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Journal of Environmental Management Jul 2023The current paper refers to the study of a new approach to optimizing the adsorptive properties of geopolymers by varying the aluminosilicate precursors from kaolin (K),...
The current paper refers to the study of a new approach to optimizing the adsorptive properties of geopolymers by varying the aluminosilicate precursors from kaolin (K), metakaolin (MK), and coal fly ash (CFA) as internal synthesis factors. The simplex-augmented-centroid mixture design was applied to identify the optimal formulation from the three aluminosilicate precursors to develop a geopolymer (GP) with a distinctive structure that positively affects its dye adsorption efficiency. The variously formulated GP samples were tested for the removal of both methylene blue (MB-dye) and crystal violet dye (CV-dye) from an aqueous solution. The mathematical-statistical analysis of the experimental readings suggested that the generated special cubic models were significant, and thus the chosen approach was adequate for determining the optimum blending proportion. The optimization tools indicated that the optimal mixture from the three aluminosilicate precursors for developing a GP with high adsorption efficiency was 58% MK, 42% K, and 0% CFA. The optimized geopolymer (GP) was synthesized and then analyzed using a variety of physicochemical techniques, which revealed the presence of an amorphous N-A-S-H gel-rich porous structure as an influencing property on the geopolymer's organic dye adsorption efficiency. The dependence of the adsorption mechanism of both MB-dye and CV-dye by GP on the adsorbent dosage, contact time, initial dye concentration, temperature, and solution pH was evaluated. The isothermic and kinetic experimental readings for MB and CV-dyes adsorption by GP were well fitted to the pseudo-second-order and Freundlich models, with an exothermic, favorable, and spontaneous adsorption reaction thermodynamically. The experimental studies in the lab scale on GP produce comparable results. From these results, it has been concluded that the accuracy and feasibility of the mixture design simulation succeeded in optimizing and developing a geopolymeric sorbent material with great potential as an excellent economical agent for removing cationic dyes from aqueous media. This point represents an added value compared to traditional non-optimized geopolymer absorbents. Besides, this geopolymer material represents a significant application possibility for water treatment and remediation of hazardous dye pollutants.
Topics: Water Pollutants, Chemical; Coal Ash; Aluminum Silicates; Coloring Agents; Adsorption; Kinetics; Hydrogen-Ion Concentration
PubMed: 37015145
DOI: 10.1016/j.jenvman.2023.117853 -
Chemosphere Jul 2024Textile and cosmetic industries generate large amounts of dye effluents requiring treatment before discharge. This wastewater contains high levels of reactive dyes, low... (Review)
Review
Textile and cosmetic industries generate large amounts of dye effluents requiring treatment before discharge. This wastewater contains high levels of reactive dyes, low to none-biodegradable materials and chemical residues. Technically, dye wastewater is characterised by high chemical and biological oxygen demand. Biological, physical and pressure-driven membrane processes have been extensively used in textile wastewater treatment plants. However, these technologies are characterised by process complexity and are often costly. Also, process efficiency is not achieved in cost-effective biochemical and physical treatment processes. Membrane distillation (MD) emerged as a promising technology harnessing challenges faced by pressure-driven membrane processes. To ensure high cost-effectiveness, the MD can be operated by solar energy or low-grade waste heat. Herein, the MD purification of dye wastewater is comprehensively and yet concisely discussed. This involved research advancement in MD processes towards removal of dyes from industrial effluents. Also, challenges faced by this process with a specific focus on fouling are reviewed. Current literature mainly tested MD setups in the laboratory scale suggesting a deep need of further optimization of membrane and module designs in near future, especially for textile wastewater treatment. There is a need to deliver customized high-porosity hydrophobic membrane design with the appropriate thickness and module configuration to reduce concentration and temperature polarization (CP and TP). Also, energy loss should be minimized while increasing dye rejection and permeate flux. Although laboratory experiments remain pivotal in optimizing the MD process for treating dye wastewater, the nature of their time intensity poses a challenge. Given the multitude of parameters involved in MD process optimization, artificial intelligence (AI) methodologies present a promising avenue for assistance. Thus, AI-driven algorithms have the potential to enhance overall process efficiency, cutting down on time, fine-tuning parameters, and driving cost reductions. However, achieving an optimal balance between efficiency enhancements and financial outlays is a complex process. Finally, this paper suggests a research direction for the development of effective synthetic and natural dye removal from industrially discharged wastewater.
