Dye Effluent Research Articles

Determination of Radium concentration and Radon Exhalation Rates Using CR-39 Detector for Different Geopolymer Cement Samples Containing Industrial Wastes

Natural material like metakaolin, along with industrial wastes such as fly ash (FA), cement kiln dust (CKD), and ground granulated blast furnace slag (GGBFS), are being used to develop new affordable and environmentally friendly construction materials (Geopolymers) that result in reduced carbon dioxide emissions. Geopolymers are gaining attention for their ability to effectively remove organic and inorganic contaminants from wastewater, including dyes and heavy metals. However, the study of the radiation properties of eco-friendly geopolymer cement materials has received little attention. To address this gap, conducted a previous study to examine the radiation properties of different geopolymer cement samples. In this study, the analyzed the radon concentration, radium concentration, and annual effective dose of various pre-treated geopolymer cement samples that contained industrial wastes from dyes and heavy metals. By using the CR-39 detector as a passive technique for this examination. In the pretreated geopolymer cement samples, we used three types of reactive dye effluents - reactive black 5 (BD), reactive red 195 (RD), and reactive yellow 145 (YD) in the presence of heavy metals (Cu2+, Cd2+, and Pb2+). Based on our research, the concentration of radon ranged from 2.69 to 212.42 Bq m-3. The sample with the lowest value of radium concentration was labeled as (10) (GGBFS), while sample (9) (SF10-YD-Cu2+) had the highest value. Found that the annual effective doses were within the range of the world average for indoor and outdoor 1.55and0.58mSvy−1 respectively, except for sample 9 (SF10-YD-Cu2+) which had the highest radium concentration. The pretreated geopolymer cement mixes containing different dye effluents and heavy metals were found to be safe for use in construction areas, except for sample 9 (SF10-YD-Cu2+). Recommend using sample 9 (SF10-YD-Cu2+) only for public highways, bridges, and other well-ventilated buildings.

Assessment of de-toxicity of treated dye solution via seed germination test: Photocatalytic treatment by Morinda citrifolia leaf extract mediated ZnO:Mo/g-C3N4 nanocomposite

Molybdenum doped zinc oxide (ZnO:Mo) nanoparticles and ZnO:Mo/g-C3N4nanocomposites were prepared via green synthesis by using Morinda citrifolia (M. citrifolia) extract as the reducing agent. Another set of ZnO:Mo and ZnO:Mo/g-C3N4 nanomaterials were prepared using NaOH as the reducing agent and their photocatalytic efficiencies against methylene blue (MB) and methyl orange (MO) were evaluated and compared with those of their green synthesized counterparts. The degrading efficiency of green synthesized ZnO:Mo/g-C3N4 was 99 and 96 % against MB and MO of dyes, respectively, whereas the respective values in the case of chemical synthesis are only 95 and 90 %. The mechanism lies behind the photocatalytic activity of the nanocomposite was elaborated. The enhanced charge carrier concentration caused by Mo doping and the synergistic advantages of the composite partners, like band gap reduction and reduced recombination rate are discussed with relevant references. The water samples photocatalytically treated by the nanomaterials were applied to green gram seeds and the growth process is evaluated and compared. The powder XRD, field emission SEM, TEM, FTIR and EDAX results and the related analyses are presented as corroborative evidences for the composite formation and enhanced photocatalytic activity. The prepared green synthesized ZnO:Mo/g-C3N4 nanocomposite will be a promising material for de-toxification of dye effluents to make it conducive for seed germination and plant growth.

