Papers by Keyword: Methylene Blue

Abstract: In this work, photoelectron nanocomposites of TiO₂&CeO₂&Ag were synthesized by a co-deposition method using TTIP (Titanium TetraIsoPropoxide) and water solutions of Ce(NO₃)₃ and AgNO₃. Heat treatment of the precipitates at 600°C led to the formation of an anatase phase with the primary particles’ size of 14.1–15.2 nm. Molecules of Malachite green and Methylene blue are intensively adsorbed on the surface of nanocomposites. TiO₂&CeO₂&Ag nanocomposites show high photocatalytic activity to cationic dyes and weak – to anionic ones. The photocatalytic decomposition of cationic dyes is accompanied by a hypsochromic shift of chromophoric bands. Only the chromophoric part of the dye molecules is destroyed by temperature (catalytic process). Nanocomposites based on anatase containing 1–2 wt.% of Ag and Ce show the highest photocatalytic activity for the destruction of organic dyes.

Abstract: Methylene Blue (MB) waste is damaging to both humans and the environment. Chitosan is one of the MB adsorbents that may be made from green mussel shells. Because CS compounds have a limited adsorption capacity for MB, a restricted surface area, and poor chemical stability, thus necessitating modification. CS/XG was created by combining the three chemicals silica (SiO₂), tofu pulp, and the anionic substance Xanthan Gum (XG). SiO₂ hydrogel bio-composite with the aid of UV light, can absorb MB by photodegradation. The objective of this paper is to analyze the regeneration and photocatalysis kinetics based on the kinetic rate constant of the bio-composite photodegradation, and to identify the ideal circumstances of MB photodegradation by CS/XG.SiO₂ hydrogel bio-composite with Box-Behnken design. The CS/XG bio-composite was synthesized from chitosan (green mussel shell waste) and xanthan gum (tofu dregs waste) with added SiO₂ to adsorb methylene blue via photodegradation. The use of green mussel shells and tofu dregs is significant as it turns abundant waste into valuable materials, reducing pollution and supporting low-cost, eco-friendly wastewater treatment.The variables were pH, MB concentration, and photodegradation time. The results showed that the optimum condition occurred at pH 9.43; MB concentration 5.054 ppm; and irradiation time 119.67 minutes with % degradation of 94.2%. After the 5th reuse of CS/XG.SiO₂, the % degradation only decreased from 94.2% to 79.4%, indicating good regeneration ability. Analysis of photodegradation kinetics showed accurate modelling using the Modified Elovich model with an R² value of 0.9805 and a photodegradation kinetic rate constant of 0.0010 min^-1.

Abstract: Fe₃O₄/CDots nanocomposites by combining Fe₃O₄ synthesized using Moringa oleifera extract and CDots produced from watermelon rinds have been successfully carried out. The Fe₃O₄/CDots nanocomposites with various CDots concentration was carried out through a sonication process. Test results using an X-ray diffractometer show that the crystal structure of the nanocomposite is a cubic inverse spinel. The presence of CDots resulted in a decrease in the size of Fe₃O₄ crystallites from 10.6 nm to 8.4 nm. Fourier transform infrared analysis confirmed the formation of Fe₃O₄/CDots nanocomposites with the appearance of Fe-O and C=C functional groups. The absorbance spectrum of the nanocomposite shows a dominant profile of Fe₃O₄/CDots, with an increase in band gap energy by the increase of CDots concentration in the range of 2.65 – 2.77 eV. The attachment of CDots to Fe₃O₄ is indicated by the luminescence produced in the photoluminescence test. The magnetic properties of Fe₃O₄ and Fe₃O₄/CDots nanocomposites show superparamagnetic characteristics with saturation magnetization values ​​of 54.2 emu/g and 34.3 emu/g, respectively. The magnetic properties of Fe₃O₄/CDots nanocomposites can support the separation feature of the liquid phase with the help of an external magnet. In testing photocatalytic activity, it was able to degrade methylene blue organic dye waste up to 96.7% in 10 minutes of UV radiation. Therefore, Fe₃O₄/CDots have potential as promising heavy metal removal agents and photocatalysts for effective and efficient environmental remediation.

