Research

The team is researching the application of organic solvent nanofiltration membranes as a continuous unit operation in typical pharmaceutical processes such as active pharmaceutical ingredients (API) synthesis, API purification and solvent exchange, API crystallisation, crude oil refining and others.

Isothermal Refining by Organic Solvent Nanofiltration 

We are researching the use of membranes for refining crude oil to enable significant reductions in energy requirements for manufacturing fuels and lube products from crude oil. Current oil refinery technology is based on distillation for separation of the crude oil into fractions with varying molecular weights, followed by further reactions on some of these fractions (reforming, hydrotreating, cracking etc), which must then be further distilled. In refining, distillation typically account for more than half of all the energy consumed, since the phase change on boiling requires significant energy input. One way of avoiding this large energy consumption would be to carry out fractionation in the liquid phase via a membrane.

The majority of membrane separations to date are water based. Membranes are not generally used for molecular separations in organic systems, because until recently there were few membranes stable in organic liquids. This has changed recently - research at Imperial College has developed membranes that are stable in most organic systems. These have been commercialised through an Imperial spin out company, Membrane Extraction Technology (MET) which was acquired by Evonik Industries on 1 March 2010. 

The project will work closely with partner Shell Global Solutions.

The research team is currently developing better methods for designing membranes tuned for specific applications in the energy industry. Predicting and ensuring membrane lifetime performance is critical for efficient and reliable water operations that use reverse osmosis. We are working on the fabrication of thin film composite membranes made by interfacial polymerization and the supports for these membranes. 

BP-International Centre for Advanced Materials (BP-ICAM) 

The Livingston Group is a founding member of BP-ICAM and leads a project which seeks to understand at the atomic level, the structure and mechanisms of membranes and to use this understanding to develop models that can better predict the behaviours of membranes in practical applications. Reverse osmosis (RO) is currently used to adjust the water salinity used in the flooding of oil reservoirs and adjusting membrane properties has the potential to enhance oil recovery.

The project aims to:

For more information about ICAM please visit the ICAM website.

Our research team is aiming to develop a new manufacturing process for making high value sequence-controlled polymers in a precise way. Sequence-controlled polymers include (bio)polymers such as DNA, RNA (together, "oligos") and peptides. They also include synthetic polymers for which precise control of polymer length or monomer order is necessary. These polymers are in demand by the pharmaceutical industry, where they are used as biologically active materials ("drugs"), and as parts of molecular assemblies that are used to deliver and protect drugs; and have emerging non-biological uses.

Iterative Synthesis with Organic Solvent Nanofiltration for Precision Manufacture of High Value Sequence-Controlled Polymers

Nature makes sequence-controlled polymers such as oligos or peptides by sequentially adding different monomers in a prescribed sequence. The exact order of that these monomers are added is absolutely crucial to the function of the final polymer. These same polymers are made by industrial chemistry in a way that apes Nature, through a sequence of monomer additions (we call this iterative synthesis), and a great deal of care is taken to remove the residues of unreacted monomer before the next cycle, to avoid errors in the sequence.

A very effective way of doing this is to attach the growing polymer to a solid support phase, which is washed with clean solvents to remove the residues, before the next monomer is added. When polymer growth is complete, it is cleaved from the solid support. However this process is expensive, because more monomer must be used to ensure the reaction reaches completion on the solid support, and because the supports themselves are expensive. For synthetic polymers where we want to control the molecular weight exactly, for example poly(ethylene glycols) (PEGs), which are widely used to stabilise drugs and make them last longer in the body, we could add the same monomer over and over until we reach a desired chain length, and then cleave the final polymer from the support. This is not done at present, because the cost of solid supported iterative synthesis is too high and/or the chemistry is not available.

There are other problems with solid supported synthesis. The solid supports are variable, and hard to make in a precisely repeatable way; in fact small differences in the supports can lead to quite big changes in the reactions used to link the monomers onto the growing polymer. Also, it is very hard to carry out analyses on the reaction mixture to tell whether the reactions are proceeding correctly, because the molecules of interest are inside the pores of a support material.

The multidisciplinary team of chemical engineers and chemists within the project are developing the process chemistry to improve the purification; construct Lab Plant synthesisers so that the process can be automated, select solvents and explore solvent recovery, and use quality by design to make the process more efficient. If we are successful, the project will result in a new technology for sequence-controlled polymer manufacture, and will lead to more precise polymers being available for applications in healthcare and beyond.

SynFabFun

The team works extensively on the use of membrane separations in solvent systems where they are able to provide new routes to catalyst recycle, product separation, and solvent operations. The Group has successfully developed organic solvent nanofiltration (OSN), using membranes that are stable in solvents, and able to separate small molecules from large molecules

SynFabFun 

The Livingston Group is part of an EPSRC-supported virtual membrane centre SynFabFun – from membrane material synthesis to fabrication and function –  which brings together experts from the universities of Newcastle, Bath, Imperial, Edinburgh and Manchester to develop and implement new membrane systems and techniques. The five-year project, led by Newcastle University, will explore the potential of new materials to replace existing industrial membrane systems in four main industry sectors: energy, manufacturing, pharma and water. To prove their reliability, the researchers will subject the membranes to the equivalent of 30 years of use in a shorter timescale through the development and use of accelerated ageing tests, employing membranes at higher temperatures and in the presence of higher concentrations of poisons that they would otherwise experience. Their aim is to develop an immortal membrane – or at least, one that will outlive the lifetime of the industrial plant or  equipment where it is being used. Another key aim is to develop a low-energy technology.

“The membrane separation of molecules from organic solvents would result in very significant energy savings," explained project lead Ian Metcalfe, Professor of Chemical  Engineering at Newcastle University. "Hydrogen and/or carbon dioxide removal from a water-gas shift process in-situ – over a range of temperatures depending upon the nature of the membrane – could change the way we produce hydrogen. In terms of organic membranes we are seeking to work on systems that are already in a relaxed or equilibrium state. Such membranes cannot lose permeance as they evolve towards some equilibrium structure. For inorganic membranes we will study – for example – routes to self-healing membranes using techniques such as secondary wetting phases. We will also study hybrid membranes where for example we can introduce two permeation pathways, one for carbonate ions and one for oxygen ions, with the net outcome of a carbon dioxide permeable membrane. Such membranes would allow carbon dioxide permeation under conditions not available to organic membranes.”