Innovative treatment of industrial effluents through combining ferric iron and attapulgite application

The escalation of industrial activities has escalated the production of pharmaceutical and dyeing effluents, raising significant environmental issues. In this investigation, a hybrid approach of Fenton-like reactions and adsorption was used for deep treatment of these effluents, focusing on effects of variables like hydrogen peroxide concentration, catalyst type, pH, reaction duration, temperature, and adsorbent quantity on treatment effectiveness, and the efficacy of acid-modified attapulgite (AMATP) and ferric iron (Fe(III))-loaded AMATP (Fe(III)-AMATP) was examined. Optimal operational conditions were determined, and the possibility of reusing the catalysts was explored. Employing Fe3O4 as a heterogeneous catalyst and AMATP for adsorption, CODCr was reduced by 78.38–79.14%, total nitrogen by 71.53–77.43%, and phosphorus by 97.74–98.10% in pharmaceutical effluents. Similarly, for dyeing effluents, Fe(III)-AMATP achieved 79.87–80.94% CODCr, 68.59–70.93% total nitrogen, and 79.31–83.33% phosphorus reduction. Regeneration experiments revealed that Fe3O4 maintained 59.48% efficiency over three cycles, and Fe(III)-AMATP maintained 62.47% efficiency over four cycles. This work offers an economical, hybrid approach for effective pharmaceutical and dyeing effluent treatment, with broad application potential.

Synergistic photocatalytic degradation of crystal violet dye using novel medical waste-derived carbon/ZnO composite: A study on toxicological assessment

The discharge of crystal violet (CV) dye effluents from textile sectors is a significant concern, as these pollutants not only diminish the aesthetic appeal of water bodies but also impede light penetration, thereby disrupting aquatic ecology. Additionally, the COVID-19 pandemic has led to increased usage of disposable face masks, further contributing to medical waste in the environment. In this state-of-the-art study, the aim was to develop a photocatalyst material using medical-waste-derived carbon (MWC) as a support matrix for zinc oxide (ZnO) nanoparticles, facilitating the photocatalytic degradation of CV dye via persulfate (PS) activation. X-ray diffraction and Raman spectroscopy were used to analyze the crystalline and chemical bonding properties of the synthesized photocatalysts, whilst field-emission scanning electron microscopy and transmission electron microscopy with energy-dispersive X-ray spectroscopy mapping were employed to examine the samples’ surface morphology and composition. The UV–vis spectroscopy and photoluminescence spectroscopy were used to confirm the optical properties of the photocatalysts. The degradation analyses showed that the MWC/ZnO nanocomposite achieved a higher degradation efficiency of 94.4%, with a reusability performance of 91.0% in the fifth cycle. Toxicology assessment was performed using seedling Vigna mungo plants and zebrafish, which revealed significant developmental deformities in the embryos and adults of zebrafish treated with the CV solution, but not when grown with the degraded CV solution or water, supporting the non-toxic nature of the degraded dye water. Therefore, the proposed MWC/ZnO nanocomposite could be suggested as a potential catalyst for CV dye degradation and an ideal solution for both aquatic and medical waste pollutants.

Optimization and modelling of magnesium oxide (MgO) photocatalytic degradation of binary dyes using response surface methodology

Textile industry dye effluent contains a mixture of different kinds of dyes. Many times, photocatalysis is targeted as a solution for the treatment of dye effluent from the textile industry. Many researches have been published related to the photocatalysis of single textile dyes but in the real-world scenario, effluent is a mixture of dyes. Magnesium oxide (MgO) is used as a photocatalyst to treat a mixture (binary solution) of Methylene blue (MB) and Methylene violet (MV) along with individual MB and MV dyes in this article. MgO shows remarkable photocatalytic activity at about 93 and 88% for MB and MV dye in binary solution within 135 min. Furthermore, to study the influence of process parameters, experiments are designed with the help of the central composite design (CCD), and Response surface methodology (RSM) is used to study the interactions between parameters. For this study, five parameters are selected i.e., Photocatalyst dosage, initial concentration of both dyes, time of exposure to the light source, and pH of the binary solution. The photocatalytic process is also optimized and finally optimization of process parameters is validated with an experiment. The result of the validation experiment is very close to the predicted photocatalytic activity.

