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Removal of Direct Orange 26 azo dye from water using natural carbonaceous materials

Kuśmierek Krzysztof, Dąbek Lidia, Świątkowski Andrzej

Archives of Environmental Protection

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2023

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Vol. 49, no 1

47--56

EN

The aim of the study was to assess the possibility of using natural carbonaceous materials such as peat, lignite, and hard coal as low-cost sorbents for the removal of Direct Orange 26 azo dye from an aqueous solution. The adsorption kinetics and the influence of experimental conditions were investigated. The following materials were used in the research: azo dye Direct Orange 26, Spill-Sorb “Fison” peat (Alberta, Canada), lignite (Bełchatów, Poland), and hard coal (“Zofiówka” mine, Poland). The morphology and porous structure of the absorbents were tested. Dye sorption was carried out under static conditions, with different doses of sorbents, pH of the solution, and ionic strength. It was observed that the adsorption of Direct Orange 26 dye on all three adsorbents was strongly dependent on the pH of the solution, while the ionic strength of the solution did not affect the adsorption efficiency. The adsorption kinetics were consistent with the pseudo-second-order reaction model. The stage which determines the rate of adsorption is the diffusion of the dye in the near-surface layer. The process of equilibrium adsorption of Direct Orange 26 dye on all tested adsorbents is best described by the Langmuir isotherm. The maximum adsorption capacity for peat, brown coal and hard coal was 17.7, 15.1 and 13.8 mg/g, respectively. The results indicate that peat, lignite, and hard coal can be considered as alternative adsorbents for removing azo dyes from aqueous solutions.

PL

Celem pracy była ocena możliwości wykorzystania naturalnych materiałów węglowych takich jak torf, węgiel brunatny i węgiel kamienny jako niskokosztowych sorbentów do w usuwaniu barwnika azowego Direct Orange 26 z roztworu wodnego. Zbadano kinetykę adsorpcji oraz wpływ dawki sorbentu, pH roztworu oraz siły jonowej na skuteczność sorpcji. W badaniach wykorzystano barwnik azowy Direct Orange 26, torf Spill-Sorb „Fison” (Alberta, Kanada), węgiel brunatny (Bełchatów,Polska) oraz węgiel kamienny („Zofiówka”, Polska). Wykonano badania morfologii oraz struktury porowatej absorbentów. Sorpcję barwnika prowadzono w warunkach statycznych, przy różnych dawkach sorbentów, pH roztworu i sile jonowej. Zaobserwowano, że adsorpcja barwnika Direct Orange 26 na wszystkich trzech adsorbentach była silnie zależna od pH roztworu, natomiast siła jonowa roztworu nie wpływała na efektywność adsorpcji. Kinetyka adsorpcji była zgodna z modelem reakcji pseudo-drugiego rzędu. Etapem decydującym o szybkości adsorpcji jest dyfuzja barwnika w warstwie przypowierzchniowej. Proces adsorpcji równowagowej barwnika Direct Orange 26 na wszystkich badanych adsorbentach najlepiej opisuje izoterma Langmuira. Maksymalne zdolności adsorpcyjne dla torfu, węgla brunatnego i węgla kamiennego wynosiły odpowiednio 17,7, 15,1 i 13,8 mg/g. Wyniki wskazują, że torf, węgiel brunatny i węgiel kamienny mogą być rozważane jako alternatywne adsorbenty do usuwania barwników azowych z roztworów wodnych.

2

Enhanced adsorption of Direct Orange 26 dye in aqueous solutions by modified halloysite

Kuśmierek Krzysztof, Świątkowski Andrzej, Wierzbicka Ewa, Legocka Izabella

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 4

693--701

EN

The usefulness of untreated (H-NM) as well as modified by sodium benzoate (H-SB) and sulfuric acid (H-SA1 and H-SA2) halloysites as low-cost adsorbent for the removal of Direct Orange 26 azo dye from aqueous solutions was investigated. The kinetic data were evaluated in terms of the pseudo-first order and pseudo-second order kinetic models, while the equilibrium adsorption data were analyzed by the Freundlich and Langmuir isotherm equations. The data follows the pseudo-second order kinetic and Langmuir adsorption models. The DO26 adsorption capacities were 64.93, 74.07, 303.0, and 384.4 μmol/g for the H-NM, H-SB, H-SA1, and H-SA2, respectively. Adsorption of the dye was strongly pH dependent; no effect of ionic strength was observed. The study revealed that halloysites, especially acid-activated halloysites, could be used as an effective and low-cost adsorbents.

3

Waste Plant Material as a Potential Adsorbent of a Selected Azo Dye

Tomczak E., Tosik P.

Chemical and Process Engineering

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2017

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Vol. 38, nr 2

283--294

EN

This paper discusses the adsorption of Direct Orange 26 azo dye on sunflower husk - an agricultural waste product. During the study, sorption kinetics and equilibrium as well as sorption capacity of the husk were investigated. The adsorption kinetics was analyzed using pseudo-first and pseudo-second order equations, which indicated a chemical sorption mechanism. The sorption equilibrium was approximated with the two-parameter Freundlich and Langmuir equations and the three-parameter Redlich-Peterson equation. The main experiments were carried out in a laboratory adsorption column under different process conditions. Experimental data were interpreted with the Thomas model, based on the volumetric flow rate, initial composition of the feed solution and mass of the adsorbent. The results of modeling the adsorption equilibrium, adsorption kinetics and adsorption dynamics were evaluated statistically.