixing a chromium trichloride aqueous solution with hydrogen peroxide, and oxidizing trivalent chromium ions in the chromium trichloride to hexavalent chromium ions by the hydrogen peroxide in a weakly alkaline environment. The process of the present application is used to oxidize trivalent chromium ions to hexavalent chromium ions.
Description
Technical Field
The application relates to a method for treating a dissolved sample before chromium isotope measurement, in particular to a method for dissolving and oxidizing metallic chromium.
Background
Before the chromium isotope measurement, the sample to be measured and the chromium isotope standard are pretreated to convert the chromium element in the sample to be measured into hexavalent chromium. Because hexavalent chromium is readily soluble in water and stable in air.
In the prior art, metal chromium is generally oxidized into hexavalent chromium by using an oxidizing acid (nitric acid and perchloric acid), but an oxide film or a gas product is easily generated on the surface of the metal chromium by using the oxidizing acid, so that the loss of the chromium is caused. Chromium reacts with concentrated nitric acid to produce chromium oxide (Cr)2O3) A dense oxide film is formed, hindering further reaction of nitric acid with chromium: 6HNO3+2Cr＝Cr2O3+3H2O+6NO2×) @. Chromium may react with perchloric acid to produce chromium dichloride (CrO)2Cl2) Gas and gradual evaporation leads to losses.
Content of application
In view of the above analysis, the present application aims to provide a method for dissolving and oxidizing metallic chromium, which solves the problem in the prior art that an oxidizing acid is used to easily generate an oxide film on the surface of metallic chromium or a gas product is used to cause chromium loss.
The purpose of the application is mainly realized by the following technical scheme:
the application provides a method for dissolving and oxidizing metallic chromium, which comprises the steps of mixing and reacting the metallic chromium with concentrated hydrochloric acid to obtain a chromium trichloride aqueous solution; mixing a chromium trichloride aqueous solution with hydrogen peroxide, and oxidizing trivalent chromium ions in the chromium trichloride to hexavalent chromium ions by the hydrogen peroxide in a weakly alkaline environment.
In one possible design, the pH of the weakly alkaline environment is 8-10.
In one possible design, the following steps are included:
step 1: weighing 10-20 mg of chromium powder;
step 2: adding 0.5-1 mL of concentrated hydrochloric acid into chromium powder, standing until the chromium powder is completely dissolved, and mixing the chromium powder and the concentrated hydrochloric acid for reaction;
and step 3: removing hydrogen chloride in the chromium trichloride aqueous solution with the residual hydrogen chloride to obtain a chromium trichloride aqueous solution;
and 4, step 4: uniformly mixing 1-1.5 mL of hydrogen peroxide with the mass fraction of 30% with a chromium trichloride aqueous solution, then dropwise adding 0.02-0.05 mL of concentrated ammonia water, uniformly mixing, standing until the solution becomes a bright orange yellow solution, and oxidizing trivalent chromium ions in chromium trichloride to hexavalent chromium ions by using the hydrogen peroxide in a weakly alkaline environment.
In one possible design, in step 2, the chromium powder is completely dissolved by means of ultrasonic vibration and/or heating.
In one possible design, step 3 includes the steps of:
and (3) heating the chromium trichloride aqueous solution with the residual hydrogen chloride in a water-proof way, so that the hydrogen chloride is completely evaporated to obtain the chromium trichloride aqueous solution.
In one possible design, the temperature of the heating against water is below 80 ℃.
In one possible design, step 3 includes the steps of:
heating the chromium trichloride aqueous solution with the residual hydrogen chloride from the container and quantitatively transferring the chromium trichloride aqueous solution into a plastic tube, washing the container for three times by using deionized water, and quantitatively transferring the deionized water washed by the container into the plastic tube; placing a glass beaker on the electric heating plate, placing the plastic tube in the glass beaker, and heating the electric heating plate to volatilize the hydrogen chloride until the hydrogen chloride is evaporated to dryness; adding 1.8-2.2 mL of deionized water, and heating an electric heating plate until the deionized water is evaporated to dryness; and adding 0.9-1.1 mL of deionized water, and dissolving all chromium trichloride to obtain a chromium trichloride aqueous solution.
In one possible design, step 4 is followed by the following steps:
and 5: removing hydrogen peroxide and ammonia water.
