Maleic Acid
High purity organic acid for industrial applications, resin production, chemical synthesis, and water treatment
Overview
Maleic Acid (CAS No: 110-16-7) is a dicarboxylic acid that is the cis-isomer of fumaric acid. It is an important chemical raw material produced on an industrial scale. It occurs as colorless crystals and has high solubility in water.
Due to its high reactivity, maleic acid is used in various chemical reactions. It is widely used in the polymer industry, resin production, and agricultural chemicals. It also plays an important role in water treatment processes and metal coating.
Applications
Maleic Acid has a wide range of industrial applications:
Polymer Industry
Used in the production of polyester resins, alkyd resins, and other polymers. Particularly serves as a cross-linking agent in unsaturated polyester resins.
Water Treatment
Used in water treatment systems to prevent scale and calcium buildup. Especially effective in industrial cooling towers and steam boilers.
Agricultural Chemicals
Used as an intermediate in the production of herbicides and pesticides. An important component in the synthesis of plant growth regulators.
Food Additives
Used as a raw material in the production of fumaric acid. Fumaric acid is widely used as an acidity regulator in foods (E297).
Metal Coating
Used in the cleaning and coating processes of metal surfaces. Particularly effective in zinc and tin coating processes.
Other Applications
Used in dye production, pharmaceutical intermediates, textile dyes, and pulp processing industries.
Technical Specifications
| Property | Value | Unit | Test Method |
|---|---|---|---|
| Chemical Formula | C₄H₄O₄ | - | - |
| CAS Number | 110-16-7 | - | - |
| EC Number | 203-742-5 | - | - |
| Molecular Weight | 116.07 | g/mol | - |
| Appearance | White crystalline powder | - | Visual |
| Odor | Odorless | - | - |
| Density (25°C) | 1.59 | g/cm³ | ASTM D4052 |
| Melting Point | 130-135 | °C | ASTM D1015 |
| Boiling Point | 135 (decomposes) | °C | ASTM D1078 |
| Water Solubility (20°C) | 788 | g/L | ASTM E1148 |
| pH Value (0.1M sol.) | 1.5 | - | ASTM E70 |
| Purity | ≥99.0% | % | HPLC |
| Ash Content | ≤0.05 | % | ASTM D482 |
| Heavy Metal Content (Pb) | ≤10 | ppm | ICP-OES |
| Fumaric Acid Content | ≤0.5 | % | HPLC |
Safety Information
Hazard Symbols and Statements
Irritant Health Hazard Environmental Hazard
Personal Protective Equipment (PPE)
- Acid-resistant gloves (nitrile or neoprene)
- Dust mask or respiratory protection
- Chemical goggles or face shield
- Chemical-resistant apron
Storage Conditions
- Store in a cool, dry, and well-ventilated area
- Keep in original packaging, tightly closed
- Storage temperature: 15-25°C
- Keep away from bases, oxidizers, and metals
- Protect from moisture and light
Fire Fighting
- Suitable extinguishers: Water spray, dry chemical, CO₂
- Irritating gases (carbon monoxide, carbon dioxide) may be released during fire
- Firefighting personnel should protect themselves
Handling and Storage
Transportation
- Ensure containers are tightly closed
- Transport separately from oxidizers and bases
- Protect from moisture during transport
- Keep neutralizing materials available for spills
- Provide adequate ventilation in transport vehicles
Storage
- Store in polyethylene, glass, or stainless steel containers
- Display appropriate signs in storage areas
- Keep acid neutralizing materials in storage areas
- Provide secondary containment for large quantities
- Storage shelves should be made of corrosion-resistant material
Spill Measures
- Evacuate exposed personnel from the area
- Use appropriate personal protective equipment
- Clean up without raising dust
- Contain spill with sand, sodium bicarbonate or other neutralizing materials
- Wash the spilled area thoroughly with water
Regulatory Information
GHS Classification
- Skin Irritation Category 1B
- Serious Eye Damage Category 1
- Acute Toxicity (Oral) Category 4
Important Regulations
- REACH: Registered
- CLP: Compliant
- FDA: Limited use in food contact applications
- EPA: Registered
Compliance Certificates
- ISO 9001:2015
- ISO 14001:2015
- REACH Compliance Certificate
- Safety Data Sheet (MSDS) available
Environmental Information
Environmental Impact
Maleic acid shows moderate toxicity in aquatic environments. It can be harmful to aquatic life at high concentrations. It is biodegradable in soil but may have acidic effects in large quantities.
Biodegradation
- Air: Degrades through photochemical reactions
- Water: Degrades at moderate rate through microbial activity
- Soil: Degrades through microbial activity
Waste Management
- Classified as hazardous waste
- Should be disposed of by neutralizing in licensed waste disposal facilities
- Should not be discharged into sewers or surface waters
- Dispose of in accordance with local regulations
Frequently Asked Questions
What is the difference between maleic acid and fumaric acid?
Maleic acid and fumaric acid are geometric isomers (cis and trans forms respectively). Maleic acid has higher water solubility and lower melting point. Fumaric acid is more widely used in the food industry.
Is maleic acid used in foods?
Maleic acid is not used directly as a food additive, but it is used as a raw material in the production of fumaric acid. Fumaric acid is widely used as an acidity regulator in foods (E297).
What are the health effects of maleic acid?
Maleic acid is irritating to skin, eyes, and respiratory tract. If swallowed, it may cause gastrointestinal irritation. Avoid prolonged exposure and use appropriate personal protective equipment.
How does maleic acid work in water treatment?
Maleic acid prevents scale formation in water systems by forming complexes with calcium and magnesium ions. It works particularly effectively at high temperatures and increases system efficiency.
What should I do if maleic acid contacts skin?
Remove contaminated clothing immediately and wash skin with plenty of water and soap for at least 15 minutes. If irritation persists, seek medical attention. For eye contact, rinse eyes with plenty of water for at least 15 minutes and seek immediate medical attention.