Comprehensive study of Fenton reaction efficiency on textile wastewater treatment from dye solution to real effluent with emphasis on Fukui function analysis

This study investigated the continuous degradation monitoring of three reactive dyes, reactive yellow 176 (RY), reactive Blue 4 (RB) and reactive red 293 (RR), both in separate solutions and in a mixture, along with their corresponding dye bath and industrial dyeing effluent, using Fenton reaction. A kinetic study was conducted to compare the degradation efficiency of the studied solutions. This work provides important yield of dye degradation, where the results showed that RB, RY, and RR had 96.64 %, 92.47 %, and 73.27 % color removal, respectively, within a two-hour reaction time. The pseudo-second-order model fit well to describe the degradation of RR and RY, while the zero-pseudo-order model provided a better fit for RB. The dye mixture exhibited 57 % color removal, whereas the dyeing bath and real effluent showed 41 % and 36 % removal, respectively, over a two-hour reaction time. Moreover, significant reductions in chemical oxygen demand (COD) and biological oxygen demand over 5 days (BOD5) were observed, with the real effluent demonstrating a 73.91 % COD reduction and an 86.66 % reduction in BOD5. The COD and BOD5 reductions for the dye bath were 67.53 % and 95 %, respectively. Additionally, COD and BOD5 reductions of 72.96 % and 96.66 %, respectively, were observed for the dye bath. DFT calculations were employed to elucidate the regioselectivity of radical oxidation of the three reactive dyes by Fenton's reagent, providing insights into global and local reactivity descriptors. Toxicity studies further underscored the efficacy of the Fenton reaction in wastewater treatment. Additionally, UV–visible spectral analysis before and after 12 h of Fenton reaction revealed total discolouration and a reduction in UV and visible peaks across all reactions, indicating comprehensive dye degradation and reduction.

Preparation of polypyrrole-functionalized recycled cotton fiber as a renewable and eco-friendly cellulose-based adsorbent for water decolorization: Comprehensive batch and fixed-bed column study

Cotton fiber is a low-cost material made from renewable and eco-friendly cellulose and can be used for various applications. However, raw cellulose has a low capacity for capturing pollutants. In this study, recycled cotton fiber was modified with polypyrrole through a chemical oxidative polymerization approach to enhance its implementation and suitability for removing reactive orange 5 (RO5) and reactive yellow 15 (RY15) from aqueous solutions. The cotton/polypyrrole (cotton/ppy) was characterized using SEM, EDS FTIR, and XRD techniques. These analyses indicated that polypyrrole was successfully coated on the cotton fiber. The optimal conditions for maximizing adsorption efficiency, including contact time, concentration of dye, adsorbent dosage, pH levels, and temperature, were determined. RO5 and RY15 eliminations are enhanced in the acidic environment (pH=2, contact time (RO5: 120 min, RY15: 90 min, adsorbent dosage: 200 mg, dye concentration (RO5: 20 mg/L, RY15: 40 mg/L)). The best fit for the adsorption procedure of RO5 and RY15 is the Temkin isotherm model, which indicates a chemisorption process delivers viable mechanism for the adsorption of RO5 (R2 =0.992) and RY15 (R2 = 0.987). Moreover, pseudo-first-order is the leading kinetic model for both RO5 (R2 = 0.999) and RY15 (R2 = 0.995). Furthermore, the study of the fixed-bed column was carried out, showing that the service volume decreased as the flow rate increased. The removal efficiency for RO5 and RY15 exceeded 80% even after using cotton/ppy adsorbent eight times. Therefore, the sustainable polypyrrole-functionalized recycled cotton fiber adsorbent is an excellent choice to eliminate dye effluents.

