scholarly journals Use of aminated hulls of sunflower seeds for the removal of anionic dyes from aqueous solutions

2019 ◽  
Vol 17 (3) ◽  
pp. 1211-1224 ◽  
Author(s):  
T. Jóźwiak ◽  
U. Filipkowska ◽  
S. Brym ◽  
L. Kopeć

Abstract In this study, we analyzed the effectiveness of sorption of dyes popular in the textile industry (Reactive Black 5, Reactive Yellow 84, Acid Yellow 23, and Acid Red 18) on aminated and non-aminated seed hulls of common sunflower (Helianthus annuus L.). The scope of the study included: determination of the effect of pH on dye sorption effectiveness, sorption kinetics analyses (sorption equilibrium time, pseudo-first-order/pseudo-second-order model, intramolecular diffusion model), and determination of the maximum sorption capacity against dyes (Langmuir/Freundlich isotherm). The sorbent was subjected to the FTIR analysis. The sorption capacity of the aminated sunflower seed hulls against reactive dyes RB5 and RY84 accounted for 51.02 mg/g and 63.27 mg/g, respectively, and was higher by 1665% (17.6 times higher) and 1425% (15.3 times higher) compared to that of non-modified hulls. In the case of acidic dyes, Acid Yellow 23 and Acid Red 18, the sorption capacity of the aminated sunflower seed hulls reached 44.78 mg/g and 42.19 mg/g, respectively, and was higher by 1881% (19.8 times higher) and 2284% (23.8 times higher), respectively, compared to the non-modified hulls.

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5646
Author(s):  
Joanna Kluczka ◽  
Gabriela Dudek ◽  
Wojciech Pudło ◽  
Alicja Kazek-Kęsik ◽  
Roman Turczyn

An excess concentration of boron in irrigation and drinking water can negatively affect the yield of plants and the human nervous system, respectively. To meet the recommended levels, hybrid biosorbent hydrogel beads based on chitosan and manganese (II-IV) were employed for the removal of boron from aqueous media. The results showed that the biosorbent effectively removed boric acid from the aqueous medium at neutral pH over a sorption time of 2 h and the liquid/hydrogel ratio of 20 mL/g, achieving a maximum sorption capacity near 190 mg/g. The modeling of the sorption equilibrium data indicated that the Freundlich isotherm equation gave the best fit out of the isotherm models examined. A pseudo-second-order model was found to best describe the sorption kinetics. The favorable attachment of manganese to the chitosan structure enabled the sorption of boron and was confirmed by FTIR, RS, XRD, SEM and ICP-OES methods. Boron desorption from the spent biosorbent was successfully achieved in three cycles using a NaOH solution. In general, the results of this research indicate that this method is one of the possibilities for improving water quality and may contribute to reducing pollution of the aquatic environment.


Author(s):  
Urszula Filipkowska ◽  
Tomasz Jóźwiak ◽  
Paula Bugajska ◽  
Małgorzata Kuczajowska-Zadrożna

This article presents the influence of chitin amination on the effectiveness of RB5 and RY84 dye sorption. For chitin and chitin modified by amination, the optimal pH of sorption and the maximum sorption capacity were determined in relation to two reactive dyes: Reactive Black 5 (RB5) and Reactive Yellow 84 (RY84), differing in the active group and molecular weight. Three sorption models were used to describe the experimental data: Langmuir, Langmuir 2 and Freundlich. The highest sorption capacity was obtained for aminated chitin for both tested dyes: 386.53 mg/g for RB5 and 261.56 mg/g for RY84. In the case of sorption on unmodified chitin, the sorption capacities were lower: up to 235.65 mg/g.d.m. for RB5 and 208.88 mg/g.d.m. for RY84. The modification of chitin by amination has a beneficial effect on the amount of dye adsorbed in the process. The adsorptive capacity increased by 1.6-times in the case of RB5 and 1.25-times in case of RY84.


2013 ◽  
Vol 33 (8) ◽  
pp. 735-747 ◽  
Author(s):  
Urszula Filipkowska ◽  
Tomasz Jóźwiak

Abstract The study analyzed the sorption effectiveness of reactive dyes, Reactive Black 5 (RB5) and Reactive Yellow 84 (RY84), onto non-cross-linked chitosan beads (CHs) and onto CHs cross-linked with glutaraldehyde (ALD) i.e., ALD-CHs and epichlorohydrin (ECH) i.e., ECH-CHs. The study enabled determination of the optimal ratio of the cross-linking agent to chitosan and the optimal pH of the sorption process (from the range of 1:10–10:1, to 2–12, respectively). The time needed to reach the equilibrium concentration reached 504 h. Satisfactory effects of RB5 and RY84 sorption were achieved after 24 h sorption. Data were described with the heterogenous Langmuir’s model (double Langmuir’s equation). For RB5 dye, the most effective sorbent turned out to be CHs – the maximum sorption capacity reached 2025.11 (mg/g). For the other sorbents, ALD-CHs and ECH-CHs, the capacity accounted for 1797.0 mg/g and 1816.1 mg/g, respectively. In the case of RY84 dye, the most effective sorbent appeared to be ECH-CHs – 2234.3 mg/g. For CHs and ALD-CHs, the highest sorption capacities against RY84 reached 1774.2 and 2000.1 mg/g, respectively.


