Maximum Dye Removal Efficiency Research Articles

Removal of brilliant green dye from aqueous solution by electrocoagulation using response surface methodology

This study proposed batch electrocoagulation with iron electrodes as a simple and economical method for treating aqueous solution containing 250 mg/l of brilliant green dye. Response surface methodology was performed to design experiments and to optimize the process. A total of 20 experiments were conducted to study the effect of three important process parameters: initial solution pH (5–11), current density (5–20 mA/cm2) and reaction time (10–40 min). Multiple response optimization reveals that a maximum dye removal efficiency of 96.1% with minimum electrical energy consumption of 3.857 kW h/kg dye removed was achieved at optimum conditions.

Removal of Acid Violet 49 and Acid Red 88 dyes from Aqueous Solutions using Advanced Oxidation Process

Dyes used in various industries are stable, difficult to degrade and carcinogenic in nature. Discharge of effluents containing unexhausted dyes affect aquatic and human chain. Treatment of effluents hence gains utmost priority before its disposal into water streams. In the present study, removal of two acid dyes: Acid Violet 49 (AV49) and Acid Red 88 (AR88) from aqueous solutions using Fenton’s process are conducted. Factors influencing dyes removal efficiency were investigated. It was observed that maximum AV49 dye removal efficiency of 98.35% was achieved when solution pH, H2O2, and Fe2+ were 3, 0.005 mol, and 0.0005 mol, respectively for 100 mg/L dye solution. Whereas for 200 mg/L AV49 dye, the maximum dye removal efficiency of 97.25% was obtained with solution pH, H2O2, and Fe2+ were 3, 0.01 mol, and 0.001 mol, respectively. The optimum conditions for 100 mg/L AR88 dye were: solution pH = 3, H2O2 = 0.006 mol, Fe2+ = 0.0005 mol, and dye removal efficiency, 97.30%. Similarly, for 200 mg/L, the dye removal efficiency of 96.50% was achieved with solution pH = 3, H2O2 = 0.012 mol, and Fe2+ = 0.001 mol. This study showed high removal efficiency of AV49 and AR88 from aqueous solutions using Fenton’s reagents

Adsorption of crystal violet dye by a zeolite-montmorillonite nano-adsorbent: modelling, kinetic and equilibrium studies

AbstractA zeolite-montmorillonite (zeolite-Mt) nano-adsorbent was prepared by calcination at 600°C. The synthesized nano-adsorbent was tested for removal of a toxic and cationic dye (crystal violet) from water, and it was characterized by various techniques. The effects of variables such as pH, temperature, adsorbent dosage and initial dye concentration on the removal efficiency of the dye were investigated by response surface methodology (RSM). Experimental conditions were optimized by RSM to achieve the maximum dye removal efficiency. Optimum conditions for maximum removal of dye were obtained at pH 9, temperature of 25°C, adsorbent dosage of 2 g L−1 and initial dye concentration of 40 mg L−1. Under these conditions, the maximum removal efficiency obtained was 99.9%. Various isotherms were applied to study adsorption equilibrium, and of these, the Freundlich isotherm provided the best fit. In addition, the fractal-like integrated kinetic Langmuir model was the most appropriate among several kinetic models. The thermodynamic parameters were also determined. The zeolite-Mt prepared under optimum conditions displayed a greater adsorption capacity than activated carbon (manufactured by Merck) and than various other adsorbents.

Removal of Direct Blue-86 dye from aqueous solution using alginate encapsulated activated carbon (PnsAC-alginate) prepared from waste peanut shell

