Treatment Of Methylene Blue Wastewater Research Articles

Treatment of methylene blue wastewater with nano-PbCrO4 photocatalyst prepared from chromite ore processing residue

Chromite ore processing residue (COPR) is an environmental threat due to its content of Cr (Ⅵ) which is a highly toxic substance. However, some metallic elements in COPR can create the intrinsic values of COPR. In this study, the nano-lead chromate (PbCrO4) was prepared by the chemical precipitation method for the water-soluble Cr (VI) leachate obtained by the simple water washing of COPR and the use of methylene blue (MB) degradation. Results demonstrated that the prepared lead chromate had good photocatalytic performance and stability. The degradation rate of MB was 76.78% with the conditions of the initial pH was 6, the initial concentration was 10 mg/L, the reaction time was 80 min, and the photocatalyst dosage was 1.0 g/L. Moreover, recycling results displayed that the degradation rate remained at 62.91% after five cycles which means it can be recycled. Meanwhile, the concentration of Cr (VI) in COPR decreased from 34.7 to 1.4 mg/L which is below the national emission standard of China (GB 5085.3–2007), that is 5 mg/L, achieving harmless treatment of COPR. Consequently, this study provides a new tactic for the resource utilization of COPR, and implements the governance concept of “waste control by turning waste into treasure”.

High‐Efficiency Adsorption Performance of Cobalt Alginate/ Graphene Oxide Aerogel Prepared by Green Method for Methylene Blue

AbstractIn this paper, cobalt alginate/graphene oxide (CA/GO) aerogel composites were prepared by wet spinning and vacuum freezing. The cobalt ion only ion‐pairs with the carboxyl ion in the alginate, and other groups such as hydroxyl were not combined with cobalt ions, generating free hydroxyl, and thus improving the adsorption performance and recyclability of the composite material. The adsorption properties of CA/GO aerogels gradually improved with the increase of pH. The maximum adsorption capacity of CA/GO aerogel at 298 K was 294.18 mg.g−1, and the adsorption process of methylene blue (MB) on CA/GO aerogel conformed to Langmuir isotherm model and pseudo‐second‐order model. The adsorption of MB on CA/GO is mainly attributed to electrostatic attraction, hydrogen bonding and π‐π interaction. Thermodynamic analysis showed that the adsorption process was both spontaneous and exothermic. After the CA/GO aerogel was reused for 5 times, the removal rate reached as high as 80.256 %. Compared with other adsorbents, the prepared adsorbent was proven to be provided with good removal capacity for MB, and expected to be widely applied to the adsorption treatment of MB wastewater.

Biosynthesis of Tithonia diversifolia leaf mediated Zinc Oxide Nanoparticles loaded with flamboyant pods (Delonix regia) for the treatment of Methylene Blue Wastewater

The large capacity of wastewater production due to rapid growth of industries has resulted in limited water resources. The need to protect and conserved water resources have enforced researchers worldwide to focus on the development of an effective, economical and environmentally friendly novel materials. In this study, green synthesis of zinc oxide nanoparticles (ZnONPs) using T. diversifolia leaf extract by hydrothermal method was loaded on the surface of flamboyant pods (Delonix regia) activated carbon (FPAC). The developed ZnONPs loaded on the surface flamboyant pods activated carbon (ZnONPs-FPAC) was used successfully to remove of methylene blue (MB) from aqueous solution. The developed FPAC, ZnONPs and ZnONPs-FPAC were characterized UV–Vis spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX), Transmission electron microscope (TEM) and Brunauer-Emmett-Teller (BET) techniques. The antibacterial activity of the synthesized FPAC, ZnONPs and ZnONPs-FPAC were screened and the results revealed that ZnONPs has an excellent antibacterial activity when compared. Batch adsorption studies were conducted to investigate the influence of process parameters such as initial concentration, contact time, pH, adsorbent dosage and temperature on MB uptake. The high BET surface area of 794.48 m2/g and mesoporous ZnONPS-FPAC developed gave good adsorption capacity of 186 mg/g. Equilibrium adsorption data of MB were modelled using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D–R) isotherm model. The adsorption of MB onto ZnONPs-FPAC was best described by Freundlich model indicating surface heterogeneity, and pseudo-second-order kinetics according to %Δqe (normalized standard deviation), SSE (sum of square error), and R2 (coefficient of determination) values. The results of the thermodynamic suggest that the adsorption process of MB onto ZnONPs-FPAC is endotherm, favourable, spontaneous, and physical. In nature. The reusability of ZnONPs-FPAC was examined upto five cycles with no significant loss in removal efficiency. The mean free energy (E), and Enthalpy (ΔH) values calculated, suggested that the adsorption mechanism of MB on ZnONPs-FPAC is dominated by physical adsorption.

Experimental Research on Treatment of Methylene Blue Wastewater by Fe3O4-MnO2 Fenton System

In order to broaden the processing conditions of the Fenton method, under the premise of adding a catalyst, the operating conditions of the Fenton-like system were studied. When studying Fe3O4-MnO2-PAC composite material as a catalyst,this experiment find the influence of different single factors on the Fenton-like system. Research shows that when the pH is 2-5, the dosage of Fe3O4-MnO2-PAC is 800mg/L, the dosage of H2O2 is 0.8mol/L, the reaction temperature is 10°C-50°C, Fe3O4-MnO2-PAC catalyst. When used less than five times, it has a better degradation effect on methylene blue wastewater.

Research application coal material is prepared from maccadamia peel and denatured by H2O2 to treat methylene blue

Macadamia shell contains a carbon content (47 - 49%), in addition, the shell contains 46.52% Oxidation, Hidro 6.10%, Nitrogen 0.36% and relatively low ash content of only 0.22%, this indicates the grain Macadamia has the potential to become activated carbon thanks to the above characteristics. This study was conducted to modify activated carbon by oxidizing agents to change the surface structure of activated carbon from hydrophobic to hydrophilic, non-polarizing to polarization, increasing the amount of adsorption simultaneously creating more durable links between dyes and activated carbon. Study of Methylene Blue wastewater treatment with coal from Maccadamia shell modified with H2O2 agent at H2O2 ratio : coal = 10:1. Research results show that Methylene Blue adsorption capacity reaches 1g /266,26mg Methylene Blue at optimal conditions corresponding to 25% concentration and 48 hours of soaking time. Analysis of infrared spectra showed that coal is modified by H2O2 agent with functional groups –OH, Carboxylic functional group C=O, group C-H in NH3, C–N group in Amine aliphatic or in Alcohol or Phenol and C–O bonding. Modified coal by H2O2 oxidation agent has Methylene Blue color treatment efficiency of 93.26%, corresponding to the original color of 474.67 Pt - Co at the respective optimal conditions pH = 8.5, dose of 1 g/L and treatment time of 60 minutes. Research results are similar to other research results and are applicable to color wastewater treatment.

Study on Influencing Factors of Adsorption of Methylene Blue on Magnetic Graphene Oxide Composite

In order to explore the optimal reaction conditions of magnetic graphene oxide composite materials for the treatment of methylene blue wastewater. By controlling the pH value, contact time, temperature, the amount of adsorbent added for comparative analysis, and finally determine the best operating conditions. The study showed that when the pH value was 7, the contact time was 1440 min, the reaction temperature was 25 ° C, and the dosage of the adsorbent was 0.5 g / L, the treatment effect was the best. Parameter optimization can effectively improve the processing effect.

Application of Natural Zeolite in Methylene Blue Wastewater Treatment Process by Adsorption Method

Textile industry waste contains dyes that are difficult to decompose naturally and cause disruption of ecosystems in water. The colorant that is often used in the textile industry is methylene blue which is a cationic heterocyclic aromatic compound. This compound is so stable that it is difficult to decompose naturally and is harmful to the environment in large concentrations. Therefore, we need a waste treatment technology that can reduce the concentration of dye waste in water. So far, the adsorption method remains the most efficient and effective technique in removing dyes because of its relatively large adsorption capacity. One method that can be used is the adsorption method using natural zeolite. Zeolite is one of the non-metal mineral commodities or multipurpose industrial minerals, one of which is as an adsorbent or adsorbent media. This study aims to determine the potential of natural zeolite in absorbing methylene blue with variations in the concentration of methylene blue and various sizes of natural zeolite mesh. The procedures in this experiment include, the preparation of natural zeolite with size variations of 20-60 mesh, 60-100 mesh and> 100 mesh and variations in the concentration of methylene blue used 15 ppm, 30 ppm and 45 ppm with contact time from 0 to 180 minutes. From the results of the study it was found that the smaller the size of natural zeolite used, the greater the percentage of dye removal that is at mesh size> 100 mesh the percentage of dye removal was 32.11%. As for the variation of the concentration of methylene blue, the smaller the concentration, the natural zeolite can work optimally ie at a concentration of 15 ppm at 180 minutes the remaining methylene blue concentration of 0.145 ppm.

