Strontium chromate Property

Melting point:

decomposes [KIR78]

Density 

3.895

solubility 

soluble in dilute acid solutions

form 

Powder

Specific Gravity

3.895

color 

yellow monoclinic crystals, crystalline

Water Solubility 

Soluble in boiling water, dilute HCl, dilute CH{3}CO{2}H

Merck 

14,8841

Solubility Product Constant (Ksp)

pKsp: 4.65

Exposure limits

ACGIH: TWA 0.0002 mg/m3; STEL 0.0005 mg/m3 (Skin)
OSHA: Ceiling 0.1 mg/m3
NIOSH: IDLH 15 mg/m3; TWA 0.0002 mg/m3

Stability:

Stability

CAS DataBase Reference

7789-06-2(CAS DataBase Reference)

EPA Substance Registry System

Strontium chromate (7789-06-2)

Safety

Hazard Codes 

T,N

Risk Statements 

45-22-50/53

Safety Statements 

53-45-60-61

RIDADR 

UN3087

TSCA 

Yes

HazardClass 

5.1

PackingGroup 

III

Hazardous Substances Data

7789-06-2(Hazardous Substances Data)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Hazard statements

H272May intensify fire; oxidizer

H303May be harmfulif swallowed

H350May cause cancer

H400Very toxic to aquatic life

H410Very toxic to aquatic life with long lasting effects

Precautionary statements

P201Obtain special instructions before use.

P220Keep/Store away from clothing/…/combustible materials.

P221Take any precaution to avoid mixing with combustibles/…

P405Store locked up.

Strontium chromate Chemical Properties,Usage,Production

Chemical Properties

Strontium chromate a light yellow crystalline solid or powder.

Strontium chromate is prepared by precipitating a suitably soluble chromate with an appropriate strontium salt. Finding a primary use in corrosion-inhibiting coatings, this pigment has poor tint strength, low opacity, and unsatisfactory alkali and acid resistance, which limits its more widespread use in the coatings industry. Little of this pigment is now manu- factured in the United States.

Uses

Strontium chromate is mainly used to prevent corrosion on aluminum, and primers containing this pigment are standard for the aviation industry. Strontium chromate is so effective at low loadings that it is often used to provide inhibition for coil coatings despite the fact that it is the most expensive chromate inhibitor. The pigment is sometimes combined with zinc chromate in water-based formulations. In these cases, to avoid stability problems, loadings are kept at low levels, about 2% total chromate.
Corrosion inhibitor in pigments; in electrochemical processes to control sulfate concentration of solutions.

Uses

Strontium Chromate is highly corrosive and a strong oxidizing agent. It’s used in chrome plating, corrosion inhibition, and as a colorant in polyvinyl chloride.

General Description

STRONTIUM CHROMATE is a light yellow powder or granular solid. STRONTIUM CHROMATE is insoluble in water. The primary hazard is the threat to the environment. Immediate steps should be taken to limit its spread to the environment. STRONTIUM CHROMATE is used as a pigment, a protective coating against corrosion, and in pyrotechnics.

Air & Water Reactions

STRONTIUM CHROMATE is insoluble in water. Reactivity in Water: Produces hazardous solution.

Reactivity Profile

Oxidizing agents, such as STRONTIUM CHROMATE, can react with reducing agents to generate heat and products that may be gaseous (causing pressurization of closed containers). The products may themselves be capable of further reactions (such as combustion in the air). The chemical reduction of materials in this group can be rapid or even explosive, but often requires initiation (heat, spark, catalyst, addition of a solvent). Explosive mixtures of inorganic oxidizing agents with reducing agents often persist unchanged for long periods if initiation is prevented. Such systems are typically mixtures of solids, but may involve any combination of physical states. Some inorganic oxidizing agents are salts of metals that are soluble in water; dissolution dilutes but does not nullify the oxidizing power of such materials. Organic compounds, in general, have some reducing power and can in principle react with compounds in this class. Actual reactivity varies greatly with the identity of the organic compound. Inorganic oxidizing agents can react violently with active metals, cyanides, esters, and thiocyanates. Avoid contact with water, acids, and bases.

Hazard

Toxic by ingestion. Confirmed carcinogen.

Health Hazard

INHALATION: Irritating to mucous membranes. SKIN: Repeated skin contact can cause eczematous dermatitis, with edema and ulceration. INGESTION: Dizziness, intense thirst, abdominal pain, vomiting, shock and oliguria or anuria.

Fire Hazard

Behavior in Fire: Heat stable

Safety Profile

Confirmed human carcinogen with experimental carcinogenic and tumorigenic data. Moderately toxic by ingestion. Mutation data reported. See also CHROMIUM COMPOUNDS and STRONTIUM COMPOUNDS.

Potential Exposure

Strontium chromate is used as a metal protective coating to prevent corrosion, in wash primers; and aluminum flake coatings; colorant in polyvinyl chloride resins and pyrotechnics.

Shipping

UN3086 Toxic solids, oxidizing, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, 5.1-Oxidizer. Technical Name Required.

Properties and Applications

TEST ITEMS	SPECIFICATION
APPEARANCE	LEMON YELLOW POWDER
SHADE	GREENISH
CONTENT of Sr (SrO)	46.5%
CONTENT of Cr (CrO3)	44.0%
HEAT RESISTANCE	600 °C min
LIGHT FASTNESS	7~8
ACID RESISTANCE	4
ALKALI RESISTANCE	4
FASTNESS TO BLEEDING	5
OIL ABSORPTION	20-28%
DENSITY	3.90 g/cm 3
RESIDUE ON 80 MESH	5.0% max
WATER SOLUBLE	1.0% max
VOLATITE 105 °C	1.0% max
TINTING STRENGTH	100-105 %

Purification Methods

Crystallise strontium chromate from water (40mL/g) by cooling.

Incompatibilities

Violent reaction with strong oxidizers, hydrazine. Incompatible with combustible, organic, or other readily oxidizable materials, such as paper, wood, sulfur, aluminum powder. Attacks plastics and coatings