Which is the best process for production of acetic acid?

Acetic acid is a vital commodity chemical, with a global demand exceeding 15 million tons annually. It serves multiple industries, from chemicals to food production. Currently, acetic acid is produced through two main routes: the chemical process, which dominates industrial practice, and the fermentative process.

Recent Advancements in Acetic Acid Production and Applications

Over the past two decades, significant strides have been made in the production and application of acetic acid. Innovations in catalysis and process intensification have placed a strong emphasis on sustainability. Today, acetic acid is indispensable across several sectors—including chemicals, pharmaceuticals, textiles, polymers, paints, and food and beverage manufacturing.

In the food industry, acetic acid is widely recognized as vinegar and is valued for its distinctive flavor and preservation qualities. It acts as an acidulant, enhances flavor profiles, decontaminates meat, and even functions as a mild descaling agent in food processing.

More recently, its use has expanded into antimicrobial edible coatings—a promising development in response to the growing demand for food safety and innovation. As global food culture diversifies, acetic acid presents itself as a versatile and efficient solution.

SL Tec offers professional and trustworthy services tailored to your chemical processing needs.

1. Introduction

Acetic acid, a clear liquid with a pungent smell and sharp taste, melts at 16.73C and boils at 117.9C. Known since ancient times—famously used by Hippocrates to clean wounds—acetic acid has evolved from a food preservative to a cornerstone of modern industry.

Today, it is a key building block in diverse sectors including food, pharmaceuticals, textiles, polymers, cosmetics, and more. With rising demand, acetic acid production is projected to hit 18 million tons, growing at an average of 5% annually.

2. Current Production Methods and Applications

Acetic acid is primarily produced through chemical routes, particularly via:

• Cativa process (carbonylation of methanol)

• Oxidation of aldehydes

• Oxidation of ethylene

Leading producers like BP Chemicals and BASF focus on the carbonylation route. Major uses include manufacturing vinyl acetate monomer (VAM), acetic anhydride, and C1–C4 acetates. VAM is critical in polymer production—employed in emulsifiers, surface coatings, acrylic fibers, and polymer wires. The textile industry also utilizes acetic acid in creating synthetic fibers via condensation reactions.

Acetic anhydride, another derivative, is used in producing cellulose acetate for textiles and photographic films. Additionally, esters like ethyl, n-butyl, isobutyl, and propyl acetate serve as solvents for inks, paints, and coatings. Glacial acetic acid, a high-purity form, is widely used as a recrystallization solvent in organic synthesis.

Meanwhile, fermentative production of acetic acid—primarily in the form of vinegar—is prevalent in the food industry, where it's valued for its natural preservation and flavor-enhancing properties. Recent innovations have seen it used in antimicrobial coatings for food packaging.

3. The Push for Sustainable Technologies

Growing environmental concerns and rising acetic acid demand call for novel, sustainable production methods. While numerous technologies exist, most struggle with high production costs and energy consumption—particularly in the separation stages, such as:

• Distillation

• Evaporation

• Absorption

• Crystallization

• Alkali neutralization

Although effective, these methods are time- and energy-intensive. On the other hand, fermentation cannot meet industrial-scale needs. Hence, innovative approaches like carbon-based feedstock and membrane separation technologies are gaining traction.

3.1 Utilizing CO and CO₂ as Feedstock

Carbon monoxide and carbon dioxide represent sustainable feedstock alternatives. BP has pioneered a process using syngas from natural gas—eliminating the need for CO purification and methanol purchasing. This innovation aligns with the SaaBre process, integrating three steps for acetic acid synthesis.

Another promising route involves converting CO₂ and H₂ into methanol, followed by carbonylation to produce acetic acid. These approaches turn waste gases into valuable resources.

3.2 Membrane-Based Separation Technologies

Membrane technology allows for precise separation of liquids, vapors, and gases, with controlled mass transfer and energy efficiency. Based on pore size, membranes are categorized as:

• Microfiltration

• Ultrafiltration

• Nanofiltration

These systems operate between 1 to 20 bar, depending on the membrane used. Reverse osmosis, utilizing non-porous membranes, functions above 20 bar. Membrane-based separation is ideal for downstream processing in both chemical and fermentative acetic acid production. Integrating fermentation with acetic acid-permeable membranes can prevent product inhibition and improve yield.

4. Applications in the Food Industry

Since ancient times, acetic acid has played a vital role in food preservation and medicine. Modern applications have expanded significantly, including:

• Food additive and preservative

• Antimicrobial agent

• Acidulant and flavor enhancer

• Edible packaging material

• Ripening agent

4.1 Acetification Process

Acetification refers to the bacterial oxidation of ethanol into acetic acid and water—an oxidative fermentation process. The efficiency of this reaction depends on the microorganism type and oxygen availability.

Curious to learn more about the Acetic Acid Production Process? Contact us today for expert consultation!