Surfactants in Industrial Applications: Answers to 7 Key Questions That Bother You

Photo: RephiLe water / Unsplash

Surfactants are an indispensable part of many industrial processes – from cleaning and degreasing to stabilizing emulsions and dispersions. Nevertheless, their selection and use often raise questions that can affect the quality of the final product, production efficiency, or even worker safety. Typical issues such as excessive foaming, loss of effectiveness at extreme temperatures, or incompatibility with other mixture components can complicate even seemingly simple applications. In this article, we focus on specific queries raised by our clients – from manufacturers of cleaning agents to technologists in the automotive and construction industries – and provide proven solutions based on chemical principles and practical experience.

1. What Are Surfactants and How Do They Actually Work?

Surfactants, or surface-active agents, are chemical compounds capable of reducing the surface tension between two immiscible phases – typically between water and oil, water and a solid, or air and a liquid. This property is due to their amphiphilic structure: a surfactant molecule consists of a hydrophilic (water-attracting) and a hydrophobic (water-repelling) part. The hydrophilic part orients itself towards water, while the hydrophobic part binds to non-polar substances such as fats, oils, or dirt. This leads to emulsification, dispersion, or wetting, which forms the basis of their action in cleaning agents, cosmetics, coatings, and industrial processes.

In practice, surfactants are divided into four main groups based on the charge of the hydrophilic part: anionic (e.g., alkyl sulfates), cationic (e.g., quaternary ammonium salts), non-ionic (e.g., fatty alcohol ethoxylates), and amphoteric (e.g., betaines). Each group has specific properties and areas of application. Anionic surfactants, for example, are effective in removing dirt, while non-ionic surfactants are often used for their compatibility with other ingredients and low irritancy. The selection of the right type of surfactant depends on the specific application, desired efficacy, and compatibility with other formulation components.

2. How to Choose the Right Surfactant for a Specific Industrial Application?

Selecting a surfactant is not universal and requires consideration of several key factors. The first step is defining the desired function: should the surfactant be used for cleaning, emulsification, wetting, foaming, or, for example, as an antistatic agent? For instance, anionic surfactants are often chosen for industrial cleaning agents due to their high degreasing capacity, while non-ionic surfactants are preferred in coatings for stabilizing pigment dispersions and low foaming properties.

It is also necessary to consider the application conditions, such as the pH of the environment, temperature, presence of salts, or other chemicals. Some surfactants lose effectiveness in acidic or alkaline environments, while others may react with metal ions and form undesirable precipitates. Compatibility with materials that the surfactant will come into contact with is also important—for example, in the food industry, surfactants approved for contact with food according to REACH regulations and other standards are required. Last but not least, the economic aspect plays a role: highly specialized surfactants may be more expensive, but their effectiveness can reduce the overall formulation costs.

Photo: RephiLe water / Unsplash

3. What are the most common problems when working with surfactants, and how can they be prevented?

When working with surfactants, several typical problems may be encountered that can affect the quality of the final product or process. One of the most common is excessive foaming, which can complicate mixing, filling, or application. This issue is often addressed by combining low- and high-foaming surfactants or by adding defoamers. Another frequent phenomenon is phase separation, where the oil and water phases in emulsions separate. Stability can be improved by optimizing the surfactant ratio, adding co-emulsifiers, or adjusting the system's viscosity.

Another challenge may be the irritancy or toxicity of certain surfactants, particularly in cosmetics or household cleaning products. In such cases, it is recommended to choose milder alternatives, such as amphoteric or nonionic surfactants, and to conduct irritancy tests according to standard methods. In industrial applications, it is also important to ensure the stability of surfactants during storage—some may degrade at high temperatures or humidity. Prevention involves adhering to recommended storage conditions and conducting regular quality checks of raw materials.

4. How do REACH and CLP regulations affect the use of surfactants in industry?

The REACH regulation and CLP/GHS legislation have a significant impact on the use of surfactants in industry, particularly in terms of safety and environmental protection. REACH requires the registration of all chemical substances manufactured or imported into the EU in quantities exceeding one tonne per year, including surfactants. This means that manufacturers and distributors must provide detailed data on the properties, uses, and risks of each substance. For users, this ensures that the surfactants used meet strict safety standards and are accompanied by up-to-date safety data sheets.

