“…Membrane technology plays an important role in various environmental and energy processes, such as CO 2 capture (Zou and Ho, 2008;Hussain and Hägg, 2010;Brunetti et al, 2010;Yang et al, 2008), biogas upgrading (Deng and Hägg, 2010;Makaruk et al, 2010;Pakizeh et al, 2013;Momeni and Pakizeh, 2013), natural gas sweetening (Bernardo et al, 2009;Peters et al, 2011;Baker and Lokhandwala, 2008), and hydrogen production (Sà et al, 2009;Clem et al, 2006) and can potentially compete with some traditional separation methods in terms of energy requirements and economic costs (Xuezhong and Hägg, 2012).…”