CHROME TANNING LIQUOR
Chrome tanning liquor is a key agent in the tanning process, where it stabilizes the collagen fibers of animal hides, making them durable and resistant to decomposition.
Chrome tanning liquor enhances the physical properties of leather, such as its tensile strength, flexibility, and resistance to heat, moisture, and microbial attack.
Chrome tanning liquor is an inorganic compound with the chemical formula Cr(OH)(SO4) and is typically sold in powder form.
CAS Number: 39380-78-4
EC Number: 235-595-8
Molecular Formula: CrH3O12S3
Molecular Mass: 343.208 g/mol
Synonyms: Koreon, Chromitan B, Baychrom A, Baychrom F, Chromitan MS, Chromitan NA, Cromitan B, Sulfuric acid, chromium salt, Chronisulfat, Chronisulfat, basic chromic sulfate, CHROMIUM(III) SULFATE BASIC, Chromium(Iii)SulphateBasic, CHROMIUM (III) SULPHATE BASIC Extra Pure, Chromic sulfate (basic), Chromosal B, Chromium sulfate, CHROMIC SULFATE, Chromium(III) sulfate, Chromium sulphate, 10101-53-8, Dichromium trisulfate, Chromic sulphate, Dichromium sulfate, Chromosulfuric acid, Dichromium sulphate, Dichromium trisulphate, Sulfuric acid, chromium salt, chromium(3+);trisulfate, UNII-Y0C99N5TMZ, 14489-25-9, Y0C99N5TMZ, Koreon, Chromitan B, Baychrom A, Baychrom F, Chromitan MS, Chromitan NA, Cromitan B, Chronisulfat, Chronisulfat, Chromium sulfate (VAN), Dichromium tris(sulphate), Chromium sulphate (2:3), CCRIS 6182, HSDB 2543, Chromium (III) sulfate, chromium(3+) trisulfate, EINECS 233-253-2, NSC 51151, UN2240, Chromisulfat, CI 77305, Chromium (III) sulfate (2:3), Chromosulfuric acid, 2Cr.3SO4, Chromic sulfate, CHEBI:53471, DTXSID20890642, 5170AF, AKOS015897499, FT-0658527, A800314, Sulfuric acid chromium(3+)salt(3:2),pentadecahydrate, SULFURIC ACID CHROMIUM(3+) SALT (3:2), PENTADECAHYDRATE, CHROMIUM SULFATE,BASIC, Chromium hydroxide sulfate, basic chrome sulphate, Chromosal B, basic chromic sulfate, Chromic sulfate (basic), chromium sulphate basic, chromic hydroxide sulfate, Chromium(Iii)SulphateBasic, CHROMIUM(III) SULFATE BASIC, chromium(3+) hydroxide sulfate, CHROMIUM (III) SULPHATE BASIC Extra Pure, Chromium (III) Sulphate Basic extrapure, 22.5% Cr
Chrome tanning liquor is used in dyeing of khaki cloth and in manufacture of chrome-based dyestuffs.
Chrome tanning liquor is often left in the technical product since it is inert with respect to the tanning process.
Chrome tanning liquor is important to fully reduce the hexavalent chromium to trivalent since the hexavalent is more likely to cause health problems for tanners and leather consumers.
Chrome tanning liquor is an inorganic compound with the chemical formula Cr(OH)(SO4).
Chrome tanning liquor is a green, odorless solid at room temperature.
Chrome tanning liquor is typically sold in powder form.
Chrome tanning liquor has high tanning power and hence largely used in the tanning of leather.
Chrome tanning liquor is easily soluble in cold water and very soluble in hot water.
Chromium, particularly in the hexavalent oxidation state, is toxic, hence Chrome tanning liquor, which is comparatively less toxic, is preferred in the leather industry.
Chrome tanning liquor are the mixture of various form of Chromium Sulphates including containing Chromium Hyrdoxide sulphate form chiefly.
