Chromium chloride

Physical Properties

Physical properties

appearance and traits: dark red or dark purple slanting crystal, easy to solve.

Melting point (° C): 196

relative density (water = 1): 2.70

boiling point (° C): 250 (decomposition)

< P> Molecular formula: CRO 3

molecular weight: 99.99

Solubility: Soluble in water, sulfuric acid, nitric acid.

Chemical properties

is slightly decomposed at melt. Oxygen is released from 200 to 250 ° C to form an intermediate compound between chromium chromium and chromium dioxide. Evil oxide is formed into a peroxide. It is a strong oxidant. Contact friction with organic matter can cause combustion. In case of alcohol, benzene can happen or explode.

3c 5 oh + 2cro 3 + 3h 2 so 4

3ch 3 CHO + CR 2 (SO 4 ) 3 > + 6H 2 o

Synthesis method

1, sulfuric acid method: react with sodium erythric acid heating with sulfuric acid, retail after the reaction , Sodium hydrogen sulfate, re-cooling, discharge formulation, packaging, to produce chromic anhydride. The reaction is as follows:

2h 2 so 4 + na 2 cr 2 o 7 → 2 cro 3 +2 nahso 4 + h 2 o

2, Chromium ore is hot and limestone, and then uses concentrated sulfuric acid.

3, sulfuric acid method, nitric acid method, fluorosilic acid method, and electrolysis. The industrial main use of sulfuric acid. After mixing anhydrous red chromate and sulfuric acid in the reaction kettle, heated to 200 ° C for melt reaction, to obtain a melt product chromic anhydride and sodium hydrogen sulfate, and then stozy, cooled.

4, taking 100 g of dehydrated water after water and water reissolic acid sodium was dissolved in 250 ml of water and filtered, 400 ml of concentrated sulfuric acid was added slowly in a transparent filtrate. Because it is very dangerous to add excessive places, it must pay attention to the rising speed of the temperature when adding. After heating after the addition, the purple red CRO 3 is started. After 24 h, the precipitated crystallization was filtered, and several times were washed repeatedly until no adsorbed sulfuric acid was repeated with concentrated nitric acid, then dried.

5, it is also possible to replace the sodium red chromate. 10 g of potassium titanate was dissolved in 100 ml of water, and 50 ml of 95% sulfuric acid was slowly added, and it was quickly heated, gradually precipitated in purple CRO 3 . Placed 24h, most of the needle crystals were paired, filtered with a glass sand core funnel, washed with nitric acid to remove sulfuric acid, and was filled into a glass bottle.


1, mainly used in electroplating industries, making bicycles, sewing machines, watches, instruments, flashlights, daily hardware, etc., is also used to make high purity metals. chromium. It is a raw material for producing chromium oxide green and zinc chrome; it is also a raw material for producing a low temperature transform catalyst, a high temperature transform catalyst and a high pressure methanol synthesis catalyst. When woolen fabric is stained, it is used as a mediatact agent, and the printing and dyeing industry is used as an oxidant. In addition, it is also used for wood corrosion.

2, it is used as a catalyst for suppressing polyethylene in Philips;

3, an important chromium compound, chromic anhydride is the main raw material of the electroplating industry, used as The main raw material of electroplated chromium. Most of the chromic anhydride consumption is in the electroplating industry. Chromic anhydride is a good oxidant, which can be used for bleaching, refining, as well as a catalyst of a pigment, a vehicle, a tanning agent, and an organic synthetic reaction. In addition, it is also used in pharmaceutical, ceramic, colored glass and other industries.

4, the preparation of analyzing reagents, strong oxidants and chromate.

5 is used as a catalyst for synthetic polyethylene. Also used for chromium plating, medium and pure metal chromium.

6, the application of galvanized passivation in the passivation of galvanized layers, chromic anhydride is used, which is the main component of film formation. In aluminum and alloy chemical oxidation, chromic anhydride is an oxidant in solution, and is an indispensable component of forming a film layer.

7 for electroplating industries, pharmaceutical industries, printing industries, tanning and fabric media.

Usage Precautions

Hazard Overview

Health Hazard: Acute poisoning: After inhalation can cause acute respiratory irritation symptoms, nose bleeding, hoarseness, nasal mucosa Wrink, sometimes asthma and purple. Chemical pneumonia can occur. Oral can stimulate and corrode the digestive tract, causing nausea, vomiting, abdominal pain, blood, etc., severe breathing difficult, purple, shock, liver damage, acute renal failure, etc. Chronic impact: there are contact dermatitis, chromgemic ulcers, rhinitis, nasal septum perforation and respiratory inflammation.

