Researchers from Qatar develop a unique method for separation of oil-water mixtures

Water is the essence of life and maintaining clean water sources has always been seen as a foremost priority in Qatar and worldwide. However, the safety of our water sources is under constant threat and often compromised. Oil spills and related accidents are a growing challenge that seriously damage and threaten aquatic environments and cause environmental imbalances that lead to heavy human, economic, and environmental costs.

Due to the severe hazards that the oil leakages create, innovative methods must be developed to separate oil from contaminated water. Similarly, technologies for oil-water separation also have large-scale applications in the various petrochemical industries that face the critical challenge of treating the produced water byproduct as very minute quantities of oil need to be separated.

To address this rising need, a team of researchers from Qatar University (QU) has developed innovative nanostructured membranes that can efficiently absorb and separate oil from oil-water mixtures and emulsions. Led by Prof. Mariam Al-Maadeed, vice president for research and graduate studies, and founder and former director of the Center for Advanced Materials at QU, the team has designed the polymer-based membranes to be durable, self-cleaning, and recyclable. The project titled, ‘Nanostructured Membranes for Oil-Water Separation,’ (NPRP10-0127-170269) received funding under the tenth cycle of Qatar National Research Fund’s flagship National Priorities Research Program.

These membranes can efficiently produce filtrate of pure water due to the use of nano-reinforced block copolymer (BCP) membranes, which exhibit a highly ordered periodic and uniform pore size ~ (10-100) nm with ultrahigh pore density.  BCPs are a viable choice as filtration membranes due to their unique characteristics including directed self-assembly, domains’ vertical orientation, and great ability to control porosity.

The developed membranes can be used in two main ways including packings and media filters which selectively absorb the oil from an oil-water emulsion or as an ultrafiltration membrane, which separates oil and water from the mixture with applied pressure. Both these techniques result in pure water formation as the filtrate.

To further improve the membranes, the team added nanoparticles to it to enhance the hydrophobicity (the property of being repellant to water) and oil absorption capacity of the membranes. The incorporation of nanoparticles also builds the mechanical performance of the membrane and increases its antibacterial properties to address the issue of biofouling (accumulation of microorganisms, plants, and small animals which can cause functional and structural problems).

Along with researchers from Qatar University, the project includes experienced researchers and industry professionals working in the fields of polymers and membrane testing from the University of Houston and ConocoPhillips Qatar. Owing to its successful outcomes, the project has been featured in numerous research publications and hailed as a success story in the ongoing efforts in Qatar for ensuring water safety which have received worldwide recognition and acclaim.