Utilization of Eco‐friendly Copper Oxide Nanoparticles and Iron Oxide Nanorods in Dye Removal from Real Textile Industry Effluent

AbstractTextile industry wastewater contaminated with dye effluents poses a significant environmental challenge. Numerous nanoparticles are used as adsorbents to treat similarly stimulated wastewater, but particularly nanomaterials synthesized through green methods have gained prominence. To assess their practical applicability in addressing real‐world textile wastewater pollution, studies on dye removal from authentic textile industrial effluents are recommended. As a result, a study focused on the removal of dye from real textile industrial effluent is conducted, and biosynthesized copper oxide nanoparticles and iron oxide nanorods are chosen as adsorbents. The investigation scrutinized the influence of adsorbent dosage, adsorbent‐adsorbate contact time, and wastewater pH on the percentage of dye adsorption. These findings indicate that increasing the adsorbent dosage and contact time leads to a higher percentage of dye removal. Notably, copper oxide nanoparticles exhibit superior dye removal efficiency at pH levels 5 and 7, outperforming the maximum dye removal efficiency of iron oxide nanorods at pH 12. The study achieved an impressive process efficiency of 95.24% for copper oxide nanoparticles and 62.5% for iron oxide nanorods. Response surface methodology (RSM) is employed for statistical data analysis and optimization of dye removal process parameters to maximize efficiency. Overall, the results demonstrate that biosynthesized nanomaterials offer a promising and effective solution for removing dyes from textile industrial wastewater.

Multiplexed colorimetry collaborated with smartphone-based image analysis for simultaneous and fast visualization of dyes in both environmental and food samples

In this work, a multiplexed colorimetric strategy was initiated for simultaneous and fast visualization of dyes using low-cost and easy-to-prepare indicator papers as sorbents. Response surface methodology (RSM) was employed to model statistically and optimize the process variables for dyes extraction and colorimetric assays. Multiplexed colorimetry was realized by virtue of synchronous color alignments from different dimensions of multiple dyes co-stained colorimetric cards under RSM-optimized conditions, and smartphone-based image analysis was subsequently performed from different modes to double-check the credibility of colorimetric assays. As concept-to-proof trials, simultaneous visualization of dyes in both beverages and simulated dye effluents was experimentally proved with results highly matched to HPLC or spiked amounts at RSM-predicted staining time as short as 50 s ∼3 min, giving LODs as low as 0.97 ± 0.22/0.18 ± 0.08 μg/mL (tartrazine/brilliant blue) for multiplexed colorimetry, which much lower than those obtained by single colorimetry. Since this is the first case to propose such a RSM-guided multiplexed colorimetric concept, it will provide a reference for engineering of other all-in-one devices which can realize synchronous visualization applications within limited experimental steps.

Comparing Color Strength Results through Analysis of Rinse Water between Wool Dyed with Onion Skins and Mordants and Synthetic Dye

The textile industry is one of the biggest global polluters releasing chemicals into the air, land, and water. The majority of these emissions are due to the chemicals that enter the water stream from the textile dyeing process. While synthetic dye effluents are very hard to remove from the wastewater, natural dyes have a very minimal effect on the environment due to their biodegradability. One major issue that prevents the textile industry from using natural dyes is the differences in colorfastness between the synthetic dyes and natural dyes. Because of this, this study will evaluate if the use of a mordant before fiber dyeing could increase the colorfastness of a natural dye so that the use of natural dyes can be increased in the textile industry. Harvesting a dye from yellow onion skins has proved to be an attractive dye product not only due to its color performance but since it is a natural waste product, not interfering in the food supply chain. Dye from onion skins was compared to a synthetic dye counterpart, Rit brand dye. One wool sample was dyed with Rit, and three others with the onion dye without a mordant, and with lemon juice or iron ferrous sulfate as mordants. These samples were then washed until the rinse water became clear. The rinse water was then evaluated with a UV-visible spectrophotometer. The KubelkaMunk theory was used to solve for color strength of the rinse water or how much dye bled from the wool during washing. In conclusion the Rit dye and the onion dye with the lemon mordant performed better than the onion dyes without a mordant and with an iron mordant.