In one possible design, step 5 includes the steps of: heating the bright orange solution in a water-proof way to ensure that the hydrogen peroxide and the ammonia water are completely volatilized.
In one possible design, step 5 includes the steps of: quantitatively transferring the bright orange solution into a plastic tube, placing a glass beaker on an electric hot plate, and placing the plastic tube into the glass beaker; heating the electric heating plate until the bright yellow solution is evaporated to dryness; adding 1.8-2.2 mL of deionized water, and heating until the solution is evaporated to dryness; and adding 1.8-2.2 mL of deionized water to dissolve the hexavalent chromium.
Compared with the prior art, the application can at least realize the following beneficial effects:
a) compared with the prior art, the metal chromium dissolving and oxidizing method provided by the application utilizes hydrochloric acid to dissolve metal chromium, and oxidizes trivalent chromium ions to hexavalent chromium ions under the alkalescent condition by using hydrogen peroxide, so that the problem of generating an oxide film or a gas product when oxidizing the metal chromium by using oxidizing acid (nitric acid and perchloric acid) is solved, the yield of the hexavalent chromium ions is improved, and tests show that the yield of the hexavalent chromium ions can approach or reach 100% by using the metal chromium dissolving and oxidizing method, and a mixture of the trivalent chromium ions and the hexavalent chromium ions cannot be obtained, so that subsequent other separation steps are not needed.
Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. The objectives and other advantages of the application may be realized and attained by the structure particularly pointed out in the written description.
Detailed Description
Preferred embodiments of the present application are described in detail below.
The application provides a metal chromium dissolving and oxidizing method, which comprises the steps of mixing metal chromium (such as chromium powder) and concentrated hydrochloric acid for reaction to obtain a chromium trichloride aqueous solution; mixing a chromium trichloride aqueous solution with hydrogen peroxide, and oxidizing trivalent chromium ions in the chromium trichloride to hexavalent chromium ions by the hydrogen peroxide in a weak alkaline environment (for example, the pH value is 8-10), wherein the reaction formula is as follows:
2Cr+6HCl＝2CrCl3+3H2 (1)
2CrCl3+10NH3·H2O+3H2O2＝2(NH4)2CrO4+6NH4Cl+8H2O (2)
compared with the prior art, the metal chromium dissolving and oxidizing method provided by the application utilizes hydrochloric acid to dissolve metal chromium, and utilizes hydrogen peroxide to oxidize trivalent chromium ions to hexavalent chromium ions under the alkalescent condition, so that the problem of generating oxide films or gas products when oxidizing metal chromium by using oxidizing acid (nitric acid and perchloric acid) is solved, the yield of the hexavalent chromium ions is improved, and tests show that by adopting the metal chromium dissolving and oxidizing method, the yield of the hexavalent chromium ions can approach or reach 100%, and a mixture of the trivalent chromium ions and the hexavalent chromium ions cannot be obtained, so that other subsequent separation steps are not needed.
In a broad sense, concentrated hydrochloric acid means hydrochloric acid with a mass fraction of more than 20%; typically, the concentration of concentrated hydrochloric acid is commercially available at 36 wt.% to 38 wt.%.
Specifically, the method comprises the following steps:
step 1: weighing 10-20 mg of chromium powder, and adding into a centrifugal tube;
step 2: adding 0.5-1 mL of concentrated hydrochloric acid into a centrifuge tube containing chromium powder through a liquid transfer device, placing until the chromium powder is completely dissolved, mixing the chromium powder and the concentrated hydrochloric acid to react, wherein the addition amount of the hydrochloric acid is far greater than that of the chromium powder, so that the chromium powder can fully react to obtain a chromium trichloride aqueous solution with residual hydrogen chloride;
and step 3: removing hydrogen chloride in the chromium trichloride aqueous solution with the residual hydrogen chloride to obtain the chromium trichloride aqueous solution, wherein the purpose of the step is to prepare for subsequently adjusting the pH value to be alkaline;
and 4, step 4: uniformly mixing 1-1.5 mL of hydrogen peroxide with the mass fraction of 30% with a chromium trichloride aqueous solution by using a pipettor, then dropwise adding 0.02-0.05 mL of concentrated ammonia water (14.5 mol/L), uniformly mixing, placing until the solution becomes a bright orange yellow solution (the color of hexavalent chromate is bright orange yellow), and oxidizing trivalent chromium ions in chromium trichloride to hexavalent chromium ions by using the hydrogen peroxide in a weakly alkaline environment.
