In 1774, Acetaldehyde was first recognized by Carl Wilhelm Scheele. After that, its properties were explored by various chemists over the following decades. In 1835, Justus von Liebig used the term “aldehyde”. Later, ‘Aldehyde’ became known as Acetaldehyde.  

Acetaldehyde is an important chemical compound. CH₃CHO is the chemical bond of this chemical. It exists in liquid and gas forms at room temperature (20.8°C). If the room temperature is lower than 20.8°C, it becomes liquid. If the temperature increases above 20.8°C, it transforms into gas.   

It is widely used in producing perfumes, basic dyes, and polyester resins. It also works as a flavoring agent in alcohol.    

Acetaldehyde raises health concerns for both humans and animals. The EPA (U.S. Environmental Protection Agency) listed it as a probable human carcinogen (Group B2). In animals, it causes laryngeal tumor in Hamsters and nasal tumor in rats.     

 

Chemical Bond of Acetaldehyde

 

Chemical Bond:   

The chemical formula of Acetaldehyde is CH3CHO.  Acetaldehyde occurs in ripe fruit, bread, and coffee. This organic chemical compound contains two Carbon Atoms with five single bonds and one carbon-oxygen double bond.  

 

Properties:   

The molecular weight of Acetaldehyde is 44.06 g/mol. It is a colorless liquid and gas. It can be diluted in any proportion with water. Properties of Acetaldehyde are categorized into two types- physical properties and chemical properties, which are discussed below-    

 

Physical Properties    

  • Acetaldehyde is a colorless gas or liquid.    
  • This organic chemical has a pungent, fruity smell.    
  • CH3CHO or Acetaldehyde is soluble in water.    
  • The boiling point of the Acetaldehyde is 20.2°C (68.4°F).    
  • The melting point of the Acetaldehyde is −123.5°C (−190.3°F).    
  • The density of the Acetaldehyde is 0.784 g/cm³   
  • At 20°C temperature, the vapor pressure of the Acetaldehyde is 740mmHg. 

    

Chemical Properties    

  • Acetaldehyde can quickly oxidize to form acetic acid.    
  • Due to the existence of carbonyl groups, Acetaldehyde is highly reactive.    
  • This organic chemical can be reduced to Ethanol.    
  • CH3CHO or Acetaldehyde polymerizes to form paraldehyde and metaldehyde.    
  • Acetaldehyde reacts with alcohols, ammonia, and hydrogen cyanide.    
  • This organic chemical creates aldol condensation products with Ketones.   

 

Industrial Usage Acetaldehyde

Industrial Usage:    

 

Acetaldehyde (CH3CHO) is a flammable organic chemical. It is a volatile chemical. It is used across various industries.  Check out the key industries that produce this volatile chemical- 

 

Agricultural industries 

  •  Acetaldehyde is an intermediate in pesticide and herbicide production. 
  •  It helps synthesize growth regulators for plants and crops. 

 

Medical and pharmaceutical industries 

  • Acetaldehyde is used in the production of sedatives, tranquillizers, and vitamins. 
  •  This organic chemical is an intermediate in the synthesis of certain drugs. 

 

Personal care and cosmetic industries 

  • Acetaldehyde is a fragrance ingredient in personal care products and cosmetic industries. 
  • It is used in the production of synthetic musk and other aroma compounds. 

 

Foods and beverage industries 

  • Acetaldehyde is naturally found in fruits, coffee, and fermented products. 
  • This organic chemical is used as a flavoring agent in food and beverages. 
  • It is a byproduct of Ethanol. Ethanol plays a significant role in fermentation in alcoholic beverages like beer and wine. 

 

Chemical Industry

  • Acetaldehyde is an intermediate in producing ethyl acetate, acetic acid, and acetic anhydride.  
  • This organic chemical serves an essential role in synthesizing pyridine derivatives. Pyridine derivatives are used in pharmaceuticals and agrochemicals.  
  • Acetaldehyde also helps manufacture plastics and synthetic resins. 

 

 Textile & Leather Industry

  • Acetaldehyde helps in the tanning process of leather. 
  • It is used in textile finishing to improve fabric properties. 

 

Paper & Pulp Industry

 Here, Acetaldehyde is used as a bleaching agent to improve the whiteness of paper. 

 

Plastics & Rubber Industry

  • Acetaldehyde plays an essential role in polymerization processes for synthetic rubber and plastics. 
  •  It is used in the production of Butadiene. It is a crucial compound in rubber manufacturing. 

 

Fuel & Energy Industry

  •  Acetaldehyde works as an intermediate in the production of Bioethanol. It is a renewable fuel. 
  • Acetaldehyde is also used as an additive in gasoline. 

 

Hazards:   

 

1) Health Hazard   

 

Acute Effects   

  • In the human body, the primary effect of acute inhalation of Acetaldehyde is irritation of the skin, eye, and respiratory tract.   
  • Higher levels of exposure can cause pulmonary oedema, coughing, erythema, and necrosis.  
  • In animal bodies (hamsters, rabbits, and rats), acute inhalation of Acetaldehyde can cause depression in the respiratory tract and increase blood pressure.  

