Zinc dichromate

  • Chromic acid, zinc salt (1:1)
  • Dichromic acid, zinc salt (1:1)
  • Zinc bichromate
  • Zinc chromium oxide
  • Zinc dichromate (Vi)
Formula
ZnCr2O7
Structure
Uses
As a pigment zinc dichromate trihydrate.

Registry Numbers and Inventories.
CAS
14018-95-2
EC (EINECS/ELINCS)
237-843-0
RTECS
HX7755000
RTECS class
Other
Beilstein/Gmelin
135515 (G)
RCRA
D007
Canada DSL/NDSL
NDSL
US TSCA
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
Cr2O7Zn
Formula mass
281.38

Hazards and Protection.
Storage
In general toxic materials or that can decompose into toxic components should be stored in cool ventilated place, out of sun, away from fire hazard. Substance must be periodically inspected and monitored. Incompatible materials should be isolated. Chromium cmpd protect against physical damage. Store in a dry location separate from combustible, organic or other readily oxidizable materials. Avoid storage on wood floors. Remove and dispose of any spilled dichromates; do not return to original containers. Dichromates Storage site should be close to lab so that only small quantities required for experimentation need to be carried. Carcinogens should be kept in only one section of storage area, explosion-proof refrigerator or freezer as required. The area should be appropriately labeled. An inventory should be kept showing the quantity of carcinogen and date it was acquired. Facilities for dispensing should be contiguous to storage area.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Rubber gloves, face shield or goggles. Handle in effective fume removal device from behind explosion-resistant barrier. Protective clothing should be of distinctive color, as a reminder not to be worn outside the laboratory.
Respirators
Any self-contained breathing apparatus with a full facepiece and operated in a pressure-demand or other positive pressure mode or any supplied-air repirator with a full facepiece and operated in a pressure-demand or other positive pressure mode in combination with an auxiliary self-contained breathing apparatus operated in pressure-demand or other positive pressure mode.
Small spills/leaks
Evacuate area and ventilate. Wear protective equipment. If required, use an inert absrobent. Sweep up and place in an appropriate container for disposal. Wash contaminated surfaces.
Stability
Trivalent chromium is the most stable oxidation state and hexavalent chromium is the second most stable state.
Incompatibilities
Avoid contact with combustible, organic, or other readily oxidizable materials. In contact with substances which are readily oxidized, can react rapidly enough to cause ignition, and with finely divided oxidizable substances combustion can be violent.

Fire.
Fire fighting
Fire fighting phases: Use flooding amount of water. Dichromates respiratory protection from chromic acid and chromates while fighting fires: Self-contained breathing apparatus with a full facepiece operated in pressure-demand or other positive pressure mode. Chromic acid and chromates

Health.
Exposure limit(s)
IDHL: NIOSH considers all chromic acid and chromates (CrO3) compounds as
Carcinogin
G-A1, I-1, N-1, CP65
Exposure effects
Hepatic encephalopathy, cerebral edema, and coma may occur. Both trivalent and hexavalent chromium have been found to cross the placental barrier in hamsters and mice. Both were shown to enter the fetus during mid to late gestation. Developmental effects caused by both differed between hamster and mice. Fetal uptake of hexavalent chromium was much greater than that of the trivalent form. Effects on placental tissue could have also affected the fetus.
   Ingestion
Gastroenteritis and hemorrhage frequently occur immediately following oral ingestion.
   Inhalation
Pulmonary edema, pneumoconiosis, metal fume fever, and bronchial asthma may occur.
   Skin
Deep perforating ulcers and hypersensitivity dermatitis may be noted. Systemic toxicity has resulted from minimal dermal exposure.

First aid
 
   Ingestion
Dilution: immediately dilute with 4 to 8 ounces (120 to 240 ml) of milk or water (not to exceed 4 ounces/120 ml in a child). Do not induce vomiting.
   Inhalation
Move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with beta2 agonist and corticosteroid aerosols.
   Skin
Wash the exposed area with water or 10 to 20 percent ascorbic acid solution for 15 minutes. Consult a physician if irritation or pain persists.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
USCG CHRIS Code
ZBC