It should be noted that the order of adding hydrogen peroxide and strong ammonia water can not be changed, if strong ammonia water is added first, then a violent reaction will be generated immediately during the process of adding hydrogen peroxide, which is easy to generate accidents. Compared with the trivalent chromium content, 1-1.5 mL of hydrogen peroxide with the mass fraction of 30% is far excessive, and the trivalent chromium can be fully oxidized. The concentrated ammonia water mainly has the function of making the solution alkalescent and does not introduce other metal ions.
In order to promote the dissolution of the chromium powder in the concentrated hydrochloric acid, in the step 2, ultrasonic vibration and/or heating (e.g., a water bath at 55-62 ℃) may be adopted.
In order to remove the hydrogen chloride as much as possible, the volatility of the hydrogen chloride can be utilized, and the step 3 can comprise the following steps: and (3) heating the chromium trichloride aqueous solution with the residual hydrogen chloride in a water-proof way, so that the hydrogen chloride is completely evaporated to obtain the chromium trichloride aqueous solution. Wherein, the temperature of water-proof heating should be controlled to be lower than 80 ℃ as much as possible, and the solution is prevented from bumping.
Specifically, the step 3 may include the steps of: heating the chromium trichloride aqueous solution with the residual hydrogen chloride from a container (15mL centrifuge tube) and quantitatively transferring the chromium trichloride aqueous solution into a 50mL plastic tube, washing the container for three times by using deionized water, and quantitatively transferring the deionized water washed by the container into the 50mL plastic tube; placing a glass beaker on an electric heating plate, placing a 50mL plastic tube in the glass beaker, and heating the electric heating plate to volatilize the hydrogen chloride till the hydrogen chloride is almost evaporated to dryness; adding 1.8-2.2 mL of deionized water, and heating an electric heating plate until almost all the deionized water is evaporated to dryness; and adding 0.9-1.1 mL of deionized water, and dissolving all chromium trichloride to obtain a chromium trichloride aqueous solution.
Considering the effect of residual hydrogen peroxide, step 4 of the above method may further include the following steps:
and 5: removing hydrogen peroxide and ammonia water.
In order to remove hydrogen peroxide and ammonia as much as possible by utilizing the volatility of hydrogen peroxide and ammonia, the step 5 may include the steps of: heating the bright orange solution in a water-proof way to ensure that the hydrogen peroxide and the ammonia water are completely volatilized.
Specifically, the step 5 may include the steps of: quantitatively transferring the bright orange yellow solution into a 50mL plastic tube, placing a glass beaker on an electric hot plate, and placing the 50mL plastic tube into the glass beaker; heating the electric heating plate until the bright yellow solution is almost evaporated to dryness; adding 1.8-2.2 mL of deionized water, and heating until the solution is almost evaporated to dryness; and adding 1.8-2.2 mL of deionized water to dissolve the hexavalent chromium.
Illustratively, with a cation exchange resin, the pretreatment of the chromium solution comprises the steps of:
step A: sucking 1ml of AG50W-X8 cation exchange resin by a suction pipe, and injecting the cation exchange resin into an ion exchange column; washing the ion exchange column with 15ml (5 ml × 3) of 50% nitric acid, and collecting the washing solution (5 ml per tube); washing with 20 ml (5 ml × 4) of deionized water, and collecting;
and B: adding 5ml of sample into an ion exchange column, and collecting the sample passing through the ion exchange column;
and C: eluting the ion exchange column with 20 ml (5 ml × 4) of deionized water, and collecting hexavalent chromium ions;
step D: the ion exchange column was rinsed with 15ml (5 ml. times.3) of 50% nitric acid, and trivalent chromium ions were collected to complete the pretreatment of the chromium powder.
The method adopts anion exchange resin, and the pretreatment of the chromium powder comprises the following steps:
step A: sucking 1ml AG1-X4 anion exchange resin by a suction pipe, and injecting the cation exchange resin into an ion exchange column; washing the ion exchange column with 15ml (5 ml × 3) of 50% nitric acid, and collecting the washing solution (5 ml per tube); washing with 20 ml (5 ml × 4) of deionized water, and collecting;
and B: adding 5ml of sample into an ion exchange column, and collecting the sample passing through the ion exchange column;
and C: rinsing the ion exchange column with 20 ml (5 ml × 4) of deionized water, and collecting trivalent chromium ions;
step D: the ion exchange column was rinsed with 15ml (5 ml. times.3) of 50% nitric acid, and hexavalent chromium ions were collected to complete the pretreatment of the chromium powder.