Chronic Effects   

  • The impact of Acetaldehyde on the human body is similar to that of alcohol. Acetaldehyde is the first product of Ethanol metabolism, and alcohol is Ethanol. Excessive alcohol consumption or environmental exposure to Acetaldehyde can cause skin flushing, hangovers, and chronic disease.   
  •  RfC (Reference Concentration) plays a significant role in chronic inhalation of Acetaldehyde. It helps as a guideline to analyze the potential risks of this organic chemical. For humans, RfC for Acetaldehyde is 0.009 mg/m3. It is estimated based on the degeneration of olfactory epithelium in rats. RfC plays a significant role in cases of chronic inhalation of Acetaldehyde.  
  • In animals, specifically hamsters, chronic inhalation of Acetaldehyde changes the nasal mucosa and trachea, slows growth, causes mild anemia, and increases kidney weight.     

 

Reproductive or Developmental Effects  

  • The reproductive effect of Acetaldehyde on the human body is unclear to date.    
  • In the animal body, especially in rats, Acetaldehyde injection causes reduced birth weight and skeletal malfunctions and increases the rate of post-natal mortality.  

 

Cancer risks  

  • The EPA (Environmental Protection Agency) has listed Acetaldehyde as a Group B2 carcinogen. It indicates that Acetaldehyde is a probable human carcinogen. The EPA uses a mathematical model to analyze the probability of developing cancer from breathing air containing Acetaldehyde. The analysis is based on mathematical models of human and animal studies.      

 

  • Acetaldehyde evaporates in the air quickly. Once this organic chemical becomes airborne, it breaks down into other substances. It happens naturally due to photochemical oxidation, reactions with hydroxyl radicals, etc. Because of quick degradation, Acetaldehyde won’t travel long distances.   

  

3) Environmental Hazard  

Acetaldehyde evaporates in the air quickly. Once the Acetaldehyde becomes airborne, it breaks down into other substances. It happens naturally due to photochemical oxidation, reactions with hydroxyl radicals, etc. Because of quick degradation, Acetaldehyde won’t travel long distances.  

Flammability   

  • Acetaldehyde is listed as highly flammable. It quickly ignites at relatively low temperatures. As per OSHA, the Permissible Exposure Limit (PEL) for Acetaldehyde is 200ppm (parts per million) for an 8-hour working day.   
  • Acetaldehyde vapors can form explosive mixtures in the air.   
  • This organic chemical can form an air mixture in closed tanks or containers.   

 

Safety Measures:   

 

When handling Acetaldehyde, employees need to follow some hygiene safety measures given by OSHA.  

 

  • Employees should check for Acetaldehyde presence before entering any confined place. This chemical can become airborne quickly. To ensure their safety, they should use some on-site screening devices. 

 https://www.osha.gov/chemicaldata/570 

 

  • It is essential to take off all contaminated clothes during the shift.   
  • It is necessary to wash hands before eating and after handling this organic chemical.  
  • Employees should use a mask to avoid direct inhalation of this organic chemical.   
  • Protecting eyes and face is necessary. Employees should use goggles and face shields to prevent splashes of this organic chemical.   
  • Wearing chemical-resistant gloves and PPE clothes is essential when handling this organic chemical. 

 

 

When spills or emergencies occur, employees need to follow some more safety measures given by OSHA.  

  • Employees need to evacuate the place quickly.  
  • When spills occur, employees should ensure proper ventilation in the affected area.  
  • If Acetaldehyde is present in any confined place, employees should remove it quickly. Otherwise, it will cause an explosion.  
  • Employees should absorb the liquid with cement powder and ash when leaks occur. Then, they should keep the mixture in a sealed container.  

 

Check out the First-aid measures:

 

For Eyes  

  • If the victims wear contact lenses, remove them quickly.  
  • Flush the victims’ eyes with clean or saline water for 20 to 30 minutes.  
  • Don’t apply any oil or ointment without instructions from the doctor.  
  • The victims should be sent to the hospital immediately.  

For Skin  

  • First, remove the victims’ clothing.   
  • Second, wash the victims’ affected skin with soap and water.   
  • Immediately transfer them to the hospital for a thorough medical checkup.   

 

For Inhalation  

  • Immediately leave the contaminated area and take a deep breath.  
  • In case of experiencing shortness of breath, wheezing, coughing, or a burning sensation in the throat, mouth, and chest, the victims should be taken to the hospital immediately.  

 

For Ingestion  

  • Acetaldehyde is a volatile chemical. Therefore, the victims should not be induced to vomit as it could cause severe medical complications.  
  • If the victims are unconscious or convulsing, they should be taken to the hospital immediately.   
  • Drinking 1 or 2 glasses of water is essential if the victims are conscious. After that, they should be taken to the hospital immediately.    

 

Conclusions  

The above discussion has pointed out that Acetaldehyde is essential in various industrial sectors. However, due to its toxic and potentially hazardous nature, industries must follow strict safety measures while balancing its environmental impact.