Engineering Surfactant Powders: Drying Dynamics, Structure and Performance

About the Project

Surfactant powders are everywhere, from household detergents to industrial formulations, but their performance is ultimately determined by how they dry. Alpha-olefin sulfonates (AOS) are widely used anionic surfactants, valued for their robustness and versatility, yet the fundamental links between formulation, drying dynamics, and final powder performance remain poorly understood. Drying is a highly dynamic process, involving evolving concentration gradients, interfacial phenomena, and phase transitions that shape particle morphology, internal structure, and dissolution behaviour. Gaining control over these processes is key to designing better-performing, more efficient surfactant products.

This collaborative PhD project, supported by the University of Leeds and Innospec, offers the opportunity to uncover the science that governs how surfactant powders form. The project will deliver new mechanistic insight into AOS drying, connecting formulation chemistry and processing conditions to structure and performance, with direct relevance to industrial manufacturing.

At the heart of the research is a unique acoustic levitation platform that allows individual droplets to be dried without contact, enabling real-time observation of shape changes, crust formation, and internal structural evolution. This will be combined with state-of-the-art small- and wide-angle X-ray scattering (SAXS/WAXS) to probe nanoscale structure development during drying, including phase transitions and crystallisation. Time-resolved synchrotron SAXS experiments at Diamond Light Source will provide an exceptional window into how droplets transform from liquids into hollow or solid particles. These insights will be linked to key macroscopic properties such as particle morphology, dissolution rate, and rehydration behaviour.

The student will be based in the School of Chemical and Process Engineering (SCAPE) at the University of Leeds and supported by a highly interdisciplinary supervisory team spanning chemical engineering, mechanical engineering, food science, and industrial formulation science. The project offers access to world-leading experimental facilities, pilot-scale drying equipment, and close industrial collaboration with Innospec, including the opportunity for an industrial placement.

Alongside advanced technical training, the student will benefit from the EPSRC Doctoral Landscape Award, gaining professional and transferable skills, research ethics training, and opportunities for conference participation and international collaboration. This PhD is ideal for a motivated candidate seeking hands-on experimental research, strong industry engagement, and the chance to make a real impact at the interface of formulation science, manufacturing, and materials physics.

Funding Notes

A highly competitive EPSRC Faculty Doctoral Landscape Award, in collaboration with Innospec, providing full academic fees, together with a tax-free maintenance grant at the standard UKRI rate of £21,805 for 3.5 years. Training and support will also be provided. This opportunity is open to UK applicants only. All candidates will be placed into the EPSRC Faculty Doctoral Landscape Award Competition and selection is based on academic merit.