The pretreatment of the chromium solution also includes purification of the ion exchange resin prior to removal of organic and metallic impurities from the ion exchange resin (cation exchange resin or anion exchange resin).
Specifically, the purification of the ion exchange resin comprises the steps of: soaking ion exchange resin in alcohol with three times of volume, shaking and standing, removing upper-layer alcohol, and repeating for three times to obtain lower-layer isolate; washing the lower-layer isolate by deionized water, and removing residual alcohol to obtain a washed lower-layer isolate; soaking the washed lower-layer separated substance in 50% nitric acid solution (2-3 times volume), shaking and standing, removing the upper-layer solution, and repeating for three times; washing with deionized water for three times to complete the purification of the ion exchange resin, and storing the purified ion exchange resin in 1% nitric acid solution.
Example one
The method for dissolving and oxidizing metallic chromium comprises the following steps:
step 1: weighing 20mg of chromium powder, and adding into a centrifugal tube;
and 2, step: adding 0.5 concentrated hydrochloric acid into a centrifuge tube containing chromium powder through a liquid transfer device, standing until the chromium powder is completely dissolved, and mixing the chromium powder and the concentrated hydrochloric acid to react to obtain a chromium trichloride aqueous solution with residual hydrogen chloride;
and step 3: removing hydrogen chloride in the chromium trichloride aqueous solution with the residual hydrogen chloride to obtain a chromium trichloride aqueous solution;
and 4, step 4: 1mL of hydrogen peroxide with the mass fraction of 30% is uniformly mixed with a chromium trichloride aqueous solution by using a pipettor, then 0.02 concentrated ammonia water (14.5 mol/L) is added dropwise, the mixture is uniformly mixed and placed until the solution becomes a bright orange yellow solution, trivalent chromium ions in chromium trichloride are oxidized to hexavalent chromium ions by using the hydrogen peroxide in a weak alkaline environment, and tests show that the yield of the hexavalent chromium ions in the embodiment is 99.99%.
Example two
The method for dissolving and oxidizing metallic chromium comprises the following steps:
step 1: weighing 16mg of chromium powder, and adding the chromium powder into a centrifugal tube;
step 2: adding 0.7mL of concentrated hydrochloric acid into a centrifuge tube containing chromium powder through a pipettor, standing until the chromium powder is completely dissolved, and mixing the chromium powder and the concentrated hydrochloric acid to react to obtain a chromium trichloride aqueous solution with residual hydrogen chloride;
and step 3: removing hydrogen chloride in the chromium trichloride aqueous solution with the residual hydrogen chloride to obtain a chromium trichloride aqueous solution;
and 4, step 4: 1.5mL of hydrogen peroxide with the mass fraction of 30% is uniformly mixed with a chromium trichloride aqueous solution by using a pipettor, then 0.03 dropwise adding concentrated ammonia water (14.5 mol/L), uniformly mixing, placing the mixture until the solution becomes a bright orange yellow solution, oxidizing trivalent chromium ions in chromium trichloride to hexavalent chromium ions by using hydrogen peroxide in a weakly alkaline environment, and testing shows that the yield of the hexavalent chromium ions in the embodiment is 99.98%.
EXAMPLE III
The method for dissolving and oxidizing metallic chromium comprises the following steps:
step 1: weighing 10mg of chromium powder, and adding into a centrifugal tube;
step 2: adding 1mL of concentrated hydrochloric acid into a centrifuge tube containing chromium powder through a pipettor, standing until the chromium powder is completely dissolved, and mixing the chromium powder and the concentrated hydrochloric acid to react to obtain a chromium trichloride aqueous solution with residual hydrogen chloride;
and step 3: removing hydrogen chloride in the chromium trichloride aqueous solution with the residual hydrogen chloride to obtain a chromium trichloride aqueous solution;
and 4, step 4: 1.1mL of hydrogen peroxide with the mass fraction of 30% is uniformly mixed with a chromium trichloride aqueous solution by using a pipettor, then 0.05mL of concentrated ammonia water (14.5 mol/L) is added dropwise, the mixture is uniformly mixed and placed until the solution becomes a bright orange yellow solution, trivalent chromium ions in the chromium trichloride are oxidized to hexavalent chromium ions by the hydrogen peroxide in a weak alkaline environment, and tests show that the yield of the hexavalent chromium ions in the embodiment is 100%.
