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1

Removal of textile dyes from water using cellulose aerogel

Liugė Monika, Paliulis Dainius, Kumpienė Jūratė, Paulauskienė Tatjana

Ecological Chemistry and Engineering. S

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2024

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Vol. 31, nr 1

49--62

EN

In this study, removal of textile dyes from artificially contaminated water was investigated using sorbent synthesised from cardboard waste. Aerogel - lightweight adsorbent - a material with a low density and large surface area. Aerogels obtained from cellulose, chitosan, lignin or pectin have good adsorption properties for removing organic pollutants from wastewater. The aim of this study was to determine the adsorption efficiency of naphthol green B, congo red, methylene blue and rhodamine B from artificially contaminated water using sorbent synthesised from cardboard waste. The mass of the cellulose aerogel (5 mas. %) adsorbents, that were used in the experiments varied from 1.6 g to 2.74 g. The optimal adsorption conditions were determined as pH = 6.0, concentration of dyes - 10 mg L–1 and 18.0 °C -19.0 °C temperature. Under the optimal conditions, the maximum removal efficiency of naphthol green B using aerogel was 16.45 %; congo red - 98.44 %; methylene blue 79.28 %; and rhodamine B - 52.44 %.

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Comparison of bomaplex blue CR-L removal by adsorption using raw and activated pumpkin seed shells

İrdemez Şahset, Özyay Gizem, Ekmekyapar Torun Fatma, Kul Sinan, Bingül Züleyha

Ecological Chemistry and Engineering. S

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2022

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Vol. 29, nr 2

199--216

EN

In this study, removal of colour from wastewaters prepared synthetically using Bomaplex Blue CR-L was investigated using raw and activated pumpkin seed shells by adsorption in a batch system. The effects of stirring speed, adsorbent concentration, dye concentration, temperature and pH on colour removal were investigated, and adsorption capacities of raw and activated pumpkin seed shells were determined. In addition, adsorption kinetics, isotherm coefficients, activation energies and thermodynamic parameters were calculated. The optimal adsorption conditions were determined as pH = 2, stirring speed of 200 rpm, adsorbent concentration of 10 g L–1 and 30 °C. Under the optimal conditions, the maximum removal efficiency of Bomaplex Blue CR-L using raw pumpkin seed shells was 73.01 %. This value rose to 79.71 % after activation processing was applied. Experimental adsorption data show that the adsorption is more suited to the Langmuir adsorption model and works in accordance with the pseudo-first-order kinetics model. As a result of thermodynamic research, ΔH° and ΔS° were 31.515 kJ mol–1 and 109.952 kJ mol–1 K–1 for the raw adsorbent, respectively. For the activated adsorbent, ΔH° and ΔS° were 43.118 kJ mol–1 and 152.237 kJ mol–1 K–1, respectively. The activation energy of adsorption was calculated as 10.918 kJ mol–1 for the raw adsorbent and 9.882 kJ mol–1 for the activated adsorbent.

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Utilization of Khamir (Saccharomyces cerevisiae) as Adsorbent of Remazol Red RB Textile Dyes

Sukarta I Nyoman, Ayuni Ni Putu Sri, Sastrawidana I Dewa Ketut

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 1

117--123

EN

Adsorption is considered the most efficient and simple method that requires low costs. In this study, firstly, yeast (Saccharomyces cerevisiae) was used to adsorption the Remazol Red RB dyes to analyze the efficiency of yeast as an adsorbent of textile dyes as well as determine the particle size, pH, and optimum contact time. Testing of the particle size parameters was done with variations of 100, 170, and 200 mesh size. The optimum conditio was obtained in the particle size variation amounting to 200 mesh size with efficiency %E of 56.49%. Subsequent testing was conducted with variations in pH (5.6, 7, 8, and 9). The optimum condition was obtained at pH 6 with efficiency %E of 60.35%. The dyestuffs were conquerable with variations in time of 1, 2, 3, 4, and 5 hours, the largest %E gained was 90.01% throughout 4 hours. Secondly, the research also aimed at identifying the isotherm adsorption pattern. Adsorption in Remazol Red RB dyes fulfilled the isotherm pattern of Langmuir with a correlation coefficient R2 of 0.9521 and the maximum capacity of the yeast adsorption of 0.07 mg/g. Further research is expected to expand the analysis variation and the type of textile dyes used which can be applied to the actual textile dyes waste.

