Remediation of heavy metal ions utilizing collophane

Kinetic research on the sorption of aqueous lead by synthetic carbonate hydroxyapatite

“…As far as the latter is concerned, such minerals as zeolite (Chlopecka and Adriano, 1997;Chang et al, 2004a, b;Pitcher et al, 2004;Ö ren and Kaya, 2006), goethite (Trivedi and Axe, 2001;Mustafa et al, 2004;Pohlmeier and Lustfeld, 2004;Lackovic et al, 2004), magnetite (Stipp et al, 2002;Chang et al, 2004a, b;Martı´nez et al, 2004), perlite (Alkan and Dogan, 2001;Dog˘an et al, 2004;Acemiog˘lu, 2005) and so forth, are used to resolve various environmental pollutions. Apatites have been the object of considerable attention (Miyake et al, 1990;Jeanjean et al, 1996;Chen et al, 1997a, b;Fuerstenau et al, 1997;Admassu and Breese, 1999;Manecki et al, 2000;Mavropoulos et al, 2002;Arnich et al, 2003;Mavropoulos et al, 2004;Go´mez del Rı´o et al, 2004;Peld et al, 2004;Lee et al, 2005;Raicevic et al, 2005;Knox et al, 2006) because of their peculiar crystal-chemistry characteristics, and it has been proposed that they can be used to remove heavy metal ions, including lead, from contaminated wastewaters (Mavropoulos et al, 2004). They can also be used as a barrier to minimize heavy metal migration from heavymetal-containing solid wastes or soils (Chen et al, 1997a, b).…”

Single, binary, and multicomponent sorption of iron and manganese on lignite

“…Due to the expense of carbon for water treatment, a search for tailor-made adsorbents/substitutes is underway. Investigators have studied less expensive materials for the removal of Fe(II), Fe(III), and Mn(II) from water, such as fly-ash-based zeolites [37,38], activated sludge [39], cellophane [40], hydrous manganese dioxide [41], hematite [42], palm fruit bunch and maize cob [43], rice husk [2], and zerovalent iron [44], for metal ion removal. Numerous other efforts made in this direction are described in various review articles [45,46].…”

Utilisation of phosphatic minerals as pollution sorbents for removal of heavy metals from aqueous solutions

“…The results clearly demonstrate that the separation process for Cu and Co ions, in terms of amount adsorbed and percentage removal is significantly improved in neutral and alkaline (pH 6-12) medium rather than the acidic solutions (pH 2-4). For example, lower percentage removal (y66%) of Cu ions is recorded in the acidic pH (2-4) range while in the alkaline region (pH 8-12), (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). These results illustrate that adsorption process for these heavy metal ions could be correlated to the zeta potential of the surface of the sorbent and its solubility in addition to the presence of different hydrolysis products of heavy metals with changing pH.…”

“…[2][3][4] Apatite minerals (hydroxyapatite and fluorapatite) have been tested for the removal of heavy metal ions such as lead, zinc and cadmium both collectively and separately in aqueous solutions using sorption techniques. [5][6][7] Also, clay minerals such as pyrophyllite, and low grade rock phosphate available in Madhya Pradesh (India) have been investigated recently as possible sorbents for attenuation of aqueous lead ions. [8][9][10] It should be mentioned that both phosphate and clay minerals are also available in large reserves in Egypt.…”