The above description is only for the preferred embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application.
Claims (8)
1. The method for dissolving and oxidizing metallic chromium is characterized by comprising the following steps:
step 1: weighing 10-20 mg of chromium powder;
step 2: adding 0.5-1 mL of concentrated hydrochloric acid into chromium powder, standing until the chromium powder is completely dissolved, and mixing the chromium powder and the concentrated hydrochloric acid for reaction;
and step 3: removing hydrogen chloride in the chromium trichloride aqueous solution with the residual hydrogen chloride to obtain a chromium trichloride aqueous solution;
and 4, step 4: uniformly mixing 1-1.5 mL of hydrogen peroxide with the mass fraction of 30% with a chromium trichloride aqueous solution, then dropwise adding 0.02-0.05 mL of concentrated ammonia water, uniformly mixing, placing until the solution becomes a bright orange yellow solution, and oxidizing trivalent chromium ions in chromium trichloride to hexavalent chromium ions by using the hydrogen peroxide in a weakly alkaline environment;
the concentration of the concentrated hydrochloric acid is 36-38 wt.%;
the pH value of the weak alkaline environment is 8-10;
the method for pretreating chromium powder by adopting anion exchange resin comprises the following steps:
step A: sucking 1ml of anion exchange resin by a suction pipe, and injecting cation exchange resin into an ion exchange column; washing the ion exchange column by using 15ml of 50% nitric acid, and collecting a washing liquid; washing with 20 ml of deionized water, and collecting;
and B: adding 5ml of sample into an ion exchange column, and collecting the sample passing through the ion exchange column;
and C: eluting the ion exchange column by using 20 ml of deionized water, and collecting trivalent chromium ions;
step D: and (3) eluting the ion exchange column by using 15ml of 50% nitric acid, and collecting hexavalent chromium ions to finish the pretreatment of the chromium powder.
2. The method for dissolving and oxidizing metallic chromium according to claim 1, wherein in the step 2, the chromium powder is completely dissolved by ultrasonic vibration and/or heating.
3. The method of claim 1, wherein step 3 comprises the steps of:
and heating the chromium trichloride aqueous solution in which the hydrogen chloride is remained by water separation to ensure that the hydrogen chloride is completely evaporated to obtain the chromium trichloride aqueous solution.
4. The method of claim 3, wherein the heating over water is performed at a temperature of less than 80 ℃.
5. The method of claim 3, wherein the step 3 comprises the steps of:
heating the chromium trichloride aqueous solution with the residual hydrogen chloride from the container and quantitatively transferring the chromium trichloride aqueous solution into a plastic tube, washing the container for three times by using deionized water, and quantitatively transferring the deionized water washed by the container into the plastic tube; placing a glass beaker on the electric heating plate, placing the plastic tube in the glass beaker, and heating the electric heating plate to volatilize the hydrogen chloride until the hydrogen chloride is evaporated to dryness; adding 1.8-2.2 mL of deionized water, and heating an electric heating plate until the deionized water is evaporated to dryness; and adding 0.9-1.1 mL of deionized water, and dissolving all chromium trichloride to obtain a chromium trichloride aqueous solution.
6. The method of claim 1, wherein the step 4 is followed by the steps of:
and 5: removing hydrogen peroxide and ammonia water.
7. The method of claim 6, wherein the step 5 comprises the steps of:
heating the bright orange solution in a water-proof way to ensure that the hydrogen peroxide and the ammonia water are completely volatilized.