Preparation of Adsorbent from Fly Ash for Methylene Blue Wastewater Treatment

Fly ash contains SiO2 and Al2O3, which account for more than 60% of the total. This is similar to the composition of zeolite which is frequently be used for adsorbent. Therefore, fly ash is used to prepare adsorbent for wastewater treatment by microwave-assisted hydrothermal method. The optimal reaction conditions were determined: alkali-ash ratio of 15:1, reaction temperature of 100°C and reaction time of 0.5h. The removal rate of methylene blue is up to 97.6%. The adsorbent was characterized by SEM and FT-IR. Large number of silicon (aluminum) oxygen tetrahedrons and the porous lattice structure contribute high adsorption performance of the adsorbent.

Citrus Pectin-Derived Carbon Microspheres with Superior Adsorption Ability for Methylene Blue.

In this study, citrus pectin-derived, green, and tunable carbon microspheres with superior adsorption capacity and high adsorption rate, as well as good reusability toward methylene blue adsorption, were prepared by a facile hydrothermal method without any hazardous chemicals. The materials hold great potential for the treatment of methylene blue wastewater.

Degradation of methylene blue in a heterogeneous Fenton reaction catalyzed by chitosan crosslinked ferrous complex

A novel heterogeneous Fenton chitosan-Fe catalyst (CS-Fe), the ferrous ions coordinated by amino and hydroxyl groups of CS, was prepared and characterized by FT-IR and XRD. The decolorization of methylene blue (MB) was monitored by UV–vis spectra and chemical oxygen demand (COD). At the optimum reaction conditions, 10000mgl−1 CS-Fe, 1200mgl−1 H2O2, 30°C, original pH, 120mgl−1MB, up to 99% color removal for MB was achieved at 30min, superior to other Fenton systems. The study of COD removal and UV–vis spectra suggested that the uncompletely mineralization of MB occurs in the CS-Fe system. The concentration of Fe iron dissolved from CS-Fe was negligible relative to CS-Fe applied and the removal of MB remains as high as 90% after recycled five times, indicating that this novel heterogeneous Fenton catalyst is efficient for MB wastewater treatment. Moreover, almost 90% of color removal obtained after five cycles and low amount of dissolved iron were detected in solution, indicating that the catalyst has good stability.

A New Ferric Chloride Modified Kaolin Coagulant and Its Application in Treatment of Methylene Blue Wastewater

A New Ferric Chloride Modified Kaolin Coagulant and Its Application in Treatment of Methylene Blue Wastewater

Adsorptive removal of methylene blue by rhamnolipid-functionalized graphene oxide from wastewater

In this article, a rhamnolipid-functionalized graphene oxide (RL-GO) hybrid was prepared by one-step ultrasonication and adsorptive removal of methylene blue (MB) from both artificial and real wastewater by the RL-GO was investigated. The Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Fourier transform infrared spectrum (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) area and Zeta potential analysis were used to characterize the adsorbent. The results showed that RL-GO had abundant functional groups and a mesopores feature. MB adsorption by the RL-GO increased with increase in adsorbent dose, pH, temperature and initial MB concentration, while it was insensitive to ionic strength variation. The adsorption kinetics fitted well to the pseudo-second-order model with correlation coefficients greater than 0.999. The Intra-particle diffusion and Boyd's film-diffusion models showed that the rate-controlled step was dominated by film-diffusion in the beginning and then followed by intra-particle diffusion. The adsorption isotherm was fitted by adsorption models with the suitability in order of BET > Freundlich > Langmuir > Temkin, based on comparison between correlation coefficients. Thermodynamic analysis of equilibriums suggested that the adsorption MB on RL-GO was spontaneous and endothermic. The adsorption mechanism was also proposed to be electrostatic attraction, π–π interaction and hydrogen bond. In addition, the real wastewater experiment, the regeneration study and the comparative cost analysis showed that the RL-GO composites could be a cost-effective and promising sorbent for MB wastewater treatment owing to its high efficiency and excellent reusability.

Effective ultrasound electrochemical degradation of methylene blue wastewater using a nanocoated electrode

A novel sonoelectrochemical catalytic oxidation-driven process using a nanocoated electrode to treat methylene blue (MB) wastewater was developed. The nano-scale (nanocoated) electrode generated more hydroxyl radicals than non-nano-scale (non-nanocoated) electrodes did. However, hydroxyl radicals were easily adsorbed by the nanomaterial and thus were not able to enter the solution. Supersonic waves were found to enhance the mass-transfer effect on the nanocoated electrode surface, resulting in rapid diffusion of the generated hydroxyl radicals into the solution. In solution, the hydroxyl radicals then reacted with organic pollutants in the presence of ultrasonic waves. The effect of the nanocoated electrode on the MB wastewater treatment process was enhanced by ultrasound when compared to the non-nanocoated electrode used under the same conditions. The synergy of the nanocoated electrode and ultrasonic waves towards MB degradation was then studied. The optimum operating conditions resulted in a 92% removal efficiency for TOC and consisted of a current of 600mA, an ultrasound frequency of 45kHz, and a supersonic power of 250W. The mechanism of ultrasound enhancement of the nanocoated electrode activity with respect to MB treatment is discussed. The reaction intermediates of the sonoelectrochemical catalytic oxidation process were monitored, and degradation pathways were proposed. The sonoelectrochemical catalytic oxidation-driven process using nanocoated electrodes was found to be a very efficient method for the treatment of non-biodegradable wastewater.

Preparation and characterization of NZVI–MCM-48 mesoporous molecular sieves and its mechanism for treatment of methylene blue wastewater

The nanoscale zero valent iron (NZVI) and ordered mesoporous molecular sieve Mobil Composition of Matter No. 48 (MCM-48) composite material (NZVI–MCM-48) were prepared by the hydrothermal treatment at 120°C for 36 h and then drying at 100°C of synthetic solution with a mole ratio of silica, cobalt, cetyltrimethylammonium bromide (CTAB), sodium hydroxide, sodium fluoride, and water is l:0.01:0.65:0.5:0.1:71 to get the NZVI–MCM-48 raw powder which was then treated by roasting in a nitrogen atmosphere to release the surfactant and by high temperature carbonization and reduction. The existence of NZVI in the composite material and its orderliness, form, and element composition were analyzed by characterization means such as X-ray diffractometer (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and energy dispersive spectrometer (EDS). The orthogonal degradation experiment for treating methylene blue (MB) wastewater by the composite material led to a 853 mg/g decolorization rate of MB and a 821 mg/g chemical oxygen demand (COD) removal rate under the optimal conditions including an initial concentration of wastewater of 10 mg/L, an initial pH of 6, a concentration of the added sample of 0.8 g/L, and a reaction time of 60 min. The degradation mechanism for MB wastewater is also discussed.

Electrochemical Treatment of Simulated Dye Wastewater

The Ti/SnO2-Sb2O3/PbO2 electrodes were prepared by thermal decomposition method and its application in the electrochemical degradation of a heteropolyaromatic dye, Methylene blue (MB), contained in simulated dye wastewater were investigated under mild conditions. The effects of pH, current density and electrolysis time on de-colorization efficiency were also studied. Chemical oxygen demand (COD) was selected as another parameter to evaluate the efficiency of this degradation method on treatment of MB wastewater. The results revealed that when initial pH was 6.0, current density was 50 mA·cm2, electrolysis time was 60 min, Na2SO4 as electrolyte and its concentration was 3.0 g·dm3, the de-colorization and COD removal efficiency can reach 89.9% and 71.7%, respectively.

Electro-catalytic degradation of methylene blue wastewater assisted by Fe 2O 3-modified kaolin

The electrochemical oxidation of methylene blue (MB) wastewater assisted by Fe 2O 3-modified kaolin in a 200 mL electrolytic batch reactor with graphite plate as electrodes was investigated. The catalyst was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effects of pH, current density and introduction of NaCl on the efficiency of the electrochemical degradation process were also studied. It was found that Fe 2O 3-modified kaolin has higher catalytic activity in the electrochemical degradation of MB wastewater. 96.47% chemical oxygen demand (COD) removal was obtained in 40 min of electrochemical treatment of MB wastewater at pH 3, current density was equal to 69.23 mA cm −2.