# Benzenesulfonic Acid Monohydrate (CAS 26158-00-9): A Comprehensive Guide to This Essential Industrial Chemical

Benzenesulfonic Acid Monohydrate (CAS 26158-00-9) is a vital organic sulfonic acid compound with the molecular formula C6H5SO3H·H2O and a molecular weight of 194.19 g/mol. This comprehensive guide explores its chemical properties, industrial applications, safety considerations, and why it’s an essential chemical for various manufacturing processes.

## What is Benzenesulfonic Acid Monohydrate?

Benzenesulfonic Acid Monohydrate is the hydrated form of benzenesulfonic acid, characterized by the addition of one water molecule to the core compound. It appears as a white to off-white crystalline solid or flakes and is highly soluble in water and alcohols.

This compound is also known by several synonyms:
– Phenylsulfonic acid monohydrate
– Benzenesulfonic acid 1-hydrate
– Benzenesulfonic acid monohydrate (1:1)

As an aromatic sulfonic acid, it contains a sulfonic acid group (-SO3H) attached to a benzene ring, making it a strong organic acid with excellent solvation properties.

## What Are the Benefits?

### Excellent Solubility and Acidic Properties

Benzenesulfonic Acid Monohydrate exhibits exceptional solubility in water and various organic solvents, making it highly versatile for different formulations. Its strong acidic nature (pKa ~1) makes it effective in applications requiring powerful acid catalysis.

### Versatile Intermediate

This compound serves as a crucial intermediate in the synthesis of numerous derivatives, including:
– Sodium benzenesulfonate
– Calcium benzenesulfonate
– Magnesium benzenesulfonate
– Various alkylbenzene sulfonates

### Cost-Effective Industrial Solution

Compared to other strong acids, benzenesulfonic acid offers a cost-effective solution for many industrial processes while providing consistent performance and reliability.

## What Are the Uses?

### Detergent and Cleaning Industry

The primary application of benzenesulfonic acid monohydrate is in the production of surfactants and detergents:
– **Linear Alkylbenzene Sulfonic Acid (LABSA)**: The compound is a key precursor in manufacturing LABSA, which is the most widely used anionic surfactant in household and industrial detergents
– **Laundry powders and liquids**: Provides excellent cleaning properties
– **Dishwashing liquids**: Effective grease removal
– **Household cleaners**: Used in various cleaning formulations
– **Industrial and Institutional (I&I) cleaners**: Heavy-duty cleaning applications

### Pharmaceutical Industry

In pharmaceutical manufacturing, benzenesulfonic acid monohydrate serves multiple purposes:
– **Drug intermediate**: Used in the synthesis of various pharmaceutical compounds
– **pH regulator**: Helps control acidity in drug formulations
– **Catalyst**: Facilitates certain chemical reactions in drug synthesis

Research has shown its potential in synthesizing HER2/EGFR dual inhibitors for cancer treatment, demonstrating its importance in developing anti-tumor agents.

### Dye and Pigment Industry

The compound plays a vital role in dye manufacturing:
– **Dye intermediates**: Essential component in producing various synthetic dyes
– **Colorant production**: Used in textile and paper dye formulations
– **Pigment dispersants**: Helps achieve uniform color distribution

### Agrochemical Applications

In agriculture, benzenesulfonic acid derivatives are used in:
– **Pesticide formulations**: Serves as a foundation for certain pesticide active ingredients
– **Herbicide production**: Components in weed control products
– **Fertilizer additives**: pH adjustment in agricultural chemicals

### Other Industrial Applications

Additional uses include:
– **Electroplating**: Electrolyte formulations
– **Textile processing**: Dyeing and finishing operations
– **Plastic additives**: Processing aids and stabilizers
– **Oil recovery**: Enhanced oil recovery operations

## Safety and Side Effects

### Hazard Classification

Benzenesulfonic Acid Monohydrate is classified as a hazardous substance:
– **Corrosive**: Causes severe skin burns and eye damage
– **Harmful if swallowed**: Acute toxicity concerns
– **Irritant**: May cause respiratory, skin, and eye irritation

### Safety Precautions

When handling this chemical, follow these essential safety guidelines:

**Personal Protective Equipment (PPE)**:
– Wear chemical-resistant gloves
– Use safety goggles or face shield
– Wear protective clothing and apron
– Use respiratory protection in poorly ventilated areas

**Storage Requirements**:
– Store in a cool, dry, well-ventilated area
– Keep away from incompatible materials (bases, oxidizers)
– Store in original container, tightly closed
– Avoid moisture exposure

**First Aid Measures**:
– **Skin contact**: Immediately remove contaminated clothing, rinse skin with water for at least 15 minutes
– **Eye contact**: Rinse cautiously with water for several minutes, remove contact lenses if present
– **Ingestion**: Do not induce vomiting, rinse mouth with water, seek medical attention
– **Inhalation**: Move to fresh air, seek medical attention if symptoms persist

### Environmental Considerations

Dispose of benzenesulfonic acid monohydrate according to local regulations. Do not release into drains, soil, or waterways. Neutralize before disposal and handle as hazardous waste.

## Chemical Specifications

| Property | Value |
|———-|——-|
| CAS Number | 26158-00-9 |
| Molecular Formula | C6H5SO3H · H2O |
| Molecular Weight | 194.19 g/mol |
| Appearance | White to off-white crystalline solid |
| Solubility | Highly soluble in water, alcohols |
| pH | ~1 (1% solution) |
| Melting Point | ~45-50°C |
| Boiling Point | Decomposes before boiling |
| Density | ~1.32 g/cm³ |

## Frequently Asked Questions

### What is the difference between benzenesulfonic acid and its monohydrate form?

The monohydrate form contains one water molecule attached to each molecule of benzenesulfonic acid. Both forms have similar chemical properties and uses, but the monohydrate form may be preferred in certain applications where controlled hydration is important.

### Is benzensulfonic acid monohydrate safe for household use?

While the compound itself is used in household products, it must be handled by trained professionals in industrial settings. The commercial products containing its derivatives are formulated to be safe for consumer use.

### How is benzenesulfonic acid monohydrate produced?

It is typically produced through the sulfonation of benzene with sulfuric acid, followed by dehydration and crystallization to obtain the monohydrate form. The process requires careful control of temperature and reaction conditions.

### What is the shelf life of this compound?

When stored properly in sealed containers under recommended conditions, benzenesulfonic acid monohydrate can maintain its stability for several years. However, it is hygroscopic and may absorb moisture from the air over time.

## Why Choose Our Benzenesulfonic Acid Monohydrate?

When sourcing Benzenesulfonic Acid Monohydrate for your industrial or research needs, consider these advantages:

– **High Purity**: Our product meets rigorous quality standards with purity levels of 98% or higher
– **Consistent Quality**: Each batch is tested to ensure consistent chemical specifications
– **Reliable Supply**: We offer stable supply chains for both small and large quantity orders
– **Technical Support**: Our team provides technical documentation and safety data sheets
– **Competitive Pricing**: Quality products at market-competitive prices
– **Global Shipping**: Efficient logistics to deliver products worldwide

## Related Products

If you’re interested in benzenesulfonic acid monohydrate, you may also find these related compounds valuable:

– [Linear Alkylbenzene Sulfonic Acid (LABSA)](https://longchangextracts.com) – Primary surfactant for detergents
– [Sodium Benzenesulfonate](https://longchangextracts.com) – Derivative used in various applications
– [Phenol](https://longchangextracts.com) – Related aromatic compound

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*This article is for informational purposes only and does not constitute medical or professional advice. Always consult with qualified professionals before handling industrial chemicals.*