Green synthesis of silver nanoparticles from Hibiscus tiliaceus L. Leaves and their applications in dye degradation, antioxidant, antimicrobial, and anticancer activities

The present study reports the green synthesis of silver nanoparticles (AgNPs) from aqueous extract of Hibiscus tiliaceus L. leaves and their application in dye degradation, antioxidant, antimicrobial, and anticancer activities. Analysis using Fourier transform infrared (FT-IR) spectroscopy revealed that plant metabolite functional groups had a role in the reduction and stability of AgNPs, and X-ray crystallography (XRD) demonstrated that the AgNPs were in crystal form. The UV–vis spectroscopy, dynamic light scattering (DLS), and zeta potential investigations revealed that the AgNPs were formed with an average size of 88.10 nm in colloidal form and were stable (-49 mV). The field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) confirmed the shape and size of the AgNPs as spherical with a particle size of 30 - 35 nm, respectively. The AgNPs exhibited potential antioxidant activity by total antioxidant, DPPH, and reducing power assays. The biosynthesized AgNPs displayed a wide range of antibacterial activity on Gram-ve and Gram+ve bacteria by the zone of inhibition assay. AgNPs showed good anticancer activity on MCF-7 cells with an IC50 value of 65.83 µg/mL. Furthermore, AgNPs acted as potential catalysts in combination with the reducing agent sodium borohydride (NaBH4) for the degradation of methylene blue (MB), methylene orange (MO), and methylene green (MG) dyes. The degradation efficiency of catalyst AgNPs in the attendance of NaBH4 for 15 min was noted to be 12.8 %, 26.92 %, and 47.56 % for MO, MB, and MG, respectively. The study concluded that green synthesized AgNPs could be highly applicable as an antioxidant, antimicrobial, and anticancer agents in the biomedical field. Furthermore, AgNPs could be helpful in the remediation of dye effluents.

Exploring indigenous fungal isolates for efficient dye degradation: A comprehensive study on sustainable bioremediation in the total environment

Synthetic dyes used in textile industries are hazardous and toxic to the environment, as some of the dyes used in these industries are non-biodegradable. Sustainable technologies using microbes are an eco-friendly and economical approach. Fungal decolorization processes are gaining much importance as biomass absorbs enzymes used in biodegradation. In the current study, six samples of dye wastewater were collected from different industries in the Faisalabad industrial area in Pakistan. The physiological characteristics of these samples were analyzed, and various parameters, including pH, temperature, BOD, COD, and electric conductivity, were investigated. Among six different (sample A-F) wastewater samples, the maximum reduction in BOD was observed in sample E, i.e.,1.3.In contrast, the maximum reduction in COD of sample C, i.e., 30, was observed. These samples' hydrogen ion concentration (pH) was mainly in an alkaline ratio, and a maximum electric conductivity of 8810 µS/cm of sample A was observed. In contrast, a minimum sample E (540 mg/L) was observed. Three indigenous fungal strains were screened and purified from dye wastewater for detoxification of dyes and were identified morphologically and on a molecular basis as Aspergillus iranicus, Penicillium crustosum, and Aspergillus terreus. A comparative analysis of two methods, the tube overlay method and the liquid medium method, were conducted to biodetoxification synthetic dyes, including malachite green, methylene blue, and nigrosine. Spectrophotometric analysis showed that indigenous fungal strains, i.e., Penicillium crustosum decolorizing methylene blue at about 93%, followed by Aspergillus iranicus decolorizing malachite green at about 80% and Aspergillus terreus decolorizing about 90% of malachite green have good potential for degradation of dyes. These strains can be a potential source for treating textile dye effluent.

