Dye‐affinity microbeads for removal of phenols and nitrophenols from aquatic systems

Abstract

Alkali Blue 6B attached poly(2-hydroxyethyl methacrylate) (PHEMA) microbeads were investigated as dye-affinity adsorbents for the removal of phenol and nitrophenols (i.e., 2-nitrophenol, 4-nitrophenol, and 2,4-dinitrophenol) from aqueous solutions. PHEMA microbeads were prepared by radical-suspension polymerization of HEMA in the presence of azobisisobutyronitrile as the initiator. These microbeads with a swelling ratio of 55% and carrying 23.6 mol Alkali Blue 6B/g polymer were then used in the removal of phenol and nitrophenols from aqueous media. The adsorption was fast in all cases (20-min equilibrium time). The maximum adsorptions of phenols onto the microbeads carrying Alkali Blue 6B were 145.2 mol/g for phenol, 87.8 mol/g for 2,4-dinitrophenol, 112.6 mol/g for 4-nitrophenol, and 104.3 mol/g for 2-nitrophenol. The affinity order was phenol Ͼ 4-nitrophenol Ͼ 2-nitrophenol Ͼ 2,4-dinitrophenol. The adsorption of nitrophenols decreased with increasing pH. Desorption of nitrophenols was achieved using a 30% (v/v) methanol solution. The microbeads carrying Alkali Blue 6B are suitable for repeated use for more than five cycles without a noticeable loss of adsorption capacity.

Methacrylate‐based chromatographic media

“…Reactive dyes like Cibacron Blue F3GA, Alkali Blue 6B, and Procion Red HE3B, which have originally been developed for permanent coloration of cotton fabrics, react readily with hydroxyl groups of synthetic polymethacrylate beads [146, 152 -154]. These immobilized dyes also enable removal of phenols and nitrophenols as well as heavy metal ions from aqueous solutions [155].…”

Adsorption of phenol and its derivatives from water using synthetic resins and low-cost natural adsorbents: A review

“…The cibacron blue F3GA-carrying microbeads are suitable for repeated use for more than five cycles without any noticeable loss of adsorption capacity. Besides, they also used PHEMA microbeads as the dye-affinity adsorbents for the removal of phenol, 2-NP, 4-NP, and 2,4-DNP from aqueous solutions (Denizli et al, 2002). The PHEMA microbeads were prepared by radical-suspension polymerization of HEMA in the presence of azobisisobutyronitrile as the initiator.…”

Sorption onto insoluble β-cyclodextrin polymer for 2,4-dinitrophenol

“…8 (Inset), the maximum adsorption capacities of the polymer toward 2,4-DNP: q max = 192 mg/g it's indicating that the polymer adsorbed 2,4-DNP considerably. In several authors have been reported the different verities of materials (carbon) AP-32 carbon (apricot stone shell) [27], Prolabo (Charcoal activated powder) [27], GAC (granular activated carbon) [28], PHEMA microbeads [29], Bentonite [30], Paper mill sludge [31], Phanerochaete chrysosporium biomass [32], Palm pith carbon [33], Coir pith carbon [34], Fly Ash [35], Coal Fly Ash [36], Agedrefuse in biofilter [37] are able to adsorb the 2,4-DNP. These data are listed in Table 2 and from the Table 2, the b-CD polymer having very good adsorption capacity.…”