The alginate encapsulated activated carbon (PnsAC-alginate), prepared from waste peanut shell was used as an adsorbent for the removal of Direct Blue-86 (DB-86) from aqueous solutions. The effects of temperature, extraction time, adsorbent dose, dye concentration and solution pH on the adsorption of DB-86 onto PnsAC-alginate were studied. Central composite design coupled with response surface methodology (RSM) was used to optimize the adsorption feed conditions in order to achieve maximum dye removal efficiency. The statistical analysis revealed that for maximum dye removal efficiency, the optimal conditions were adsorbent dose of 24.65 g L−1, DB-86 dye concentration of 125.5 mg L−1 and pH of 3.1. Under the optimized conditions, experimental dye removal efficiency (98.4 ± 0.1%) agreed closely with the predicted results, indicating the suitability of RSM in optimizing the feed conditions. SEM-EDX, TEM, XRD, BET, and FTIR analyses showed the surface morphology of the adsorbents and confirmed the adsorption of DB-86 onto PnsAC-alginate. The experimental results revealed about 7% enhancement of dye removal efficiency compared to that with unmodified PnsAC adsorbent. The adsorption kinetics of DB-86 was well described by Pseudo second order kinetic model with intra-particle and film diffusion mechanisms. Langmuir isotherm model provided the best fit to the adsorption equilibrium data, obtaining maximum dye adsorption capacity of 21.6 ± 0.9 mg g−1. Estimation of thermodynamic parameters revealed that adsorption process was feasible with spontaneous and endothermic in nature. The present study demonstrated that use of PnsAC-alginate adsorbent might be cost effective and suitable alternative for removal of DB-86 dye from aqueous solutions.

Removal of Acid Orange 7 dye from aqueous solutions using polyaniline-modified rice bran: isotherms, kinetics, and thermodynamics

Background: Today, due to increasing usage of dyes in various industrials and their destructive effects on health and environment, it is necessary to remove them from industrial wastes. Although there are few studies on the use of rice bran modified with polyaniline (RB/PANI) for removal of different dyes, but the effect of this adsorbent on the removal of Acid Orange 7 (AO7) dye has not been evaluated yet. Therefore, this study was conducted to investigate the removal of AO7 dye by RB/PANI as an adsorbent. Methods: The adsorbent characteristics were determined using scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Also, the adsorbent surface area was measured by Brunauer–Emmett–Teller (BET) technique. The method of one-factor-at-a-time was used to optimize various factors including pH, temperature, and adsorbent dosage. Results: The optimal values for the factors affecting AO7 dye removal were calculated. It was revealed that the maximum dye removal was obtained at pH = 3, temperature = 25˚C, dye concentration = 30 mg/L, adsorbent dosage = 30 mg/L, and contact time= 60 minutes. The maximum removal percentage for RB/PANI was 97.13%. It was also revealed that Langmuir isotherm is the best fitted isotherm model. Conclusion: According to the results, the polyaniline-modified rice bran could be used as an excellent adsorbent for the removal of AO7 from aqueous solutions. The maximum dye removal efficiency for AO7 was obtained at pH = 3. Also, it was revealed that AO7 dye removal follows the pseudo-secondorder kinetic model and it is a spontaneous process.

Development of carbon dot-modified polyethersulfone membranes for enhancement of nanofiltration, permeation and antifouling performance

A novel mixed matrix nanofiltration membrane was developed by blending carbon dots (CDs) into a polyethersulfone (PES) matrix. The resulted membranes were characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflection (ATR), zeta potential, tensile strength, overall porosity, and water contact angle tests. Pure water flux, antifouling, as well as salt and dye rejection properties were also studied. Fouling resistance of the prepared nanocomposite membranes was tested with filtration of a bovine serum albumin (BSA) solution. The calculated roughness parameters showed that addition of CDs can effectively reduce the roughness value of the PES membrane. The membrane permeability raised to the maximum value of 76.5 kg/m2 h, which is almost twice the bare PES, by step-wise increasing of the CDs dosage from 0.05 to 0.50 wt%. The 0.50 wt% PES/CDs membrane also showed significant antifouling properties, with the total and irreversible fouling values of 35.6 and 20.3%, respectively, compared to the values of 54.7 and 46.3%, in case of the bare PES. Salt rejection was remarkably improved after addition of CDs with the sequence of Na2SO4 > MgSO4 > NaCl, after 90 min of filtration. The dye rejection was near total removal with above 97% in all prepared membranes, where the maximum dye removal efficiency (98.9%) was observed for the 0.50 wt% PES/CDs, introducing CDs as an excellent membrane modifier for wastewater treatment applications.

Hydrothermal Synthesis of N-Doped GQD/CuO and N-Doped GQD/ZnO Nanophotocatalysts for MB Dye Removal Under Visible Light Irradiation: Evaluation of a New Procedure to Produce N-Doped GQD/ZnO

During the last decade, dye pollution has been a major environmental concern, making it necessary to develop removal methods. In this study, three nanophotocatalysts, namely ZnO, CuO, and ZnO/CuO composite, were synthesized via a hydrothermal method and then examined for degradation of methylene blue (MB) dye solution under visible light irradiation. Pure ZnO and CuO showed rather poor photocatalytic activities due to their limited photo response ranges under visible light. Accordingly, in order to overcome this limitation and improve the photocatalytic activity of ZnO and CuO, nitrogen-doped graphene quantum dots (N-GQDs) were employed. Results proved that the N-GQDs can significantly enhance photocatalytic activity of the ZnO sample, while no significant effect was observed on CuO sample. Furthermore, effects of synthesis method and added content of N-GQDs on the activity of the N-GQDs/ZnO composite samples were studied. Firstly, pure ZnO was synthesized via a hydrothermal reaction and then added to the N-GQDs precursor solution to produce N-GQD/ZnO composite in a final hydrothermal reaction (method I). Alternatively, a hydrothermal method was used to prepare the N-GQDs firstly, and then zinc acetate was introduced into this solution for final hydrothermal process (method II). The results showed higher elimination performance of the second method, by which the MB dye could be removed completely. The best nanophotocatalyst (the sample containing 3 mmol of ascorbic acid in the primary solution, prepared via the second method) demonstrated maximum dye removal efficiency (70% in about 30 min, 100% < 60 min). Thus, nanophotocatalysts of similar characteristics are suggested for industrial effluent purification under visible light.

Comparison of Drying Method on Acid-functionalized Multi-walled Carbon Nanotube and their Application for Dye Removal

The application of surface modified multi-walled carbon nanotube is one of the emerging adsorbents for removal of pollutants from wastewater, particularly dye pollutants. In this study, the effects of drying methods on acid functionalized MWCNT (f-MWCNT) by using freeze dry or oven dry treatment methods were investigated and compared. It is vital to have a proper drying method in order to attain desired particles sizes and properties. Freeze-dried MWCNT (FD-MWCNT) were more desirable than oven-dried MWCNT (OD-MWCNT), as they were in soft flake form, with no formation of aggregates. Besides, characterization studies were performed to analyze the surface morphology and chemical compositions of the f-MWCNTs. Results revealed that FD-MWCNT has less structural damaged and higher oxygenated functional groups than OD-MWCNT. As for batch dye adsorption experiments, FD-MWCNT has higher performances compared to OD-MWCNT. The maximum dye removal efficiency that FD-MWCNT can achieve was 99% at pH 7, 90 min, 10 mg/L dye initial concentration and 150 rpm. It has been proved that freeze dry treatment is more favorable than oven dry method as the dried MWCNT obtained has superior structure properties and adsorption capability for dye removal.

Removal of methylene blue by electrocoagulation: a study of the effect of operational parameters and mechanism

Electrocoagulation has become an attractive approach to remove organic dye pollutants from wastewater in recent years. The current study investigated the removal of methylene blue by the electrocoagulation method using aluminum electrodes. The effects of the operating parameters, such as electrolysis time, initial solution pH value, initial dye concentration, and electrolyte dosage were investigated to optimize the operating conditions for maximum benefits. The findings in this study revealed that an increase in the electrolysis time up to 5–30 min enhanced the color removal efficiency, from a dye solution in the pH range of 3 to 11. The experimental results showed that the electrocoagulation method is significantly efficient in the removal of methylene blue. The maximum dye removal efficiency achieved was 99.37% under the following operating conditions: current density of 5 mA/cm2, electrolysis time of 30 min, initial solution pH value of 7, and sodium chloride concentration of 0.2 mol/L. The methylene blue removal mechanism was studied by Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy.

Removal of Dyes from Synthetic Waste Water by Coagulation Technique Using Natural Coagulants