Statistical Optimization and Kinetic Studies of Water Hyacinth Stem–Based Activated Carbon Adsorbent for Synthetic Textile Dye Effluent Treatment

Statistical Optimization and Kinetic Studies of Water Hyacinth Stem–Based Activated Carbon Adsorbent for Synthetic Textile Dye Effluent Treatment

Industrial dye effluent degradation and in-vitro biological characteristics of MgO NPs anchored few layered g-C3N4 nanoribbons

In recent years, contaminated water consumption by humans and animals are lead to various types of diseases and environmental pollutant. Especially textile dye effluents are the highest contaminants in water bodies than any other industries. This article reports a green process for synthesizing MgO nanoparticles supported by the exfoliated g-C3N4 nano composites for dye effluent treatment. The cubic and hexagonal phase structure was achieved for synthesized MgO NPs and E-GCN, respectively, with spherical and curled ribbon-like morphology. The specific surface area was measured as 70.48, 54.22, and 79.11 m2/g, respectively, for MgO NPs, E-GCN, and MgO/E-GCN nanocomposite. Similarly, corresponding optical properties were achieved with an energy gap of 3.42, 2.48, and 2.78 eV. XPS analysis confirms the formation of MgO/E-GCN nanocomposite by detecting their characteristic elemental peaks. The bioactivities including antibacterial, turbidimetric, and antioxidant efficacy, were also investigated. Thus, the MgO/E-GCN nanocomposites was exhibitd greater susceptibility against pathogenic bacteria due to its production of high reactive oxygen species. Further, the catalysts were used to degrade cationic dye (Crystal Violet) and anionic dye (Eosin Yellow) under sunlight exposure. The photocatalytic efficiency of MgO/E-GCN nanocomposite was highly influenced towards CV (98.9 %) and EY (97.33 %) dye degradation, because of its high surface area with active UV–Visible region. Therefore, the combination of naturally inspired MgO NPs and morphologically modified E-GCN nanocomposites are being a sustainable material development for environmental remediation and biological applications.

Adsorptive removal of methylene blue dye using durian peel waste reinforced polyvinyl alcohol‐based composite membrane

AbstractA large amount of dye effluents with biodegradable and highly toxic nature from the dyeing and finishing processes has discharged into natural water bodies without adequate treatment, which adversely impacted on aquatic life and human health. Herein, polyvinyl alcohol/agarose/maltodextrin composite membrane (PAM)‐reinforced durian skin fiber is fabricated for methylene blue (MB) uptake from aqueous medium. Structural analyses of the as‐prepared composite membrane are conducted using scanning electron microscopy, Fourier‐transform infrared spectroscopy, water contact angle, and nitrogen adsorption/desorption isotherm measurement. The important influence of experimental conditions including exposure time between adsorbates and adsorbents, initial MB concentration, solution temperature, and pH are also explored. Furthermore, thermodynamic behavior, nonlinear isotherms, and kinetics along with possible adsorption mechanism are provided to attain the insight into the adsorption nature. The results show that PAM‐reinforced durian peel waste possesses high MB adsorption capacity (105.54 mg g−1), which was controlled by diffusion and chemisorption mechanism. The thermodynamics of methyl blue removal on the composite membrane suggest that the adsorption is spontaneous, favorable, and endothermic in nature. This contribution is expected to inspire the efficient utilization of agriculture by‐products into eco‐friendly and biodegradable adsorbents to purify the dye‐contaminated water.

Controlled solvothermal synthesis of self-assembled SrTiO3 microstructures for expeditious solar-driven photocatalysis dye effluents degradation

In this work, the self-assembled SrTiO3 (STO) microstructures were synthesized via a facile one-step solvothermal method. As the solvothermal temperature increased from 140 °C to 200 °C, the STO changed from a flower-like architecture to finally an irregularly aggregated flake-like morphology. The photocatalytic performance of as-synthesized samples was assessed through the degradation of rhodamine B (RhB) and malachite green (MG) under simulated solar irradiation. The results indicated that the photocatalytic performance of STO samples depended on their morphology, in which the hierarchical flower-like STO synthesized at 160 °C demonstrated the highest photoactivities. The photocatalytic enhancement of STO-160 was benefited from its large surface area and mesoporous configuration, hence facilitating the presence of more reactive species and accelerating the charge separation. Moreover, the real-world practicality of STO-160 photocatalysis was examined via the real printed ink wastewater-containing RhB and MG treatment. The phytotoxicity analyses demonstrated that the photocatalytically treated wastewater increased the germination of mung bean seeds, and the good reusability of synthesized STO-160 in photodegradation reaction also promoted its application in practical scenarios. This work highlights the promising potential of tailored STO microstructures for effective environmental remediation applications.