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Zastosowanie kompostu jako taniego sorbentu do usuwania barwników z roztworów wodnych

Jóźwiak T., Filipkowska U., Rodziewicz J., Mielcarek A., Owczarkowska D.

Rocznik Ochrona Środowiska

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2013

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Tom 15, cz. 3

2398--2411

EN

This study was aimed at determining the feasibility of using compost as an unconventional sorbent for dyes removal from aqueous solutions. Compost applied in the study was a product of sewage sludge composting with plant residues (birch wood chips and rapeseed straw). Experiments were conducted for two anionic reactive dyes: Reactive Yellow 84 [RY84] (1701 g/mol – λmax = 357.5 nm) and Reactive Black 5 [RB5] (991 g/mol – λmax = 600.0 nm), and for two cationic dyes: Basic Green 4 [BG4] (365 g/mol – λmax = 618.0 nm) and Basic Violet 10 [BV10] (479 g/mol – λmax = 547.5 nm). The scope of the study included: determination of the optimal pH value of dyes adsorption onto compost, determination of equilibrium time of dyes sorption onto compost, determination of the maximum sorption capacity of the analyzed dyes on compost. During each experiment, sorbent concentration in the solution was at 5 g d.m./dm3. The concentration of dye remaining in the solution was determined with the spectrophotometric method on a UV-VIS SP 2000 spectrophotometer. Analyses were conducted at a room temperature – T = 22°C. The pH value of solutions was adjusted with aqueous solutions of HCl and NaOH. Sorption of the anionic reactive dyes RY84 and RB5 was the most effective at pH = 3. The optimal pH value of cationic dyes sorption was established at pH = 5. At a high pH value (pH = 9), the sorption of each type of dye was impaired due to partial solubilization of the compost sorbent. The equilibrium time of dyes sorption on compost accounted for 180 min in the case of RY84, RB5 and BG4, and for 240 min in the case of BV10 – 240 min. Analyses of the maximum sorption capacity of the selected dyes on compost were carried out already after establishing the optimal pH value of the sorption process for each dye. Results obtained were described with the use of two sorption models: a heterogenous Langmuir 2 model (double Langmuir equation), and a heterogenousFreundlich model. The Langmuir 2 model showed the best fit to experimental data (R2> 0.99). Due to the presence of functional groups -COOH and -OH, compost is negatively charged in aqueous solutions owing to which it prefers compounds with a positive charge (cationic dyes) during sorption. Electrostatic repulsion significantly impairs the adsorption of anionic dyes. The maximum sorption capacity of compost in the case of RY84 and RB5 reached 2.15 mg/g d.m. and 4.79 mg/g d.m., whereas in the case of BG4 and BV10 – 26.41 mg/g d.m. and 27.20 mg/g d.m., respectively. Results of the maximum sorption capacity of dyes on compost were referred to results obtained with other unconventional and cheap sorbents.

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Photosensitized decomposition of textile dyes on TiO2-Tytanpol A11 and TiO2-Degussa P25

Zielińska B., Morawski A. W., Kaleńczuk R. J.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 3

150-152

EN

The photoassisted decomposition of five organic dyes (Reactive Red 198 (RR198), Reactive Black 5 (RB5), Acid Black 1 (AB1), Direct Green 99 (DG99) and Acid Blue 7 (AB7)) has been investigated in aqueous solution in the presence of two kinds of TiO2 photocatalysts: TiO2-Tytanpol A11 (,,Police" Chemical Factory, Poland) and TiO2-Degussa P25 (,,Degussa" Germany) and under the illumination by the Vis light. The results suggest that the value of the adsorption of the dyes on the photocatalyst surface is the controlling step of the photosensitized degradation of dyes. The A11 photocatalyst demonstrates higher activity than P25. This effect is diffrent from the one obtained under the UV illumination, where P25 shows a much higher activity. Additionally, it was investigated that for both phototocatalysts used the degree of dyes decomposition decreased with the increasing of the maximum absorption of the dyes.