Abstract: Research has been conducted on Fe₃O₄/PEG material applied as a photocatalyst. This research is motivated by the many textile industries that pollute the environment with their liquid waste disposal. The purpose of this research is to analyze the effect of concentration variation of Fe₃O₄/PEG nanocomposites that are green synthesized using Moringa oleifera extract on the photodegradation efficiency of Methylene Blue (MB) dye in water. The nanocomposites formed were then characterized through several techniques, including X-Ray Diffraction, Fourier Transform Infrared Spectroscopy, Vibrating Sample Magnetometer, and Ultraviolet-Visible (UV-Vis) spectrophotometry. Afterwards, the nanocomposites were tested in the MB photocatalytic process with various concentration to determine their effect on the degradation efficiency under UV irradiation. The material characterization results show that the nanocomposites has an inverse spinel cubic crystal structure with a crystallite size of 15.93±0.03 nm, and a lattice parameter of 8.17 Å. UV-Vis analysis showed an absorption peak at a wavelength of 322 nm with a direct energy band gap of 3.8 eV, and properties towards superparamagnetic with a saturation magnetization of 49.9 emu/g. Photocatalytic tests showed an increase in efficiency as the catalyst concentration increased, reaching the highest degradation of 68.2% at a mass of 0.09g. Therefore, this nanocomposite has potential as a photocatalyst.

Abstract: The textile industry in Indonesia is currently rapidly growing. However, this increase harms the environment because dyes from textile production are generally released into the environment without prior processing. Photocatalysis is one effort that can be used to overcome this problem. TiO₂ has been proven to be highly efficient in its work as a photocatalyst material. This study aims to investigate the effectiveness of methylene blue (MB) photodegradation using TiO₂ with steady pre-treatment optimizations. The pre-treatment was carried out by leaving the mixture of TiO₂ and methylene blue in various conditions under dark and room light conditions, resulting in ⁓37% and ⁓50% degradation efficiencies, respectively. Higher total percent MB degradation efficiencies (%Eff) were reached after visible light irradiation using mercury lamp in the post-treatment of more than 75%, concluding that the pre-treatment both in dark and room light storage optimized the MB degradation process. Therefore, these pre-treatment methods are potentially suitable for industrial wastewater treatment before the photocatalysis process to lower the waste management cost.

Abstract: Increasing textile production leads to a corresponding rise in dye waste, including substances such as methylene blue. Methylene blue poses a significant environmental challenge due to its non-biodegradable nature and high toxicity, which can adversely affect both human health and ecosystems. To address this issue, various methodologies have been explored, with adsorption emerging as a promising technique. This study focuses on employing adsorption utilizing an adsorbent derived from patchouli dregs and activated using hydrochloric acid (HCl). The research commenced with the pyrolysis of patchouli dregs at different temperatures: 300°C, 340°C, and 380°C for 1.5 hours. Subsequently, chemical activation was carried out using HCl solutions with concentrations of 0.3 M, 0.5 M, and 0.7 M. The resulting activated adsorbent underwent characterization to assess its morphological structure, functional groups, and crystalline composition. The scanning electron microscopy (SEM) analysis revealed prominent pores in the patchouli dregs adsorbent post-activation, with a size of 14.699 μm. X-ray diffraction (XRD) analysis demonstrated an irregular microcrystalline structure and amorphous nature of the activated patchouli dregs adsorbent. Additionally, Fourier transform infrared (FTIR) analysis identified active functional groups including O-H, C=O, C=C, C≡C, and C=H, which facilitate methylene blue adsorption. Characterization of the various iterations of the patchouli dregs adsorbent confirmed its suitability for methylene blue adsorption, meeting the quality standards outlined in SNI 06-3730-1995. These standards include a water content of 1.935%, ash content of 7.568%, and iodine adsorption capacity of 1,270.41 mg/g. In summary, this study elucidates the potential of patchouli dregs-derived adsorbents activated with hydrochloric acid for effective methylene blue removal, providing insights into their morphological, structural, and functional characteristics crucial for addressing the challenges associated with textile dye waste management.