The adsorption performances of polymer coagulants were studied for color removal from the aqueous dye solution. The coagulation behavior of Naphthalene black and Alizarin red dye from synthetic waste water onto the tiger nut powder and alum was investigated using initial concentration, solution pH, contact time, coagulant dosage, and temperature and particle size. The percentage color removal for the two dye solutions were found and compared with that of alum and the result of the study showed that increase in dye initial concentration from 50mg/L to 500mg/L at room temperature with tiger nut decreased the removal efficiency from 63.74% to 34.9% for naphthalene black and alizarin red from 70.12% to 42.00%. Also, for dye concentration above 100mg/L with alum, the removal efficiency of both dyes started decreasing from 59.22 to 27.34% for naphthalene black and from 62.46 to 33.50% for alizarin red. The maximum dye removal efficiency occurred at a pH of 2 for both naphthalene and alizarin red with tiger nut but occurred at pH of 5 for both dyes with alum. Coagulant dosage from 100 to 1000mg/l with tiger nut increased the removal efficiency of naphthalene black and alizarin red from 44.08% to 94.43%; and 50.10% to 96.55 respectively while with alum it increased from 25.18% to 67.90% for naphthalene black and 35.74% to 78.89% for alizarin red. The reaction kinetics of Naphthalene black and Alizarin red was observed to obey Pseudo second-order kinetics with rate constants K2of 2.4691g/mg minutes and 2.7579g/mg min, respectively. From result, it is evident that tiger nut is a better low cost natural coagulant effective for the removal of dye from synthetic waste water. However, the removal efficiency is higher in Alizarin red than in Naphthalene black at the same concentration under the same condition.

Iron impregnated biochars as heterogeneous Fenton catalyst for the degradation of acid red 1 dye

In the present work, Acid Red 1 (AR1) dye degradation by two heterogeneous Fenton catalysts, namely iron loaded rice husk biochar (Fe-RHB) and coir pith biochar (Fe-CPB) are studied. Biochar prepared from RHB and CPB were sonicated in the presence of ferric nitrate for the synthesis of Fe-RHB and Fe-CPB by incipient impregnation method. Effect of operational parameters such as pH, the dosage of catalyst, H2O2 concentration and temperature were examined. Characterization of the synthesized Fenton catalyst, Fe-RHB and Fe-CPB were analysed by SEM, EDS, XRD and XPS techniques. In Fe-RHB Fenton system, maximum dye removal efficiency of 97.6% and TOC removal efficiency of 84.2% were obtained at pH 3 for 50 mg L−1 of AR1 concentration, with 16 mM of H2O2 and 5 g L−1 of catalyst dosage within 120 min reaction time. Similarly, for Fe-CPB, maximum dye removal efficiency of 99.1% and TOC removal efficiency of 86.7% were obtained with 16 mM of H2O2 and 4 g L−1 of dosage for 50 mg L−1 of initial dye concentration at pH 3. The prepared catalysts can be reused for successive cycles as the catalyst materials are highly stable and have very less iron leaching property.

A novel carboxyl-rich chitosan-based polymer and its application for clay flocculation and cationic dye removal

Due to the complexity of contaminants, the effectiveness of traditional flocculants toward water purification is insufficient. To break the limitation, a novel polymer flocculant [chitosan grafted poly (acrylamide-itaconic acid), CS-g-P(AM-IA)] was synthesized via ultraviolet-initiated graft copolymerization reaction. Characterization results revealed that the graft copolymers were successfully synthesized and with rougher surface structure. The solubility of CS-g-P(AM-IA) and chitosan grafted polyacrylamide (CS-g-PAM) were greatly improved and they can dissolve in the wide pH range of 2.0–12.0. CaCl2 was used as a source of cation bridge to enhance the flocculation of kaolin particles, and its optimum dosage was 150 mg·L−1. At dosage of 30 mg·L−1 and pH of 5.0, the turbidity removal efficiency of CS-g-P(AM-IA) reached the maximum of 93.8%, whereas those of CS-g-PAM and CS were 96.7% and 76.9%, respectively. The patchwise adsorption of ionic groups embedded in the molecular chain on Ca2+-clay complexes took effect to generate flocs with larger particle size. Besides, the decolorization ability of cationic dyes by CS-g-P(AM-IA) was greatly enhanced due to the role of abundant carboxyl groups. In the crystal violet (CV) adsorption experiment, the maximum CV dye removal efficiency for CS-g-P(AM-IA) reached the maximum of 81.6% at dosage of 0.7 mg·mL−1 and pH of 9.0, while those for CS-g-PAM and CS were 51.7% and 36.5%, respectively.