2019 ◽  
Vol 73 (4) ◽  
pp. 223-237
Author(s):  
Danijela Bojic ◽  
Milos Kostic ◽  
Miljana Radovic-Vucic ◽  
Nena Velinov ◽  
Slobodan Najdanovic ◽  
...  

Lagenaria vulgaris activated carbon (LVAC) was synthesized from Lagenaria vulgaris biomass by treatment with diluted H2SO4 followed by thermo-chemical carbonization and overheated steam activation process and used for removal of the herbicide 2,4-dichlo-rophenoxyacetic acid (2,4-D). Fourier transform infrared spectroscopy (FTIR) indicated that 2,4-D is adsorbed in micropores of the very porous LVAC (665 m2 g-1). LVAC showed high sorption capacity as compared to many previously used sorbents at optimal conditions: the stirring rate of 300 rpm, the sorbent dose of 1.0 g dm-3 and pH from 2 to 7. The experimental maximum sorption capacity of LVAC was 333.3 mg g-1. The pseudo-second-order model and Chrastil model described the 2,4-D sorption kinetics by LVAC. Thermodynamic studies have indicated that the sorption process was endothermic, spontaneous and physical in nature. LVAC was shown to be an ultrahighly efficient sorbent for removal of 2,4-D from groundwater, which could be also recycled and reused.


Author(s):  
A. Safonov ◽  
N. Andriushchenko ◽  
N. Popova ◽  
K. Boldyrev

Проведен анализ сорбционных характеристик природных материалов (вермикулит, керамзит, перлит, цеолит Трейд ) при очистке кадмий- и хромсодержащих сточных вод с высокой нагрузкой по ХПК. Установлено, что цеолит обладает максимальными сорбционными характеристиками для Cd и Cr и наименьшим биологическим обрастанием. При использовании вермикулита и керамзита или смесей на их основе можно ожидать увеличения сорбционной емкости для Cd и Сr при микробном обрастании, неизбежно происходящем в условиях контакта с водами, загрязненными органическими соединениями и биогенами. При этом биообрастание может повысить иммобилизационную способность материалов для редоксзависимых металлов за счет ферментативных ресурсов бактериальных клеток, использующих их в качестве акцепторов электронов. Эффект микробного обрастания разнонаправленно изменял параметры материалов: для Cr в большинстве случаев уменьшение и для Cd значительное увеличение. При этом дополнительным эффектом иммобилизации Cr является его биологическое восстановление биопленками. Варьируя состав сорбционного материала, можно подбирать смеси, оптимально подходящие для очистки вод инфильтратов с полигонов твердых бытовых отходов с высокой нагрузкой по ХПК и биогенным элементам как при использовании in situ, так и в системах на поверхности.The analysis of the sorption characteristics of natural materials (vermiculite, expanded clay, perlite, Trade zeolite) during the purification of cadmium and chromium-containing leachate with a high COD load was carried out. It was determined that zeolite had the maximum sorption capacity for Cd and Cr and the lowest biological fouling. When using vermiculite and expanded clay or mixtures on their basis, one can expect an increase in the sorption capacity for Cd and Cr during microbial fouling that inevitably occurs during contacting with water polluted with organic compounds and nutrients. In this case biofouling can increase the immobilization properties of materials for redox-dependent metals due to the enzymatic resources of bacterial cells that use them as electron acceptors. The effect of microbial fouling changed the parameters of materials in different directions: for Cr, in most cases, downward, and for Cd, significantly upward. Moreover, chromium biological recovery by biofilms is an additional effect of immobilization. Varying the composition of the sorption material provides for selecting mixtures that are optimally suitable for the purification of leachates from solid waste landfills with high COD and nutrients load, both when used in situ and in surface systems.


2021 ◽  
Vol 13 (3) ◽  
pp. 1502
Author(s):  
Maria Xanthopoulou ◽  
Dimitrios Giliopoulos ◽  
Nikolaos Tzollas ◽  
Konstantinos S. Triantafyllidis ◽  
Margaritis Kostoglou ◽  
...  