Chrome tanning liquor is prepared by the reduction of Sodium Dichromate Solution in the presence of Sulphuric Acid or Sulfur dioxide.
The Cr2O3 content is 23.19% and a pH of 3.01, Chrome tanning liquor available in Dark green colour.
Ferrochromium and chromium based compounds are produced worldwide from chromite ore.
Chrome chemicals are from chromium based compounds.
Chrome tanning liquor is a chrome chemical mostly required as main tanning agent in chrome tanning process in leather industry and also to synthesize other chromic compounds.
Uses of Chrome tanning liquor:
Chrome tanning liquor finds its primary use in the leather industry as a crucial component in the tanning process. Here are the key uses of Chrome tanning liquor:
Leather Tanning:
Chrome tanning liquor is a key agent in the tanning process, where it stabilizes the collagen fibers of animal hides, making them durable and resistant to decomposition.
Stabilization of Collagen Fibers:
Chrome tanning liquor is used in the leather tanning process to cross-link collagen fibers in animal hides.
This cross-linking makes the leather more durable, flexible, and resistant to decomposition.
Improvement of Leather Qualities:
Chrome tanning liquor enhances the physical properties of leather, such as its tensile strength, flexibility, and resistance to heat, moisture, and microbial attack.
Softness and Drape:
Chrome tanning liquor helps in achieving desired softness and drape in leather, making it suitable for various applications in footwear, apparel, upholstery, and accessories.
Uses in Pottery:
Chrome tanning liquor can also be used in making ceramics, green ink, and organic substances.
Chrome tanning liquor can also be used for dyeing and printing.
Chrome tanning liquor is also used in green paints, varnishes, inks, and ceramic glazes.
Chrome tanning liquor can be used in tanning and retanning of any kind of leather including hides or skins.
Due to Chrome tanning liquor properties, Our product meets all requirements of a good leather tanning of any kinds.
Uniformity and evenness of color and tanning effect is one of the plus points of this product which is suitable for dyeing to any shade.
Leather made with this product is fine in grain and has a good compactness.
Chrome tanning liquor is compatible with other standard products used together with this product.
Applications of Chrome tanning liquor:
Chrome tanning liquor is mainly used in tanning of processing leather industry or synthesis of other chromium based re-tanning agents and production of chromic compound.
Chrome tanning liquor is also used in dyeing of khaki cloth and in manufacture of chrome-based dyestuffs.
Other Applications:
Chrome tanning liquor is used in some specialty pigments, and as a mordant in textile dyeing.
Manufacturing of Chrome tanning liquor:
During the preparation of Chrome tanning liquor, sodium dichromate containing chromium (VI) is reduced to chromium (III) by sulfur-di-oxide in a packed tower at a chemical process industry (B&M Chemicals, India) where the Chrome tanning liquor is produced at suboptimal efficiency due to inefficient (suboptimal) absorption of sulfur-di-oxide (as the gas enters the tower at a higher temperature) followed by reaction.
Improper reduction leads to the presence of unconverted chromium (VI) that imparts toxicity, not only through product basic-chromium- sulfate but also through leather and articles produced using this chemical.
Design and operating conditions of the packed bed absorber were found and effects of pH, temperature and concentration of SO2 on the performance of absorption were studied.
The reaction is favored at pH 4.
The overall efficiency of conversion in the tower is increased from 70% to 80% by operating the column at optimal operating conditions obtained using response surface method.
Dispersion is achieved by random packing that provides complex countercurrent flow path resulting in greater probability of entraining gas inside the tower.
Profiles of Chrome tanning liquor are obtained along the height of the tower by solving mathematical models of the reactive absorption process.
Chromium (VI) is 99% reduced to chromium (III) in the product.
Leached residues and liquid wastes are treated with either ferrous sulfate or sodium sulfide to convert chromium (VI) to chromium (III) to provide sustainable technology.
Treated solid waste is stored before safe disposal in hazardous landfill facility.
