Cleaning secondary effluents with organoclays and activated carbon

Abstract

BACKGROUND: Flocculation, adsorption and ultrafiltration, alone and in combination, were tested for tertiary treatment of Beer Sheva (southern Israel) municipal wastewater. The focus was on the adsorption of soluble organics with powdered activated carbon (PAC) and with organoclays.

Clay Materials for Environmental Remediation

“…The most common cationic surfactants used for clay modification, are quaternary ammonium salts, such as CTAB (Yilmaz and Yapar 2004;Ma et al 2010;, ODTMA (Hedley et al 2007;Huang et al 2007;Siebdrath et al 2012), TMA (Siebdrath et al 2012), TMAB (Yilmaz and Yapar 2004;Singla et al 2012;, DTAB (Singla et al 2012), HDTMA (Anirudhan and Ramachandran 2007), and other . Even though the cationic surfactants are not good detergents nor foaming agents, these substances still widely employed as modifying agents for clay modification due to their positive charge.…”

Organic fouling and floc transport in capillaries

“…However, the high cost of the common adsorbent powdered activated carbon (PAC) prevents the exploitation of the technology on a daily basis. Unfortunately the lower-cost alternatives, such as wood shavings [20], coconut shells, chitin, chitosan [21], fly ash [22], lignin [23], or natural clays [24], are failing to retain the low-molecular-weight hydrophilic compounds and cannot replace the PAC at the moment.…”

Pairing micropollutants and clay-composite sorbents for efficient water treatment: Filtration and modeling at a pilot scale

“…The sorptive properties of surfactant based clay composites (Boyd et al, 1988;Jiang et al, 2002;Rathnayake et al, 2015) and of polymer clay composites (Churchman, 2002;Liu, 2007) have been described. The use of such clay composites for the removal of inorganic pollutants (Şölener et al, 2008), effluent dissolved organic matter (DOM) (Siebdrath et al, 2012), organic pollutants such as dyes (Margulies et al, 1988;Rytwo et al, 1995;Szabo et al, 2011), herbicides (Carrizosa et al, 2000;Cruz-Guzmán et al, 2004;Nir et al, 2000) and pharmaceuticals (Anggraini et al, 2014), have been reported (Park et al, 2011) as well. These studies demonstrate pollutant adsorption in suspension, but recently the employment of optimal sorbents in filtration columns has gained growing interest.…”