Low-cost Membrane Easily Separates Light and Heavy Oil from Water

Published Date : May 28, 2018

A new low-cost membrane developed by researchers from the University of British Columbia has demonstrated the capability of effectively separating water and oil on demand, a discovery that could set the stage for better solution to more effective treatment of industrial wastewater and much faster cleanup of oil spills.

The new membrane is made of a treated copper mesh that can, by the simple application of only a few seconds worth of power from a conventional battery, can switch from water-removal to oil-removal mode. When the mesh is operating in the water-removal mode, it retains light oil while allowing water to pass through; when working in the oil-removal mode, the mesh retains water while allowing heavy oil to pass through. Thus consecutively switching between the two modes can easily allow the removal of light as well as heavy oils from water with the use of a single membrane.

Researchers note that the technology is an effective and environment friendly way of reducing the negative impact of oily wastewater and water on ecosystems that are subjected to such waters, massive volumes of which are incessantly created by industrial, municipal, and even domestic processes every day. Conventional oil-water separation mechanisms such as the ones that rely on solvents, combustion, and skimming are either very costly, largely inefficient, or very tedious.

While other membrane treatments capable of switching from water to oil removal exist, most rely on unstable and toxic chemical coatings that also require time for activation. Moreover, they tend to produce products that need further processing. On the other hand, the new membrane is does not have additives and can achieve nearly 98% purity for the water and oil that are separated with the help of it.