Topics: Wastewater; Distillation; Coloring Agents; Waste Disposal, Fluid; Membranes, Artificial; Water Pollutants, Chemical; Textile Industry; Water Purification; Industrial Waste
PubMed: 38759802
DOI: 10.1016/j.chemosphere.2024.142347 -
Environmental Science and Pollution... Sep 2023The uncontrolled dumping of synthetic dyes into water sources has posed severe hazards to the ecosystem. For decades, several materials with low cost and high efficiency...
The uncontrolled dumping of synthetic dyes into water sources has posed severe hazards to the ecosystem. For decades, several materials with low cost and high efficiency have been investigated for dye degradation. Photocatalytic degradation is regarded as a successful strategy since it utilizes sunlight to transform harmful pollutants into nontoxic compounds without using oxidative agents. The photocatalytic potentials of CeO/g-CN (CG) were investigated in this work using a simplistic ultrasonication process. Here, the amount of CeO was fixed, and g-CN was varied in the ratio (1:x, where x = 1, 2, and 3) and abbreviated as CG1, CG2, and CG3. Characterization techniques such as Fourier transforms-infrared spectroscopy, thermal gravimetric analysis (TGA), powdered X-ray diffraction, ultraviolet-visible spectroscopy, etc. were used to characterize structural analysis, optical properties, particle size, and chemical bonds of the prepared nanocomposites. The photocatalytic results showed that CG2 effectively degraded rose bengal (RB) and crystal violet (CV) dyes when exposed to visible light irradiation as compared to pure GCN and CeO. The antibacterial activity analysis further supported the potential application of prepared photocatalyst as a disinfectant agent against both gram-positive (Staphylococcus aureus and Bacillus cereus) and gram-negative (Salmonella abony and Escherichia coli) pathogenic strains of bacteria.
Topics: Coloring Agents; Ecosystem; Catalysis; Anti-Bacterial Agents; Nanocomposites
PubMed: 36318413
DOI: 10.1007/s11356-022-23815-x -
Bioorganic Chemistry Nov 2023The study investigated the structure-activity relationship of newly synthesized dye-linker-macrocycle (DLM) conjugates and the effect of each component on various...
The study investigated the structure-activity relationship of newly synthesized dye-linker-macrocycle (DLM) conjugates and the effect of each component on various biological properties, including cytotoxicity, cellular uptake, intracellular localization, interaction with DNA and photodynamic effects. The conjugates were synthesized by combining 1,8-naphthalimide and thioxanthone dyes with 1,4,7,10-tetraazacyclododecane (cyclen) and 1-aza-12-crown-4 (1A12C4) using alkyl linkers of different lengths. The results revealed significant differences in biological activity among the various series of conjugates. Particularly, 1A12C4 conjugates exhibited notably higher cytotoxicity compared to cyclen conjugates. Conjugation with 1A12C4 proved to be an effective strategy for increasing cellular uptake and cytotoxicity of small-molecule conjugates. In addition, the results highlighted the critical role of linker length in modulating the biological activity of DLM conjugates. It became clear that the choice of each component (dye, macrocycle and linker) could significantly alter the biological activity of the conjugates.
Topics: Cyclams; Biological Transport; Antineoplastic Agents; Coloring Agents
PubMed: 37659149
DOI: 10.1016/j.bioorg.2023.106782 -
Archives of Microbiology May 2024The employment of versatile bacterial strains for the efficient degradation of carcinogenic textile dyes is a sustainable technology of bioremediation for a neat, clean,...
The employment of versatile bacterial strains for the efficient degradation of carcinogenic textile dyes is a sustainable technology of bioremediation for a neat, clean, and evergreen globe. The present study has explored the eco-friendly degradation of complex Reactive Green 12 azo dye to its non-toxic metabolites for safe disposal in an open environment. The bacterial degradation was performed with the variable concentrations (50, 100, 200, 400, and 500 mg/L) of Reactive Green 12 dye. The degradation and toxicity of the dye were validated by high-performance liquid chromatography, Fourier infrared spectroscopy analysis, and phytotoxicity and genotoxicity assay, respectively. The highest 97.8% decolorization was achieved within 12 h. Alternations in the peaks and retentions, thus, along with modifications in the functional groups and chemical bonds, confirmed the degradation of Reactive Green 12. The disappearance of a major peak at 1450 cm corresponding to the -N=N- azo link validated the breaking of azo bonds and degradation of the parent dye. The 100% germination of Triticum aestivum seed and healthy growth of plants verified the lost toxicity of degraded dye. Moreover, the chromosomal aberration of Allium cepa root cell treatment also validated the removal of toxicity through bacterial degradation. Thereafter, for efficient degradation of textile dye, the bacterium is recommended for adaptation to the sustainable degradation of dye and wastewater for further application of degraded metabolites in crop irrigation for sustainable agriculture.
