316 250 2,500-67,000 6.5 97 5 99 0.3-3 Díaz , 2011; Rodríguez , 2012 Jenicek , 2010; Jenicek , 2011 550 Pressure swing adsorption, PSA 92-98 32 0.07 46 0.1 100 67 0.1 100