Nanoarchitectonics of a Smectite with 4,4′-Diammonium-α-truxillic Acid and Its Methyl Ester for the Removal of o-Phenylphenol and Biphenyl from Water

Adsorbents with hydrophilic and hydrophobic natures were designed by intercalating a bioderived molecule; 4,4'-diammonium-α-truxillic acid (4ATA) and 4,4'-diammonium-α-truxillic acid dimethyl ester (E4ATA), which both are bioderived molecules, into a smectite (purified bentonite) to concentrate o-phenylphenol and biphenyl, respectively, from water. The adsorption isotherm showed high affinity between the 4ATA-smectite hybrid and o-phenylphenol with a high Langmuir constant (0.98 L mg^-1). Meanwhile, the E4ATA-smectite hybrid adsorbed biphenyl with a high Langmuir constant (3.61 L mg^-1). The adsorption properties of 4ATA- and E4ATA-smectite hybrid were contributed by the chemical characteristics of 4ATA and E4ATA in the interlayer space of the smectite.