F3 Factory Case Study: Intensified Reaction Technology for Surfactants

Achieving step-change process intensification in the production of anionic surfactants was the primary goal of the Procter & Gamble (P&G) industrial case study. Working with project partners the Institute of Chemical Process Fundamentals (ICPF), Britest and Karlsruhe Institute of Technology (KIT), the project focused on the intensification of two key reactions stages (S0₂ oxidation and sulphonation) using novel reaction technology and modelling of the economic viability of the concepts in the latter stage of the project.

As one of the world’s leading consumer products businesses P&G is one of the largest global manufacturers of surfactants. With no major developments in surfactants production technology for decades, potential gains from the novel F³ Factory approach could be significant.

The current business model is to produce bulk surfactants at large-scale, centralised locations and then ship to finishing sites. A step change in the base technology could lead to differentiated supply chains including more distributed, less transport-intensive scenarios and reduced business risk.

In changing the operating strategy for anionic surfactants, P&G is seeking to unlock the benefits of flexibility, agility and long-term sustainability.

Technological developments

Process intensification is seen as the main lever available to progress the supply chain to a more sustainable and lower cost model. Concentrating on the two unit operations is essential to an overall step change; therefore, the project has focused on SO₂ oxidation and sulphonation.

The size and inertia of current SO₂ oxidation towers negatively impacts on the whole plant agility. In addition, due to limited use of intensification, sulphonation forces the dilution of SO₃ with large amounts of air. This markedly increases the plant’s capital, volumetric and environmental footprint.

Proof-of-concept work focused on:

• obtaining targeted lab scale information on oxidation of SO₂ in micro-channel settings
• identifying technical intensification strategies for sulphonation
• development of two new reactor designs

The project team investigated the concept of a microstructured reactor with an adiabatic section at the beginning of the reactor beginning and one cooling section at the rear of the reactor. Based on experimental measurements of kinetics, simulations of the reaction kinetics and heat transfer; a new reactor design with two parallel microstructured reactors was developed (see below).

The project team also investigated the concept of a new intensified device for sulphonation. The experimental study focused on hydrodynamic behaviour of lab scale equipment in a wide range of operating conditions. The pressure drop and heat transfer coefficient were determined and an adequate correlation developed.

The sulphonation process on the lab scale reactor prototypes, that were designed and manufactured at ICPF in Prague, was tested during the demonstration phase of the project in P&G’s pilot plant facility in Brussels. This intensified sulphonation process developed new learning, which may help in further intensifying current reaction systems.

What, when, where

The F³ Factory programme has been a unique collaborative endeavour that could stimulate the transition to a new business model for the whole chemical sector.  In this new model flexible, modular, continuous and intensified technologies are used to meet the challenge of producing “what’s needed, when needed, where needed” therefore minimising the environmental and economic footprint and reducing business risk.

For the P&G case study, intensification of two key reactions stages (S0₂ oxidation and sulphonation) in the production of anionic surfactants using novel reaction technology was largely proven at the lab scale. The challenge going forward will be to prove the economic viability of modular production technologies on highly optimised, large scale surfactants manufacture.

More information

For more information visit the F3 Factory Project website or contact Diederik Vanhoutte at P&G.