Abstract: This study focuses on synthesizing and characterizing a semi-Interpenetrating Network (semi-IPN) elastomeric hydrogel comprising natural rubber (NR) and polyethylene glycol methacrylate (PEGMA) for efficient removal of Methylene Blue (MB) dye from aqueous solutions. The impact of varying PEGMA/NR ratios (100/0 to 0/100) was investigated. SEM images displayed a porous and uniform structure with interconnected pores of different sizes. FTIR analysis confirmed the formation of a semi-IPN structure, showcasing functional groups in both NR and PEGMA. Adsorption studies revealed the hydrogel's efficacy in MB dye removal, achieving a maximum adsorption capacity of 6536 mg/g at a PEGMA/NR ratio of 90/10. UV-vis spectroscopy validated the reduction in MB concentration post-exposure to the hydrogel. These findings highlight the cationic ionic nature of the PEGMA/NR semi-IPN elastomeric hydrogel as a promising adsorbent for MB dye removal in wastewater applications, particularly in industrial wastewater treatment.

Abstract: In view of the growing concern over the threat of antibiotic resistance and bacterial infections, this study evaluated the antimicrobial performance and characteristics of chitosan/polyvinyl alcohol (PVA) nanofibers incorporated with Methylene Blue (MB). Following the fabrication of chitosan/PVA nanofibers loaded with different MB concentrations via electrospinning, the samples were characterised through Field-emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared (FTIR) spectroscopy, and leaching tests. Finally, the antimicrobial inhibition level of the samples was assessed via the disc diffusion method. Based on the results, the MB-integrated chitosan/PVA nanofibers exhibited a nanoscale morphology, and the FTIR confirmed the presence of MB. The findings also established a positive correlation between the MB concentration and leaching intensity. Furthermore, the optimal antimicrobial efficacy against Escherichia coli was achieved by the chitosan/PVA/MB (5 wt.%) sample with a 2-min laser exposure, which recorded a significant inhibition zone of 8.65 mm. In conclusion, MB demonstrated potent antimicrobial properties against E. coli, suggesting its potential integration in electrospun nanofibers for combating bacterial infections via photodynamic therapy.

Abstract: Accumulation of untreated and unrecycled paper has a negative impact on the environment. Like liquid waste handling, paper waste handling is also still being developed. It is known that activated carbon (AC) is one of the promising adsorbents that can be used to solve the environmental issue. Activated carbon can be made from organic waste, such as waste paper. The objective of this study is to investigate the operation condition of the pyrolysis process to obtain the activated carbon. The furnace temperature was set at 400°C for 1 hour under N₂ stream with a flow rate of 0.5 L/min. To provide a synergistic effect in the adsorption process, ZnO was derived from ZnCl₂ as a chemical activator for making active carbon. While Zn (CH₃COO)₂.2H₂O with different concentrations of 0.01, 0.05, and 0.1 M was grown into the pores of activated carbon. The photocatalytic activity of AC/ZnO was identified in the degradation process of methylene blue as a model of organic pollutants. X-ray diffraction (XRD), scanning electron microscope (SEM), and fourier transform infrared (FTIR) were used to characterize the product. The morphology of ZnO was observed in the form of a flower-like and occupying the surface of activated carbon. The photocatalytic activity showed that the methylene blue was completely degraded.

Abstract: Cyclodextrin metal-organic frameworks (CD-MOFs) are synthesized from green precursors, making them an ideal material for green adsorbents. However, CD-MOFs are unstable in water, thus limiting their applications. Here, we report encapsulating CD-MOFs in polyacrylonitrile (PAN) and polyvinylpyrrolidone (PVP) polymeric support to produce PAN/PVP/CD-MOF composite beads. Batch adsorption studies showed that high dye adsorption capacities could be obtained at intermediate PVP, high PAN, and low CD-MOF loadings. Maximum MB and CR sorption capacities under optimum bead formulation: PAN = 6.96 wt.%, PVP = 2.20 wt.%, and CD-MOF = 2.88 wt.%. The optimized composite beads have a sorption capacity of 37.40 mg/g for MB and 18.42 mg/g for CR. We showed that PAN/PVP/CD-MOF composite beads could be an excellent adsorbent for textile dye removal in water.