Elimination of dyes from aqueous solutions using iron oxides and chitosan as adsorbents: a comparative study

Abstract

Recebido em 5/9/08; aceito em 4/12/08; publicado na web em 7/5/09This work investigates the adsorption of Alizarin, Eriochrome Blue Black R and Fluorescein using chitosan, goethite and magnetite as adsorbents. For Alizarin, the best adsorbent is chitosan with a Langmuir parameter of 15.8 mmol dye/g adsorbent. For Eriochrome Blue Black R only 1.94 mmol dye/g chitosan is adsorbed. Langmuir parameters for the Alizarin adsorption on both iron oxides display one or two orders of magnitude lower than for chitosan and two orders of magnitude lower in the case of Eriochrome Blue Black R. Fluorescein does not adsorb in appreciable amounts on chitosan and it presents the lower affinity on the iron oxides.

Magnetically modified natural biogenic iron oxides for organic xenobiotics removal

“…confirm this statement (Pirillo et al 2009). The comparison of magnetic biogenic iron oxides (a typical representative of ''inorganic biosorbents'') with recently developed magnetically responsive biosorbents is shown in Table 4; again, all the magnetic biosorbents are comparable from the point of view of maximum adsorption capacities.…”

Epicarp and mesocarp of babassu (Orbignya speciosa): characterization and application in copper phtalocyanine dye removal

“…8 Investigations have recently been directed to alternative sorbents, also known as low-cost or unconventional, based on both the environmental and the economical points of view. [9][10][11][12][13][14][15][16][17][18][19][20] In order to overcome high cost problems, an increasing interest in producing new alternative sorbent materials to replace the most used activated carbon has been raised, also taking into account local availability, since these new materials are frequently constituted of residues from agricultural activity or sea food processing. 21 Brazil has a high potential for lignocellulosic fiber production.…”

Performance evaluation of two stage nanofiltration for treatment of textile effluent containing reactive dyes

“…3(a) shows use of NF membrane results to the rejection of dye molecules up to 88%. Acidic dyes always remain in anionic state because of their low pK a value and presence of negatively charged sulfonic groups [43,44]. The membrane has negative zeta potential (see Table 2) at pH 11.2.…”