Polymer membranes have become a leading contender in numerous separation processes. Be it in gas (air, hydrogen etc.) or be it in water purifications (salinated water, waste water etc.). Not only polymer membrane technology helps reducing the environmental impact but also it is cost-effective. Fracking in shell gas is one of many examples. New advances in drilling technology (such as horizontal drilling) have led to new hydraulic fractures called fracking. Hydraulic fracturing requires about 2.5 to 5 million gallons of water per well. Water management and its disposal are major costs for producers.
One major challenge, however, of the membrane technology is the fouling (damage caused by contaminants) mitigation. This has been recently studied by a group of researchers from University of Texas at Austin led by Professor Benny Freeman to address efficiency and reuse of water for fracking in shale gas plays.
Researchers modified polydopamine coated UF (ultrafiltration) module by grafting polyethylene glycol brushes onto it. The result is more hydrophilic surfaces which in turn improved cleaning efficiency relative to unmodified modules. The coating improves the membrane life, and can easily be applied to membrane surface by rinsing it through the recycling system.
[References: D.J. Miller, X. Huang, H. Li, S. Kasemset, A. Lee, D. Agnihotri, T. Hayes, D.R. Paul, and B. Freeman; J. Membrane Sci., 437, pp. 265-275 (2013); Also see www.advancedhydro.net ]