As chromium (VI) is highly toxic, several sustainable methods are suggested to eliminate Chrome tanning liquor from effluent to provide cleaner and sustainable production environment in the industry.
Chrome tanning liquor is produced from the simple reduction of Cr (VI) to Cr (III) by the addition of an excess of sulphur dioxide.
The reaction can be represented as:
Cr2O3 + 3 H2SO4 → Cr2(SO4)3 + 3 H2O
Another reaction, based on the same mechanism as above, for the production of Chrome tanning liquor industrially is:
Na2Cr2O7 + 3SO2 + H2O → 2Cr(SO4)(OH) + Na2SO4
The reaction is carried out in a steam-heated vessel.
The excess sulphur dioxide formed during the reaction is removed in another reaction tower.
Chrome tanning liquor obtained is in liquid state, Chrome tanning liquor is spray dried to form a powder, which is later packed in bags and sold.
In this study, Chrome tanning liquor was prepared, and the product was manufactured from the widely used triple chromium, in addition to sodium chr omate and calcium chromate in certain proportions at a temperature of 1200 °C, as well as using sulfuric acid and glucose as shown in the experiment.
Manufacturing until we get the final product.
Some of the devices used in the mass production process, such as the CSTR reactor and dryer, were designed, with a brief explanation of the rest of the devices used.
In addition, a study was conducted on the environmental impact of the product, in proportion to the industrial need and to achieve the slogan of clean and environmentally friendly work.
Although there is no environmental impact of the product that has been manufactured, care must be taken when dealing with these materials as well as safety and health precautions must be used professional establishments.
The sample was done and completed of the skin was taken and treated with the Chrome tanning liquor that was manufactured, and some chemical tests were conducted on the sample, and the conclusion is that the base percentage is 33.33%, the percentage of chromium oxide is 3.8%, and the total ash percentage is 2.25%, and these percentages show the quality of the product.
Reactions of Chrome tanning liquor
Chrome tanning liquor is produced from chromate salts by reduction with sulfur dioxide, although other methods exist.
The reduction could formally be written:
Na2Cr2O7 + 3 SO2 + H2O → Cr2(SO4)3 + 2 NaOH
Since 33% of the anion charges are due to hydroxy ions the basicity is 33% (but in tanning jargon it is known as 33% reduced).
Products with higher basicities, e.g. 42% or 50% may be obtained by the addition of sodium carbonate, these are often used in combination with sodium formate.
Production method of Chrome tanning liquor:
The production methods of Chrome tanning liquor mainly include organic reduction method and sulfur dioxide reduction method.
The organic matter reduction method uses sodium dichromate mother liquor with sodium bisulfate solution (40~42 ° Bé) or sulfuric acid in a lead-lined or glass-lined stirred reactor for stirring and acidification, and slowly adds sucrose reducing agent under stirring.
The hexavalent chromium is reduced, and the solution is kept boiling at the end of the reaction, which is conducive to the complete reaction.
The reaction product is a syrup-like viscous liquid.
Add water to adjust the concentration of the solution to 40~42 ° Bé.
First, Chrome tanning liquor is naturally cooled, and then frozen to below 10 ℃ in a cooling crystallizer to make part of the sodium sulfate form mirabilite crystals.
After centrifugal separation, a liquid Chrome tanning liquor product is prepared, and then concentrated and dried to obtain a solid Chrome tanning liquor finished product.
Preparation Method of Chrome tanning liquor:
The production methods of Chrome tanning liquor mainly include organic matter reduction method and sulfur dioxide reduction method.
Organic reduction method:
After sodium dichromate mother liquor is acidified with sodium bisulfate solution or sulfuric acid in a lead-lined or glass-lined reactor with stirring, sucrose reducing agent is slowly added under stirring to reduce hexavalent chromium, at the end of the reaction, the boiling of the solution is maintained, which is beneficial to the completion of the reaction.
