Surfactants in action: chemistry, behavior, and industrial applications

Abstract Surfactants, or surface-active agents, are multifunctional amphiphilic compounds essential across numerous industrial and domestic applications. This review provides an in-depth analysis of surfactant chemistry, focusing on their diverse structures, interfacial behaviors, and self-assembly mechanisms, including micelle formation and emulsification. It outlines the classification of surfactants – anionic, cationic, non-ionic, and zwitterionic – while also exploring innovative types such as biosurfactants, sugar-based, lignin-derived, algal-based, and gemini surfactants. The growing emphasis on environmentally friendly and biodegradable surfactants sourced from renewable materials is highlighted, reflecting a shift away from conventional petroleum-derived options. The review examines key properties like surface tension reduction, wettability enhancement, foaming, detergency, and emulsification, linking them to their wide-ranging applications in sectors such as petrochemicals, pharmaceuticals, nanotechnology, paper manufacturing, and biotechnology. Finally, it underscores the crucial role of surfactants in fostering sustainable advancements and their potential for driving future technological innovations.