Topics: Biodegradation, Environmental; Coloring Agents; Textile Industry; Triticum; Onions; Azo Compounds; Textiles; Bacteria; Mutagenicity Tests
PubMed: 38753198
DOI: 10.1007/s00203-024-03994-6 -
International Journal of Molecular... Jul 2023Oxidases and peroxidases have found application in the field of chlorine-free organic dye degradation in the paper, toothpaste, and detergent industries. Nevertheless,...
Oxidases and peroxidases have found application in the field of chlorine-free organic dye degradation in the paper, toothpaste, and detergent industries. Nevertheless, their widespread use is somehow hindered because of their cost, availability, and batch-to-batch reproducibility. Here, we report the catalytic proficiency of a miniaturized synthetic peroxidase, Fe-Mimochrome VI*a, in the decolorization of four organic dyes, as representatives of either the heterocyclic or triarylmethane class of dyes. Fe-Mimochrome VI*a performed over 130 turnovers in less than five minutes in an aqueous buffer at a neutral pH under mild conditions.
Topics: Peroxidase; Coloring Agents; Reproducibility of Results; Peroxidases; Catalysis
PubMed: 37446248
DOI: 10.3390/ijms241311070 -
Soft Matter Aug 2023The intriguing role of the intracellular crowded environment in regulating protein aggregation remains elusive. The convolution of several factors such as the protein...
The intriguing role of the intracellular crowded environment in regulating protein aggregation remains elusive. The convolution of several factors such as the protein sequence-dependence, crowder's shape and size and diverse intermolecular interactions makes it complex to identify systematic trends. One of the ways to simplify the problem is to study a synthetic model for self-assembling proteins. In this study, we examine the aggregation behaviour of the cationic pseudoisocyanine chloride (PIC) dyestuff which is known to self-assemble and form fibril-like J-aggregates in aqueous solutions, similar to those formed by amyloid-forming proteins. Prior experimental studies have shown that polyethylene glycol impedes and Ficoll-400 promotes the self-assembly of PIC dyes. To achieve molecular insights, we examine the effect of crowding by ethylene glycol on the solvation thermodynamics of oligomerization of dyes into H-type and J-type oligomers using extensive molecular dynamics simulations. The binding free energy calculations show that the formation of J-oligomers is more favourable than that of H-oligomers in water. The stability of H- and J- tetramers and pentamers decreases in crowded solutions. The formation of oligomers is supported by the favourable change in dye-solvent interaction energy in both pure water and aqueous ethylene glycol solution although it is opposed by the reduced dye-solvent entropy. Ethylene glycol, as a molecular crowder, disfavours the H- as well as J-oligomerization preferential binding to the dye oligomers. An unfavourable change in dye-crowder and dye-dye interaction energy on dye association makes the H-oligomer formation less favourable in crowded solution than in pure water solution. In the case of J-oligomers, however, the unfavourable change in dye-crowder interaction energy primarily contributes to making total dye-solvent energy unfavourable. The results are supported by isothermal titration calorimetry measurements where the binding of ethylene glycol to PIC molecules is found to be endothermic. The results provide an emerging view that a crowded environment can disfavour self-assembly of PIC dyes by interactions with the oligomeric states. The findings have implications in understanding the role of a crowded environment in shaping the free energy landscapes of proteins.
Topics: Ethylene Glycol; Coloring Agents; Water; Solvents
PubMed: 37580997
DOI: 10.1039/d3sm00564j -
International Journal of Biological... Dec 2023Renewable energy, such as solar energy, is infinite, readily available, and has extensive applications. Dye-sensitized solar cells (DSSCs) have been well developed;...
Renewable energy, such as solar energy, is infinite, readily available, and has extensive applications. Dye-sensitized solar cells (DSSCs) have been well developed; thus, they can be developed with low production costs, high efficiency, and facile manufacturing techniques. This study proposes a novel chitosan biopolymer-based perylene dye; the dye is modified by chitosan with perylene-3,4,9,10-tetracarboxylic anhydride using a one-pot acylation of nitrogen nucleophiles for DSSCs. The chitosan biopolymer-based perylene dyes were characterized using attenuated total reflection infrared spectroscopy, solid-state C CP-TOSS nuclear magnetic resonance spectroscopy, X-ray powder diffraction analysis, thermogravimetric analysis, X-ray photoelectron spectrometry, and high-resolution field-emission scanning electron microscopy. The ultraviolet-visible and fluorescence spectroscopy of chitosan biopolymer-based perylene dye exhibited a red-shift compared with perylene-3,4,9,10-tetracarboxylic anhydride and chitosan. The DSSC properties of chitosan biopolymer-based perylene dye were investigated, and it exhibited a 2.022 % power-conversion efficiency. Thus, this promising chitosan biopolymer-based perylene dye may have potential applications in solar-cell technology.
