Removal of detergents and fats from waste water using allophane

Abstract

Micelles, consisting of an anionic surfactant and a fatty acid released from a fat, were removed from an aqueous phase using the ion exchange characteristics of a natural clay mineral, allophane. The UV spectral measurements revealed that the concentrations of the anionic surfactant and the fatty acid in the aqueous phase decreased and that these species were removed from the aqueous phase. The adsorption of the surfactant and the fatty acid onto the allophane was confirmed by FT-IR spectroscopy. Furthermore, this adsorption was confirmed by the adsorption of anthracene added as a probe molecule.

Removal of barium, cobalt, strontium and zinc from solution by natural and synthetic allophane adsorbents

“…Furthermore, one can see that 5-10 min is enough to achieve adsorption equilibrium under the experimental conditions used in this study, which indicates that physical adsorption rather than ion exchange contributes mainly to the removal of metal ions by natural and synthetic allophane adsorbents. This finding is in line with previous experimental results, where allophane has been successfully used in the remediation of aqueous solutions that were contaminated with, for example, heavy metals cations [15,22,33,35], metal (oxy)anions [18,23,30], heterocyclic organic components [10] and anionic surfactants and organic acids [17,23]. …”

“…Recently, agricultural and industrial waste products, activated carbon nanotubes, cellulose, carbonates, Feand Al-oxyhydroxides, zeolites, phosphates and clay minerals are used in the remediation of water that is severely polluted with persistent and hazardous components such as heavy metal ions, dyes, antibiotics, biocide compounds and other organic chemicals [12][13][14][15][16]. The use of clay minerals for wastewater treatment can be advantageous over other sorbents due to their worldwide occurrence, low mining and processing costs and outstanding physicochemical and surface properties, making clayey materials suitable for selective ion exchange, adsorption and catalyst uses [1,17,18].…”

“…Allophane "nanoballs" are characterized by a high surface area (> 300 m²/g). They are well-known to adsorb appreciable amounts of ionic or polar pollutants due to an amphoteric ligand exchange capacity [17,22,23]. To date, however, the sorption properties of allophane have not been effectively utilized in the remediation of wastewater.…”

Photoelectrochemical properties of dye-dispersing allophane–titania composite electrodes

“…The electrolyte for the photoelectric measurement consisted of a diethylene glycol solution of iodine (5.0×10 −2 mol dm −3 ) and lithium iodide (0.50 mol dm −3 ). The allophane (1.6SiO 2 ·Al 2 O 3 ·5-6H 2 O) was extracted by elutriation of Kanuma soil from Tochigi, Japan, as previously described (Nishikiori et al, 2009(Nishikiori et al, , 2010.…”

Reaction in photofuel cells using allophane–titania nanocomposite electrodes

“…Glass plates coated with the ITO transparent electrode (60 mm × 25 mm) (AGC Fabritec) were soaked in hydrochloric acid (1.0 mol dm 3 ) for 1 h and then rinsed with water. The allophane (1.6SiO2·Al2O3·5-6H2O) was extracted by elutriation of Kanuma soil from Tochigi, Japan, as previously described [23,25,26].…”