Removal of Azo dyes with Xanthan

Abstract

The interaction among Xanthan (XANT) and three azo dyes: Direct blue 1 (DB1), Direct red 81 (DR81), and Direct black 22 (DB22) was studied. The Xanthan-dye-Al product was formed after the addition of AlCl3 to a Xanthan-Dye adduct containing solution. It was proposed that polyhydroxyoxoaluminum clusters named CAL-13 and CAL-30 react with this adduct producing a Xanthanate aluminum network, XANT-Al, and as a consequence a decrease in dye concentration in an aqueous medium was observed. The removal efficiencies obtained were the following: DB1 (99 %), DB22 (99 %) and DR81 (94 %), demonstrating that this dye removal method is very efficient. The Zimm-Bragg model adequately described the experimental data and the order observed in the Ku (nucleation) and U (aggregation) parameters from this model was the following: DB1>DB22> DR81. Evidence suggests that physicochemical properties of dyes such as charge, molecular weight, aggregation ability and the capacity of XANT-Al to trap dye molecules are involved in the high removal values. Moreover, the dye binding mechanisms include: electrostatic, hydrogen bonding and hydrophobic interactions that determine the magnitude of the parameters Ku and U. These findings suggest that the XANT polymer is a good option to remove azo dyes from an aqueous medium.

Polyamidoamine‐Based Hydrogel for Removal of Blue and Red Dyes from Wastewater

“…In particular, as regards DB, the stretching of aromatic moieties with the contribution of CN stretching appears in Figure B at 1587 and 1481 cm −1 , respectively. At around 1220 cm −1 , the CN stretching with the contribution of the NH bending was detected . In the 1550–1650 cm −1 wavenumber region, a band was observed at 1611 cm −1 , indicating the CO stretching vibration mode present in the DB molecular structure .…”

A Stochastic Model for Adsorption Kinetics

“…Therefore, the mean function (20) of the TOU model matches the PNO model (3). In this sense, the PNO model is a particular case of the TOU model, whenever σ = 0.…”

“…Recently, various biomaterials and their derivatives have been used to remove different pollutants from aqueous media. In the case of dye removal, biopolymers such as chitin, chitosan, xanthan, alginic acid, and pectin have been applied [20,[30][31][32][33][34][35]. In this study, Pec-Ca synthesized in our laboratory was used to remove DR80 and DB1 dyes, whose structures are shown in Figure 2.…”

“…The proposed TOU model ( 16) has the advantage of including a variability component, which explains the dispersion of the kinetics around the mean function (20). In this way, from expressions ( 18)-( 21), the natural uncertainty in the adsorption process is represented as the variance…”

A comprehensive investigation of dye–chitosan blended films for green chemistry applications

“…However, the presence of hydrogen bonds between DB and chitosan chains, due to the partial deprotonation of amino groups, cannot be excluded, indicating that the driving force of the adsorption process was not only attributable to electrostatic interactions but also to hydrogen bonds and hydrophobic interactions. To infer more information, the IR spectrum of DB was collected [see Figure (a)], and the detailed description is reported in the Supporting Information. Unfortunately, the typical bands of DB were not detected in the chitosan blended films [Figure (b,c)], and this behavior could be ascribed to two factors.…”