chrome is in its chromium 3 form is used in leather industry for tanning.It exits in
transition states (oxitaion) which the following are most relvant to leathermaking
'trivalent chrome
these compound occur naturally in the environment .They are found in rocks,sol,plants and volcanic emissions.Chromium salt are present in foodstuffs and are a necessary nutrient for the human body.it is required for the normal metabolism of fats and sugers.
Nutritional supplements are currently on sale containing chromium picolinate.
Chromium (III) sulfate is safe to use and is non hazardous. It is used in the leather industry for tanning.
Hexavalent chromium (Cr VI)
This is the hazardous form of this element. It can be formed when trivalent chromium is oxidized. This usually occurs in the presence of oxygen combined with other factors, such as extremes in pH. The salts have a characteristic yellow color and are classified as carcinogens as they can easily penetrate the skin and adhere to tissue cells. When chrome tanned leather dye crust or crust is directly burn in presence of oxygen like this picture shown trivalent chromium sulphite change into Hexavalent chrome. Chrome III is used in the tanning process for chrome tanned leather and if the tanning processes are carried out correctly then the resulting leather will be completely safe to use.
In leather production, however there are three ways in which chrome III could oxidize into chrome VI.
During the tanning process
If the temperature or pH is too high then chrome III has the propensity to oxidize to chrome VI.
Chemical used
If chrome powder is sourced from a non-reputable supply then there is a possibility that it may contain chrome VI
Finished leather
After the leather has been made, there is a small chance of chrome III oxidizing into chrome VI at high temperatures. This is why chrome tanned leather should never be incinerated except under very strictly controlled condition.
transition states (oxitaion) which the following are most relvant to leathermaking
'trivalent chrome
these compound occur naturally in the environment .They are found in rocks,sol,plants and volcanic emissions.Chromium salt are present in foodstuffs and are a necessary nutrient for the human body.it is required for the normal metabolism of fats and sugers.
Nutritional supplements are currently on sale containing chromium picolinate.
Chromium (III) sulfate is safe to use and is non hazardous. It is used in the leather industry for tanning.
Hexavalent chromium (Cr VI)
This is the hazardous form of this element. It can be formed when trivalent chromium is oxidized. This usually occurs in the presence of oxygen combined with other factors, such as extremes in pH. The salts have a characteristic yellow color and are classified as carcinogens as they can easily penetrate the skin and adhere to tissue cells. When chrome tanned leather dye crust or crust is directly burn in presence of oxygen like this picture shown trivalent chromium sulphite change into Hexavalent chrome. Chrome III is used in the tanning process for chrome tanned leather and if the tanning processes are carried out correctly then the resulting leather will be completely safe to use.
In leather production, however there are three ways in which chrome III could oxidize into chrome VI.
During the tanning process
If the temperature or pH is too high then chrome III has the propensity to oxidize to chrome VI.
Chemical used
If chrome powder is sourced from a non-reputable supply then there is a possibility that it may contain chrome VI
Finished leather
After the leather has been made, there is a small chance of chrome III oxidizing into chrome VI at high temperatures. This is why chrome tanned leather should never be incinerated except under very strictly controlled condition.
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