The CLP/GHS Regulation then sets out rules for the classification, labelling and packaging of chemical substances, including surfactants. This includes the obligation to display warning symbols, standardised hazard statements (H-phrases) and safety instructions (P-phrases) on packaging. For industrial users, this means the need to adapt their processes and employee training to ensure that handling of surfactants complies with the regulations. It is also important to monitor updates to lists of substances subject to authorisation or restrictions, which may affect the availability of certain surfactants on the market.

Photo: RephiLe water / Unsplash

5. How do surfactants affect the environment and how to choose more eco-friendly options?

Surfactants are among chemical substances with a significant impact on the environment, particularly in terms of their biodegradability in aquatic environments and toxicity to aquatic organisms. Conventional anionic and nonionic surfactants, such as alkylbenzene sulfonates or alkylphenol ethoxylates, can persist and accumulate in ecosystems, leading to eutrophication of watercourses or disruption of biological processes. Therefore, it is crucial to select surfactants with a high degree of biodegradability, ideally certified according to standards such as the EU Ecolabel or Nordic Swan. These certifications guarantee that the substance will break down into harmless components within a short time and leave no long-term ecological footprint.

When selecting more environmentally friendly surfactants, focus on natural or bio-based alternatives, such as sugar-based surfactants (alkyl polyglucosides) or those derived from vegetable oils (e.g., fatty acid methyl esters). These substances not only exhibit lower toxicity but also often demonstrate better compatibility with other formulation components. It is also important to monitor the concentration of surfactants in the final product – optimizing dosage can significantly reduce environmental impact without compromising performance. In industrial applications where high efficiency is required, synthetic and natural surfactants can be combined to achieve a balanced ratio between performance and sustainability.

6. How to Store and Handle Surfactants Properly to Prevent Degradation or Loss of Effectiveness?

Storing surfactants requires adherence to specific conditions to maintain their stability and effectiveness. Most surfactants are sensitive to temperature fluctuations, humidity, and oxidation, so it is ideal to store them in sealed, original containers at temperatures between 10 and 25 °C. Extreme temperatures can cause phase separation, crystallization, or even chemical decomposition, particularly in nonionic surfactants with ethoxylated structures. For long-term storage, it is advisable to use containers made of non-reactive materials, such as stainless steel or high-density polyethylene (HDPE), which minimize the risk of contamination or reaction with the packaging material.

When handling surfactants, it is important to prevent contamination with water or other substances that could disrupt their structure. For example, anionic surfactants may react with metal cations (e.g., calcium or magnesium) to form insoluble precipitates, which reduces their effectiveness. It is recommended to use clean tools and equipment, ideally dedicated solely to working with surfactants. In the case of liquid surfactants, it is also advisable to check the homogeneity of the mixture before use, especially if they have been stored for an extended period. If separation occurs, gentle heating and stirring are possible, but always according to the manufacturer's recommendations to avoid degradation.

7. What innovations in surfactants are creating new opportunities for industrial applications?

Recent developments in surfactants focus on increasing efficiency, reducing environmental impact, and expanding application possibilities. One key innovation is the so-called gemini surfactants, which have two hydrophilic and two hydrophobic groups in a single molecule. Due to this structure, they exhibit a significantly lower critical micelle concentration (CMC) than conventional surfactants, meaning they are effective even at very low concentrations. This enables their use in demanding applications, such as high-pressure cleaning systems or emulsions with extreme stability, while reducing raw material consumption and costs.

Another trend is multifunctional surfactants, which combine several properties in a single molecule—such as wetting, emulsifying, and antistatic effects. These substances are used in industrial coatings, adhesives, or cosmetic formulations, where they reduce the need for multiple additives. Significant progress has also been made in the field of biosurfactants, which are produced through microbial fermentation or from renewable sources. These surfactants not only reduce dependence on fossil raw materials but often exhibit unique properties, such as resistance to extreme pH or temperatures, opening new possibilities for specialized industrial applications.

Do you have specific surfactant requirements?

Every application requires an individual approach. GCG Group provides detailed technical data sheets and safety data sheets (SDS) for supplied surfactants, including recommendations for storage, handling, and dosage optimization. Contact us with your requirements – we will advise you on selection and help solve technical challenges. Get in touch – or browse our catalog of over 1,300 products.