Adsorption of Remazol Brillant Green 6B (RBG 6B) on chitin: process optimization using response surface methodology

In the present study, the adsorption of Remazol Brillant Green 6B (RBG 6B) on chitin which characterized by BET, FTIR, XRD and SEM analysis was studied. Response surface methodology (RSM) was applied to determine interaction between solution pH, initial RBG 6B concentration and chitin dosage being individual variables and to optimize operating conditions. According to results of variance analysis (ANOVA), the second order polynomial model was statistically significant (P&lt;0.0001) and coefficient of determination value (R2=0.98) was high. It was determined that dye removal efficiency increased when low solution pH and initial RBG 6B dye concentration and high chitin dosage were used. The maximum dye removal efficiency was obtained as 88% at solution pH of 3.0, initial RBG 6B concentration of 75 mg L-1 and chitin dosage of 5.0 g L-1. The isotherms and kinetics studies showed that Freundlich isotherm and pseudo-second-order kinetics model fitted well to the RBG 6B adsorption data.

Synthesis of Magnetic Nanocomposite Core–Shell Fe3O4@MCM-41-NH2 and its Application for Removal of Congo Red from Aqueous Solutions

A core–shell Fe3O4@MCM-41-NH2 was synthesized as a magnetic mesoporous nanocomposite was used as an adsorbent for the effective and rapid removal of anionic dye, Congo red. The Fe3O4@MCM-41-NH2 nanocomposites were characterized by FT-IR, SEM, TEM and XRD. The selected removal conditions obtained by a central composite design under response surface methodology were: pH 4.0, mass of adsorbent 0.01 g, stirring time 2.84 min and dye concentration 15 mg L−1. Under these conditions maximum dye removal efficiency obtained was about 95.12%. The adsorption isotherms at different temperatures were fitted well with Langmuir model. Various kinetics models were examined and the results showed that pseudo-second-order could be the best model for the adsorption rate.

A novel photocatalytic self-cleaning PES nanofiltration membrane incorporating triple metal-nonmetal doped TiO2 (K-B-N-TiO2) for post treatment of biologically treated palm oil mill effluent

Biologically treated palm oil mill effluent (POME) still has a dark-brown color and contains residual organic matter. In this paper, a novel self-cleaning mixed matrix K-B-N triple doped-TiO2/PES nanofiltration membrane at three weight fractions (0.1, 0.5 and 1 wt%) was prepared by the phase inversion method. The performance of the prepared membranes was investigated in terms of permeability, fouling resistance and capability for post treatment of the biologically treated POME. The prepared membranes were characterized by contact angle measurement, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The obtained results indicated that the pure water flux of the modified membranes improved significantly by addition of K-B-N-TiO2 nanoparticles up to 0.5 wt% which could be attributed to the hydrophilic nature of the nanoparticles and induced photocatalytic ability. Also, flux recovery ratio (FRR) of the optimized membrane was increased from 48 to 95.4% relative to unfilled membrane that confirmed antifouling and self-cleaning capability of the nanocomposite. This behavior was ascribed to the photocatalytic role of the nanoparticles resulting mineralization of organic matter from surface of the modified membrane that enhanced reusability of the prepared membranes. Maximum permeation flux, dye and COD removal efficiencies were obtained about 27 kg/m2 h, 98% and 90%, respectively for treating the biologically treated POME.

Sonochemical synthesis of highly crystalline photocatalyst for industrial applications

Highly photo active pure anatase form of TiO2 nanoparticles with average particle size 4nm have been successfully synthesized by ultrasonic acoustic method (UAM). The effects of process variables i.e. precursors concentration and sonication time were investigated based on central composite design and response surface methodology. The characteristics of the resulting nanoparticles (RNP) were analyzed by scanning electron microscopy, dynamic light scattering, transmission electron microscopy, X-ray diffractometry and Raman spectroscopy. Photocatalytic experiments were performed with methylene blue dye which is considered as model organic pollutant in textile industry. A comparative analysis between the RNP and commercially available Degussa P25 for photocatalytic performance against dye removal efficiency was performed. The rapid removal of methylene blue in case of RNP indicates their higher photocatalytic activity than P25. Maximum dye removal efficiency 98.45% was achieved with optimal conditions i.e. TTIP conc. 10mL, EG conc. 4mL and sonication time 1h. Interestingly, no significant difference was found in the photocatalytic performance of RNP after calcination. Moreover, self-cleaning efficiency of RNP deposited on cotton was evaluated in RGB color space. The obtained results indicate the significant impact of ultrasonic irradiations on the photocatalytic performance of pure anatase form than any other hybrid type of TiO2 nanoparticles.