Environmental hazard: It is harmful to the environment, which can cause pollution to the water body.

Danger of the explosion: This product is combustion, high toxic, is carcinogens, corrosive, irritating, and can cause human burns.

First aid measures

Skin contact: remove contaminated clothes, thoroughly rinse the skin with soap water and clear water.

Eye contact: lift eyelids, flush with flow clear water or physiological saline. Medical doctor.

Inhalation: Quickly leave the site to the fresh air. Keep the respiratory tract smooth. If breathing is difficult, give oxygen. If the breathing is stopped, artificial breathing immediately. Medical doctor.

Enter: Drinking the amount of warm water, drinking the soap water. Wash the stomach with water or 1% sodium thiosulfate. Drink milk or egg white. Medical doctor.

Firefighting action

Hazardous characteristics: strong oxidant. The contact with flammable (such as benzene) and combustible materials such as sugar, cellulose, etc., even cause combustion. After mixing with reducing substances such as magnesium powder, aluminum powder, sulfur, phosphorus, can cause combustion or explosion. Has strong corrosiveness.

Harmful combustion products: It may produce harmful gray toxic smoke.

Fire extinguishing method: use haze water, sand extinguishing.

Self-help mode: as soon as possible, you will go to the vents.

Leak emergency treatment

emergency treatment: isolation leak pollution zone, limited to the entrance. It is recommended to wear dust masks (full shroud) to wear dust-proof masks. Do not touch the leak directly. Do not contact the leakage with organic matter, reducing agents, and flammable materials.

small amount leak: Collected with a clean shovel in a dry, clean, covered container. Or rinse with a lot of water, washed with water and put it into the wastewater system.

A large number of leaks: collecting recycling or transporting waste disposal places.

Operation and storage

Operation notes: closed operation, strengthen ventilation. Operators must conduct special training and strictly abide by the operating procedures. It is recommended that the operator wears a self-suction filter dust mask, a chemically safe protective glasses, penetrating polyethylene antivotys, wearing rubber gloves. Smoking is strictly prohibited from fire, heat source, and workplace. Stay away from flammable, combustible materials. Avoid dust. Avoid contact with reducing agents, active metal powders. Lightly load and remove it when carrying it, prevent packaging and container damage. Fire protection equipment and leak emergency treatment equipment equipped with corresponding varieties and quantities. Empty containers may be harmful residues.

Storage Notes: Store in a cool, dry, well-ventilated warehouse. The library temperature does not exceed 35 ° C, and the relative humidity does not exceed 75%. The packaging must be sealed, don't be tidy. It should be stored separately with Easy (23) combustion, reducing agents, active metal powders, and consumption chemicals, cutting. The storage area should have a suitable material to accommodate leakage. The "five-parallel" management system "five-parallel" management system should be strictly enforced.

Storage method

Store in a cool, dry, well-ventilated warehouse. The library temperature does not exceed 30 ° C, relative humidity is not more than 80%. The packaging must be sealed, don't be tidy. It should be stored separately with Easy (23) combustion, reducing agents, active metal powders, and consumption chemicals, cutting. The storage area should have a suitable material to accommodate leakage.

Safety Information

Hazardous transportation code: UN 1463 5.1 / Pg 2

Dangerous goods logo: extreme toxic oxidant hazardous environment

safety Logo: 53-45-60-61-36 / 37 / 39-28-26-22

DANGER ID: R9R26R35R45R46R62R24 / 25R42 / 43R48 / 23R50 / 53

Chemical data

1, hydrophobic parameter calculation reference value (xlogp): None

2, hydrogen bond donor number: 0

3, the number of hydrogen bond receptors: 3

4, the number of rotary chemical bonds: 0

5, the number of tautomers: no

6, topological molecular polarity surface area: 51.2 < / p>

7, heavy moments: 4

8, surface charge: 0

9, complexity: 61.8

10, isotope atom Number: 0

11, determine the number of atomic integer: 0

12, uncertain atomic integer center quantity: 0

13, determining chemical keys Number of Structure: 0

14, Uncertainty Chemical Keys Structure Center Number: 0

15, Number of Co-Bond Units: 1

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