The reaction product is a syrup-like viscous liquid.
Water is added to adjust the concentration of the solution to 40-42086, and the solution is first naturally cooled, and then frozen in a cooling crystallizer to below 10 ℃ to make part of the sodium sulfate to form mirabilite crystals, after centrifugal separation, liquid Chrome tanning liquor product was prepared, and then concentrated and dried to obtain solid Chrome tanning liquor product.
Handling and Storage of Chrome tanning liquor:
Handling:
Precautions:
Wear appropriate personal protective equipment (PPE) such as gloves, safety goggles, and protective clothing to avoid skin and eye contact.
Handle the liquor in a well-ventilated area to avoid inhalation of fumes.
Avoid:
Prevent spills and splashes.
Do not eat, drink, or smoke in areas where chrome tanning liquor is used.
Hygiene:
Wash hands and any exposed skin thoroughly after handling the chemical.
Storage:
Conditions:
Store chrome tanning liquor in a cool, dry place away from heat sources and direct sunlight.
Ensure that storage areas are well-ventilated.
Containers:
Use containers made of materials compatible with chrome tanning liquor.
Label containers clearly with the chemical name and hazard information.
Segregation:
Keep away from incompatible materials such as strong acids, strong bases, and oxidizing agents.
Stability and Reactivity of Chrome tanning liquor:
Stability:
Chemical Stability:
Chrome tanning liquor is generally stable under recommended storage conditions.
Shelf Life:
Follow manufacturer’s guidelines for shelf life and replacement intervals.
Reactivity:
Incompatibilities:
Avoid contact with strong acids, strong bases, and oxidizing agents as these can cause hazardous reactions.
Hazardous Decomposition Products:
Decomposition may produce toxic chromium compounds and other hazardous fumes.
Hazardous Reactions:
Polymerization:
Chrome tanning liquor does not polymerize.
Fire Risk:
The liquid is generally not flammable but can be hazardous if spilled or heated.
First Aid Measures of Chrome tanning liquor:
General Advice:
Seek Medical Attention:
In case of significant exposure or symptoms, seek medical attention promptly.
Inhalation:
Get the affected person to fresh air immediately.
If breathing is difficult, provide oxygen.
If not breathing, perform artificial respiration. Seek medical help.
Skin Contact:
Remove contaminated clothing and wash the affected skin area with plenty of water and soap.
Seek medical attention if irritation persists.
Eye Contact:
Rinse eyes immediately with plenty of water for at least 15 minutes, lifting the upper and lower eyelids occasionally.
Seek medical attention immediately.
Ingestion:
Do Not Induce Vomiting:
Rinse mouth with water and seek medical attention immediately.
If conscious, give water to dilute the chemical.
Firefighting Measures of Chrome tanning liquor:
Flammability:
Non-Flammable:
Chrome tanning liquor is not classified as flammable.
However, the chemical components may pose risks in certain conditions.
Extinguishing Media:
Use Suitable Agents:
Use water spray, foam, dry chemical, or carbon dioxide (CO₂) for fire extinguishing.
Ensure fire extinguishing agents are suitable for the type of fire.
Special Hazards:
Hazardous Combustion Products:
May produce toxic fumes and gases, including chromium compounds, when exposed to high temperatures.
Protective Equipment for Firefighters:
Wear PPE:
Firefighters should wear full protective gear, including self-contained breathing apparatus (SCBA) to avoid inhalation of hazardous fumes.
Firefighting Instructions:
Cool Containers:
Keep containers cool with water spray if exposed to fire.
Avoid water runoff into drains and water sources.
Accidental Release Measures of Chrome tanning liquor:
Personal Precautions:
Protective Gear:
Wear appropriate PPE including gloves, goggles, and protective clothing.
Ventilate the area and avoid inhaling vapors.
Environmental Precautions:
Containment:
Prevent the chemical from entering drains, watercourses, or soil.
Use barriers to contain spills.