Catalytic thermal treatment (catalytic thermolysis) of textile dyeing effluent

During the production of textiles a large amount of wastewater is generated that contains high organics load and color appearance. If it is directly (untreated) discharged into any water-receiving body then it gets fully contaminated, hence its proper treatment is required. The present study deals with the treatment of textile dyeing effluent (TDE) using catalytic thermolysis (CT) for the reduction of color and COD reduction with the help of CuO as a catalyst. The catalyst (CuO) was prepared successfully on the laboratory scale. The CuO preparation is done by alkali precipitation of copper sulfate followed by drying and calcination. Catalyst is characterized in detail including X-ray diffraction, SEM, and TEM analysis. CT treatment of TDE was carried out in a 0.5 dm3 thermolysis batch reactor using CuO as a catalyst at different pH (2.4–10.4), temperatures (70 °C–115 °C), and catalyst loadings (1.5–5.5 g/dm3). The maximum 72 % COD reduction was achieved at the optimum condition of 70 °C temperature, catalyst loading of 1.5 g/dm3, and 4.4 pH. The residues obtained after CT were characterized by TGA, TDA, and TG. In addition, settling characteristics were also observed for CT-treated sludge at different temperatures. CT is a novel treatment technique to treat highly polluted wastewater. During the CT treatment, the addition of chemicals is not required and it has good removal efficiency. Further CT-treated sludge has good heating value hence it can be used as an industrial fuel. In other words, no secondary pollutants are generated during the CT process.

Continuous ultrasonic ozone coupling technology-assisted control of ceramic membrane fouling coupled enhanced multiphase mixing to treat dye wastewater and CFD flow field simulation

In this study, ozone catalysts (hydrogenation-modified red mud, HM-RM) successfully prepared by hydrogenation-modification of industrial hazardous solid waste red mud (RM) as a raw material in accordance with the viewpoint of treating waste with waste and using waste. Meanwhile, as for the common phenomenon of membrane fouling, uneven distribution of multiphase solid catalysts and ozone in liquids, the addition of ultrasound can not only disperse materials, but also play a role in online cleaning of ceramic membranes and catalysts. The optimum treatment conditions for Rhodamine B (RhB) solution with volume of 2 L and concentration of 40 mg/L were catalyst concentration of 0.4 mg/L, reaction temperature of 45 °C, ultrasonic time of 1 h, ultrasonic intensity of 600 W, removal rate of RhB was up to 90 %. In addition, the computational fluid dynamics (CFD) simulation method was used to investigate the fluid flow between the two gas-liquid phases and the effect of the negative pressure of the membrane pump on the fluid by the analysis of flow, pressure and ozone flux of the ceramic membrane(CM) reaction apparatus. The CFD simulation results showed that at the inlet gas-liquid flow rate of 3 m/s and the negative pressure of 20,000 Pa, the maximum flow rates of CM-1 were 3 m/s, 0.752 m/s for CM-2, and 0.228 m/s for CM-3, respectively. Vortices, which are beneficial to solid-liquid mixing and gas-liquid mass transfer, formed between the suction port CM-1 of CM-1 and the inlets of CM-2 and CM-3. This discovery is consistent with relevant experimental research results. Significantly higher concentrations of both •OH and dissolved ozone were observed in the US/HM-RM/O3 system compared to other systems, indicating the significant improvement in ozone utilization rate through the application of ultrasound. The superiority of the US/HM-RM/O3 device was demonstrated. The real dye effluent was tested under optimum operating conditions and the results showed that COD and TOC were reduced by 81.34 % and 60.23 % respectively after 180 min of treatment. The above research can provide technical support for the treatment of dye wastewater using Ultrasound-enhanced ozone oxidation ceramic membranes.