8. The method of claim 7, wherein the step 5 comprises the steps of:
quantitatively transferring the bright orange solution into a plastic tube, placing a glass beaker on an electric hot plate, and placing the plastic tube into the glass beaker; heating the electric heating plate until the bright yellow solution is evaporated to dryness; adding 1.8-2.2 mL of deionized water, and heating until the solution is evaporated to dryness; and adding 1.8-2.2 mL of deionized water to dissolve the hexavalent chromium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010002634.6A CN110967239B (en) | 2020-01-02 | 2020-01-02 | Method for dissolving and oxidizing metallic chromium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010002634.6A CN110967239B (en) | 2020-01-02 | 2020-01-02 | Method for dissolving and oxidizing metallic chromium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110967239A CN110967239A (en) | 2020-04-07 |
| CN110967239B true CN110967239B (en) | 2022-05-10 |
Family
ID=70037959
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010002634.6A Active CN110967239B (en) | 2020-01-02 | 2020-01-02 | Method for dissolving and oxidizing metallic chromium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110967239B (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4704188A (en) * | 1983-12-23 | 1987-11-03 | Honeywell Inc. | Wet chemical etching of crxsiynz |
| CN103575585B (en) * | 2013-10-11 | 2016-08-31 | 西北稀有金属材料研究院 | A kind of low beryllium content copper alloy metallographic etching agent and the display methods of low beryllium content copper alloy metallographic structure |
| CN104897661A (en) * | 2015-05-08 | 2015-09-09 | 河南奥鑫合金有限公司 | Combined determination method for main components in high-carbon ferrochrome slag |
| JP6952695B2 (en) * | 2015-12-09 | 2021-10-20 | サンシャイン・レイク・ファーマ・カンパニー・リミテッドＳｕｎｓｈｉｎｅ Ｌａｋｅ Ｐｈａｒｍａ Ｃｏ．，Ｌｔｄ． | Influenza virus replication inhibitors, their application and use |
| CN110514499A (en) * | 2019-09-19 | 2019-11-29 | 深圳市华保科技有限公司 | A kind of pre-treatment optimization method promoting the solid waste Cr VI detection rate of recovery |
-
2020
- 2020-01-02 CN CN202010002634.6A patent/CN110967239B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110967239A (en) | 2020-04-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107132219A (en) | A kind of method for continuously measuring of Zinc in Zinc Concentrates and iron content | |
| CN110967239B (en) | Method for dissolving and oxidizing metallic chromium | |
| CN110526455B (en) | Method for recycling uranium from uranium-containing wastewater | |
| Johnson et al. | Isotopic oxygen-18 exchange between aqueous vanadyl ions and water | |
| Heitner-Wirguin et al. | Kinetic behaviour of chelating resins with phosphonic functional groups | |
| CN111504751A (en) | Sample pretreatment method for determining total iron content | |
| Candlin et al. | 828. Sulphur–nitrogen compounds. Part I. The hydrolysis of sulphamate ion in perchloric acid | |
| CN113740320B (en) | Method for analyzing copper impurity content in waste lead-acid storage battery recovery process | |
| CN116593635A (en) | Method for detecting aluminum content in lithium iron phosphate positive electrode waste powder | |
| CN110702844B (en) | Method for analyzing and determining aluminum content in organic nucleating agent by Fenton-like reagent | |
| Ishibashi et al. | Ultraviolet Spectrophotometric Determination of Iron (III) as Chloro-complex | |
| CN108508137A (en) | The assay method of lead content in a kind of ore of precise and high efficiency | |
| CN116754349B (en) | ICP-OES-based digestion method for lithium sulfide impurity elements and content determination method thereof | |
| TWI814139B (en) | Method for removing boron from boron-containing solution | |
| CN113916972B (en) | Method for measuring content of trace tungsten in nickel | |
| CN116660184A (en) | Method for detecting ammonia nitrogen content in sulfuric acid process titanium dioxide waste acid | |
| Chernorukov et al. | Heterogeneous Equilibria in the System MHSiUO 6· n H 2 O-Aqueous Solution (M= Li, Na, K) | |
| CN119661039A (en) | A pretreatment method, impurity removal method and application of nickel-containing sludge | |
| Rahmoeller et al. | Isotopic oxygen exchange between aqueous vanadyl ions and solvent water | |
| Neal et al. | Adapting LEU-Modified Cintichem Process for Processing Up to 750 Grams of Uranium Targets | |
| CN119845694A (en) | Method for separating, purifying and determining Cu isotopes in basalt or olivine samples | |
| Rao et al. | Complexation of the uranyl ion (UO22+) with phenylene-1, 2-dioxydiacetic acid | |
| Evans et al. | The cobalticyanide ion as a precipitant for metal ions. Determination of:(a) cadmium in Pb-Sb-Cd and Pb-Sn-Cd alloys;(b) silver in lead; manganese in citrate solutions | |
| CN114959267A (en) | Method for removing carbonate radicals in tungsten-molybdenum waste sodium carbonate leaching solution | |
| Powell et al. | A Primary Standard for Alkalimetry and Chelometry |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |