Bath researchers develop energy efficient membrane for solvent purification

A TEAM of researchers from the University of Bath and an international research group KU Leuven have developed a membrane to drive out water in the development of industrial solvents.

In the face of Europe’s ever-growing production restrictions on energy-intensive chemical production methods, the team developed the membrane to help reduce the energy use needed to purify industrial chemicals, in this case isopropanol.

Isopropanol is a fast-evaporating solvent used in surface disinfectant, first-aid antiseptic and elsewhere in the pharmaceutical industry.

Separating chemicals requires a lot of energy because of the heat needed to boil off impurities and isolate compounds, with research reporting that the process accounts for 10 to 15% of global energy use.

The research team developed a new type of membrane using graphene oxide, a material of ultra-thin carbon layers with pores large enough to let molecules to pass through without the need for high energy usage, but small enough to maintain the purity standards needed for industrial chemicals.

Pengrui Jin, a researcher at Bath’s Department of Chemical Engineering and the independent principal investigator of the study, said that the membrane was able to efficiently remove water from a mixture containing 90% isopropanol and 10% water.

She added: “It selectively transports the water through the membrane, producing a permeate containing about 99.6% water. In addition, the process is faster than existing techniques and requires less energy as it does not rely on high temperatures.”

The researchers are looking to test the membrane technology on other chemicals while also looking at the possibility of filing a patent for it to explore scale-up opportunities.