In water and wastewater, phosphate anions are considered critical contaminants because they cause algae blooms and eutrophication. The present work aims at studying the removal of phosphate anions from aqueous solutions using silica particles functionalized with polyethylenimine. The parameters affecting the adsorption process such as pH, initial concentration, adsorbent dose, and the presence of competitive anions, such as carbonate, nitrate, sulfate and chromate ions, were studied. Equilibrium studies were carried out to determine their sorption capacity and the rate of phosphate ions uptake. The adsorption isotherm data fitted well with the Langmuir and Sips model. The maximum sorption capacity was 41.1 mg/g at pH 5, which decreased slightly at pH 7. The efficiency of phosphate removal adsorption increased at lower pH values and by increasing the adsorbent dose. The maximum phosphate removal was 80% for pH 5 and decreased to 75% for pH 6, to 73% for pH 7 and to 70% for pH 8, for initial phosphate concentration at about 1 mg/L and for a dose of adsorbent 100 mg/L. The removal rate was increased with the increase of the adsorbent dose. For example, for initial phosphate concentration of 4 mg/L the removal rate increased from 40% to 80% by increasing the dose from 0.1 to 2.0 g/L at pH 7. The competitive anions adversely affected phosphate removal. Though they were also found to be removed to a certain extent. Their co-removal provided an adsorbent which might be very useful for treating waters with low-level multiple contaminant occurrence in natural or engineered aquatic systems.


Soil Research ◽  
2007 ◽  
Vol 45 (8) ◽  
pp. 618 ◽  
Author(s):  
Wanting Ling ◽  
Qing Shen ◽  
Yanzheng Gao ◽  
Xiaohong Gu ◽  
Zhipeng Yang

A decrease in release and availability of heavy metals in soil has been of worldwide interest in recent years. Bentonite is a type of expandable montmorillonite clay, and has strong sorption for heavy metals. In this work, the control of amended bentonite on the release of copper (Cu2+) from spiked soils was investigated using a batch equilibrium technique. Sorption of Cu by bentonite was pH-dependent, and could be well described using the Langmiur model. Maximum sorption capacity of the bentonite used in this study was 5.4 mg/g, which was much greater than soils reported in the literature. The extent of Cu2+ release from spiked soils was correlated with slurry concentrations, pH, and soil ageing process. In all cases, the amendment of bentonite was observed to effectively decrease the release of Cu2+ from soils. The apparent aqueous concentrations of Cu2+ released from soils devoid of bentonite treatment were 113–1160% higher than those from the soils amended with bentonite. Moreover, the magnitude of Cu2+ release decreased with increasing amount of bentonite added to soils. The bentonite added was more effective in retaining Cu2+ in sorbents for aged contaminated soils. Such enhanced retention resulting from the presence of bentonite was observed within a wide pH range from 2.5 to 7.0. Bentonite, as one of the most abundant minerals in soils, is regarded to improve the soil overall quality. The results obtained from this work provide useful information on utilisation of bentonite to control the release of heavy metals from contaminated soils.


RSC Advances ◽  
2014 ◽  
Vol 4 (76) ◽  
pp. 40580-40587 ◽  
Author(s):  
Prasanta Kumar Raul ◽  
Samarpita Senapati ◽  
Ashish K. Sahoo ◽  
Iohborlang M. Umlong ◽  
Rashmi R. Devi ◽  
...  

CuO nanorods can remove Pb(ii) from aqueous solution with a maximum sorption capacity of 3.31 mg g−1at 298 K.


2015 ◽  
Vol 16 (1) ◽  
pp. 115-127 ◽  
Author(s):  
P. Dhanasekaran ◽  
P. M. Satya Sai ◽  
C. Anand Babu ◽  
R. Krishna Prabhu ◽  
K. K. Rajan

Arsenic is a toxic element found naturally in groundwater. Due to its carcinogenicity, risk for heart diseases and diabetes, arsenic needs to be removed from groundwater for potable application. ‘Anjili’ tree sawdust was chemically modified with ferric hydroxide and activated alumina (SFAA) and used as an adsorbent for the removal of arsenic from groundwater. The adsorbent was characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) to study the pore structure and surface functional groups. Effect of contact time, initial concentration, pH, particle size and temperature was studied. Arsenic adsorbed by SFAA followed Freundlich adsorption isotherm. Maximum sorption of arsenic by SFAA adsorbent occurred at pH 6.5. Arsenic sorption kinetics followed a pseudo-second-order model. The maximum sorption capacity at 303 K was found to be 54.32 mg/g for As(III) and 77.60 mg/g for As(V). Interference of other ions on the adsorption was in the order of PO43− > SO42− > HCO3− > NO3−.


RSC Advances ◽  
2015 ◽  
Vol 5 (70) ◽  
pp. 56658-56665 ◽  
Author(s):  
X. T. Chen ◽  
L. F. He ◽  
R. Z. Liu ◽  
C. Zhang ◽  
B. Liu ◽  
...  

A bi-functionalized magnetic iron oxide composite has been employed for uranium(vi) sorption from alkaline media. The maximum sorption capacity was observed at pH 9.0 with a capacity of 70.7 mg g−1atcU(vi)initial= 21.7 mg L−1.


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