“…Unfortunately, research on pure water adsorption equilibrium is limited, in contrary to adsorption equilibrium of pure organic compounds (Chiang et al., 2001a, 2001b; Qi et al, 2006; Gironi and Piemonte, 2011; Lashaki et al., 2012; Nastaj and Chybowska, 2004; Ramirez et al., 2005; Wang et al., 2004, 2005). In literature, there are not many adsorption equilibrium data, especially on commonly used adsorbents such as various kinds of activated carbons (Kim et al., 2005; Nastaj and Aleksandrzak, 2013; Qi and LeVan, 2005a,b; Qi et al, 2006). There are several models describing pure water adsorption equilibrium (Do, 1998; Ladshaw et al., 2015; Qi and LeVan, 2005a,b; Ribeiro et al., 2008; Talu and Meunier, 1996; Tien, 1994).…”