Adsorption Kinects and Isotherms for Removal of Rhodamine B (dye) using Adsorbents prepared from drinking water treatment sludge

The present work aims to investigate the removal of Rhodamine B dye (RB) from aqueous solution by using adsorbents prepared from alum sludge (AS) and Mud sludge (MS) of drinking water treatment plant. The effect of dye concentration, contact time, pH, temperature and adsorbent dose on the dye removal was studied. The equilibrium adsorption data of RB dye on the developed adsorbents were analyzed by the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) Isotherms. The sorption data fitted well to Langmuir isotherm model. The maximum dye removal efficiency was observed at pH 7, contact time 90 min,and 0.1-0.25 gm dosage for both (AS) and (MS) adsorbents . Also, four kinetic models such as Pseudo-first order, Pseudo-second order, Intraparticle diffusion and Elovich models were tested to interpret the experimental data. The kinetic experimental data were fitted well to Pseudo-second order model.The thermodynamics parameters of adsorption system indicated spontaneous and endothermic process. Results indicate the effectiveness of the developed adsorbents for removing RB dye.

Environmental Application of Telon Blue AGLF Adsorption on Sunflower Pulp: A Response Surface Methodology Approach and Kinetic Study

The adsorptive removal of Telon Blue AGLF (TB AGLF) from aqueous solution using sunflower pulp was studied. The effects of pH, adsorbent dose, temperature, and initial dye concentration on the adsorption capacity and the removal % of TB AGLF were investigated. Experimental results showed that sunflower pulp was excellent agroindustrial adsorbent with maximum dye removal efficiency of 97.22% for a very short time (under conditions of 100 mg L−1initial dye concentration, pH = 3,T=50°C, and 1 g L−1of adsorbent dose). The binary effects of initial dye concentration and temperature on the adsorption properties of sunflower pulp were analysed by RSM and two model equations for predicting adsorption capacity and dye removal % of pulp because arbitrarily chosen initial dye concentration and temperature were developed by using response surface methodology (RSM). Experimental values of the adsorption capacity and dye removal % were in good agreement with the predicted values by the improved models. Adsorption experiments and kinetic regression results indicated that the experimental data were well defined with pseudo-second-order kinetic model.

Biosorption of malachite green dye from aqueous solution by calcium alginate nanoparticles: Equilibrium study

Alginates, in the form of beads and hydrogels have been widely investigated for their effectiveness in pollutant removal from aqueous solution. Nanoparticles with the advantage of greater surface area and ease of mixing with contaminated water are more effective in water purification and are not much investigated. Here the dye removal potential of calcium cross-linked alginate nanoparticles, prepared by green method, is investigated in batch adsorption technique. Effect of system variables such as pH, initial dye concentration, contact time, temperature and adsorbent dose on sorption process was studied. The synthesized nanoparticles exhibited a maximum dye removal efficiency of 98.5% at 60°C and at pH10 in 5min contact time. The experimental data fitted well with Langmuir model indicating monolayer adsorption mechanism and the sorption process obeyed pseudo second order kinetics. The rate-limiting mechanism in the biosorption of the dye involves a combination of intraparticle diffusion and surface adsorption. The investigation of thermodynamic parameters such as ∆G0, ∆H0 and ∆S0 confirmed the spontaneity, randomness and endothermic nature of the biosorption process. This study demonstrates that calcium alginate nanoparticles are promising biosorbent for the removal of dyes from aqueous solution as exemplified by malachite green.

Synthesis of nanoporous Zn-WO3 by microwave irradiation method for photocatalytic applications

Nanoporous Zn-WO3 was successfully synthesized by microwave irradiation method. The surface characterization of Zn-WO3 was carried out using X-ray diffraction spectroscopy (XRD), Raman spectra and scanning electron microscopy (SEM). XRD shows the formation of orthorhombic structured WO3 and Zn doped WO3 materials. SEM images reveal the nanosphere and nanoporous morphologies of WO3 and Zn-WO3. It has been found that the pH of the starting precursor solution influences the physical and chemical properties of the synthesized nanomaterials. The synthesized nanoporous Zn-WO3 successfully decomposed the methylene blue under UV light irradiation. The effects of Zn-WO3 dose and irradiation time for photodegradation of dye were also studied. The maximum dye removal efficiency of 91.7 % was achieved.