Topics: Coloring Agents; Chitosan; Perylene; Biopolymers; Anhydrides
PubMed: 37722641
DOI: 10.1016/j.ijbiomac.2023.126964 -
Cellular Signalling Sep 2023Genetically encoded Ca indicators have become widely used in cell signalling studies as they offer advantages over cell-loaded dye indicators in enabling specific...
Genetically encoded Ca indicators have become widely used in cell signalling studies as they offer advantages over cell-loaded dye indicators in enabling specific cellular or subcellular targeting. Comparing responses from dye and protein-based indicators may provide information about indicator properties and cell physiology, but side-by-side recordings in cells are scarce. In this study, we compared cytoplasmic Ca concentration ([Ca]) changes in insulin-secreting β-cells recorded with commonly used dyes and indicators based on circularly permuted fluorescent proteins. Total internal reflection fluorescence (TIRF) imaging of K depolarization-triggered submembrane [Ca] increases showed that the dyes Fluo-4 and Fluo-5F mainly reported stable [Ca] elevations, whereas the proteins R-GECO1 and GCaMP5G more often reported distinct [Ca] spikes from an elevated level. [Ca] spiking occurred also in glucose-stimulated cells. The spikes reflected Ca release from the endoplasmic reticulum, triggered by autocrine activation of purinergic receptors after exocytotic release of ATP and/or ADP, and the spikes were consequently prevented by SERCA inhibition or P2Y-receptor antagonism. Widefield imaging, which monitors the entire cytoplasm, increased the spike detection by the Ca dyes. The indicator-dependent response patterns were unrelated to Ca binding affinity, buffering and mobility, and probably reflects the much slower dissociation kinetics of protein compared to dye indicators. Ca dyes thus report signalling within the submembrane space excited by TIRF illumination, whereas the protein indicators also catch Ca events originating outside this volume. The study highlights that voltage-dependent Ca entry in β-cells is tightly linked to local intracellular Ca release mediated via an autocrine route that may be more important than previously reported direct Ca effects on phospholipase C or on intracellular channels mediating calcium-induced calcium release.
Topics: Calcium; Insulin-Secreting Cells; Signal Transduction; Endoplasmic Reticulum; Coloring Agents; Calcium Signaling; Adenosine Triphosphate
PubMed: 37437828
DOI: 10.1016/j.cellsig.2023.110805 -
International Journal of Molecular... Dec 2023Lignosulfonate/polyaniline (LS/PANI) nanocomposite adsorbent materials were prepared by the chemical polymerization of lignosulfonate with an aniline monomer as a dopant...
Lignosulfonate/polyaniline (LS/PANI) nanocomposite adsorbent materials were prepared by the chemical polymerization of lignosulfonate with an aniline monomer as a dopant and structure-directing agent, and the adsorption behavior of dyes as well as heavy metal ions was investigated. LS/PANI composites were used as dye adsorbents for the removal of different cationic dyes (malachite green, methylene blue, and crystal violet). The adsorption behavior of LS/PANI composites as dye adsorbents for malachite green was investigated by examining the effects of the adsorbent dosage, solution pH, initial concentration of dye, adsorption time, and temperature on the adsorption properties of this dye. The following conclusions were obtained. The optimum adsorption conditions for the removal of malachite green dye when LS/PANI composites were used as malachite green dye adsorbents were as follows: an adsorbent dosage of 20 mg, an initial concentration of the dye of 250 mg/L, an adsorption time of 300 min, and a temperature of 358 K. The LS/PANI composite adsorbed malachite green dye in accordance with the Langmuir adsorption model and pseudo-second-order kinetic model, which belongs to chemisorption-based monomolecular adsorption, and the equilibrium adsorption amount was 245.75 mg/g. In particular, the adsorption of heavy metal ion Pb was investigated, and the removal performance was also favorable for Pb.
Topics: Coloring Agents; Lead; Metals, Heavy; Aniline Compounds; Ions; Lignin; Rosaniline Dyes
PubMed: 38203303
DOI: 10.3390/ijms25010133