Photocatalytic Degradation of Rhodamine B under UV Light Catalyzed by Alpha Titanium Phosphate and Metal Modified Titanium Phosphate

Wastewater management is a crucial issue in most emergent nations with ever-growing global industrialization. From textiles to food, mankind uses dyes and pigments which pose a threat to the environment due to organic non-biodegradable dyes contained in wastewater. Rhodamine B (RhB) is a conventional colorant in many industries producing a large amount of dye effluent, thus becoming a serious threat to the environment as well as human health. Additionally, RhB is dangerous even at extremely low quantities, making treatment of the RhB effluent more essential. Even though TiO2 is considered as the best photocatalyst to remove many organic pollutants, acceptable alternatives are needed due to being uneconomical in large-scale usage. Synthesis of titanium bismonohydrogen orthophosphate (α-TiP) can be achieved by refluxing ilmenite with phosphoric acid via a previously reported novel method. Solid state reactions of α-TiP and oxides of Co and Cu at 800° C result in various metal titanium phosphates (M-TiP) with unique colors. XRD, FTIR, and Diffuse reflectance UV-vis techniques were used for characterization of the obtained solids. Bandgap of α-TiP changed with the modification of different transition metal cations lowering bandgap from 4.01eV (α-TiP) to 3.57 eV (Cu-TiP). Aqueous RhB degradation under UV irradiation was used to investigate the photocatalytic abilities of these catalysts. For that 0.2 g sample of catalyst was added to a solution that contained 200 mL of a 5 mg L-1 Rh B which was kept for 15 mins in dark to reach adsorption-desorption equilibrium before exposing the sample to UV irradiation for 3 h. A clear enhancement of photocatalytic activity was observed from using Co- TiP as the catalyst, which only took around 80 min to remove almost all Rh B contained in the sample compared to α-TiP which took close to 3 h to become colorless. It was in alignment with spectrometer results where a clear reduction of intensity can be seen in wavelength at 552 nm. Photocatalytic activities of these catalysts decreased in the following order: Co-TiP>α-TiP>Cu-TiP. The Co-modified TiP showed degradation of 99.5% after 3 h of UV irradiation and pseudo first- order kinetics were followed by the degradation. 
 Keywords: Titanium Phosphate, Photocatalyst, Rhodamine B, Wastewater management

Fenton-mediated solar-driven photocatalysis of industrial dye effluent with polyaniline impregnated with activated TiO2-Nps

Various integrated technologies have been investigated for the remediation of heavily polluted industrial dye effluent. Also, more than 70 % of these dyes are known to be solely azo dyes used in the textile industry with 5–30 % presence in the effluent as loose dye molecules which are recalcitrant to treatment. These challenges led to the investigation of energy-efficient processes (solar) and the fabrication of high-performance nano-photocatalysts for proficient photocatalysis of dye effluent while mediating the process with Fenton reagents. The study fabricated nanopolymeric catalyst composites (P-AKT) via novel in situ coupling and impregnation of the polyaniline (PANI) with surface-activated TiO2 NPs. This fabrication is aimed at developing a high-performance catalyst with rapid and proficient photocatalytic activities to photons from sunlight irradiation. The photocatalytic process was mediated using a novel Fenton reagent to enhance the generation of radical species for dye degradation. Various instrumental characterization methods were used to study the structural, molecular, elemental, functional and optoelectronic properties of the fabricated nanocomposite photocatalysts. The result reveals functional groups aiding dye-catalyst bonding and morphological interaction reveal a surface-activated tetragonal crystalline mixture of anatase and rutile from TiO2−Nps embedded in the macromolecular chain of PANI. It also reveals the optimal conditions of 20 mg dosage, 10 mg/L initial concentration with substantial effectiveness at pH of 5 and 7. However, the most efficient photocatalyst recorded was P-AKT-2 % and P-AKT-3 % having 95 % and 94 % efficiencies at 90 min of solar irradiation. The photocatalyst equally demonstrated its capacity for effluent treatability up to 4 cycles of use.