Containment and Cleanup:
Small Spills:
Absorb with inert materials (e.g., sand, earth) and place in appropriate disposal containers.
Large Spills:
Dike the area to contain the spill.
Use suitable materials to absorb the liquid. Dispose of waste according to regulations.
Decontamination:
Clean Up:
Clean the area thoroughly after the spill has been contained and removed.
Follow proper disposal procedures for contaminated materials.
Exposure Controls/Personal Protective Equipment of Chrome tanning liquor:
Exposure Limits:
Regulations:
Follow occupational exposure limits set by relevant regulatory agencies (e.g., OSHA, ACGIH).
Engineering Controls:
Ventilation:
Use local exhaust ventilation or fume hoods to maintain airborne concentrations below exposure limits.
Ensure good general ventilation in work areas.
Personal Protective Equipment:
Respiratory Protection:
Use an appropriate respirator with chemical cartridges if ventilation is inadequate or if exposure limits are exceeded.
Skin Protection:
Wear chemical-resistant gloves (e.g., nitrile, neoprene) and protective clothing to avoid skin contact.
Eye Protection:
Use safety goggles or face shields to protect eyes from splashes and vapors.
Body Protection:
Wear appropriate protective clothing such as lab coats or aprons to avoid contact with the chemical.
Hygiene Measures:
After Handling:
Wash hands, face, and any exposed skin thoroughly after handling chrome tanning liquor.
Avoid contact with food, drink, and smoking in areas where the chemical is used.
Identifiers of Chrome tanning liquor:
CAS No: 39380-78-4
Chemical Formula: CrH3O12S3
Molecular Mass: 343.208 g/mol
Melting Point: 90C
Density: 1.7g/cm3
PH 1.5-2.5
Water Solubility: Soluble in water
Color: Green Crystalline
Physical State: Powder
Formula: Cr4(SO4)5(OH)2
Molecular Weight: 343.208 g/mol
Form: Fine free flowing, Dark green color powder
CAS Number: 39380-78-4
Density: 1.7 g/cm³
Chemical Name: Chrome tanning liquor
Chemical Formula: Cr(OH)SO4 or Cr(OH)SO4·xH2O (where x can vary, indicating hydration state)
CAS Number: 39380-78-4 (for the hydrated form)
EINECS Number: 254-400-5
Properties of Chrome tanning liquor:
grade: puriss.
SMILES string: [Cr+3].[Cr+3].[Cr+3].O[Cr+]O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O
InChI: 1S/4Cr.5H2O4S.2H2O/c;;;;5*1-5(2,3)4;;/h;;;;5*(H2,1,2,3,4);2*1H2/q4*+3;;;;;;;/p-12
InChI key: CHFNDYXSNLPPCO-UHFFFAOYSA-B
Properties of Chrome tanning liquor:
Melting point: 90°C
density: 1.7
form: Solid
color: Green Crystalline
Odor: Odorless
PH Range: 1.5 - 2.5
Water Solubility: Soluble in water
Specifications of Chrome tanning liquor:
Appearance: Greenish to bluish-green powder or solid
Solubility: Soluble in water
pH of 10% Solution: Typically around 2.5 - 3.5
Chromium Content: Typically 23-26% by weight
Impurities:
Iron (Fe): Typically less than 0.1% by weight
Sulfate (SO4): Typically less than 2% by weight
Insoluble Matter: Typically less than 0.2% by weight
Related Products of Chrome tanning liquor:
Copper Sulphate
Copper Sulphate Anhydrous
Magnesium Sulphate Heptahydrate
Manganese Sulphate
MeSH of Chrome tanning liquor:
Chrome tanning liquor
chromium (+2) sulfate (1:1)
chromium (+3) sulfate (3:2)
chromium (+3) sulfate (3:2), hexahydrate
chromium (+3) sulfate (3:2), pentadecahydrate
chromium sulfate
chromium sulfate basic
chromosulfuric acid
