Application of MnO2 Materials to Dye Removal from Aqueous Solution by Adsorption

2013 ◽  
Vol 361-363 ◽  
pp. 760-763 ◽  
Author(s):  
Wei Fang Dong ◽  
Li Hua Zang ◽  
Hao Li
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Adsorption Capacity ◽  
Contact Time ◽  
Dye Removal ◽  
Good Alternative ◽  
Order Kinetic ◽  
Dye Wastewater ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The adsorption capacity was compared for the dye wastewater onto adsorbent MnO2. The effects of contact time and dosage of adsorbent were studied. The adsorption kinetics was analyzed. The results showed that MnO2 possessed higher adsorption capacity to Methylene blue than Methyl orange which the removal efficiency could reached 94.82%and 78.63% respectively under the conditions (the dosage1.2g/L, time 60min, initial dye concentration 50mg/L, pH7). The dynamical data fit well with the pseudo second order kinetic model. The MnO2 has higher Methylene blue adsorption capacity in short equilibrium times and are good alternative in wastewater treatment.

scholarly journals Study on the adsorption of methylene blue from aqueous solution using hydrogel glucomannan/graphene oxide

2021 ◽  
Vol 10 (1) ◽  
pp. 59-66
Author(s):  
Son Le Lam ◽  
Phu Nguyen Vinh ◽  
Hieu Le Trung ◽  
Tan Le Thua ◽  
Nhan Dang Thi Thanh ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Graphene Oxide ◽  
Adsorption Capacity ◽  
Organic Dyes ◽  
Dye Adsorption ◽  
Order Kinetic ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Glucomannan/graphene oxide (GM/GO) hydrogel was synthesized by using calcium hydroxide as the crosslinker. The synthesized material was characterized by using IR, XRD, SEM, EDX and RAMAN technology. The composite hydrogel was used for removal of organic dyes from aqueous solution. The results showed that the GM/GO hydrogel had a porous structure and a high adsorption capacity toward methylene blue (MB). The pseudo-second-order kinetic model could fit the rate equation of MB adsorption onto the GM/GO hydrogel. The adsorption of MB onto GM/GO hydrogel was a spontaneous process. In addition, the equilibrium adsorption isotherm data indicated that equilibrium data were fitted to the Langmuir isotherm and the maximum dye adsorption capacity was 198,69 mg.g-1. Moreover, the hydrogel was stable and easily recovered and adsorption capacity was around 97% of the initial saturation adsorption capacity after being used five times.

scholarly journals Biosorption of Congo Red and Methylene Blue by pretreated waste Streptomyces fradiae biomass - Equilibrium, kinetic and thermodynamic studies

2018 ◽  
Vol 83 (1) ◽  
pp. 107-120 ◽  
Author(s):  
Zdravka Velkova ◽  
Gergana Kirova ◽  
Margarita Stoytcheva ◽  
Velizar Gochev
Keyword(s):  
Methylene Blue ◽  
Congo Red ◽  
Contact Time ◽  
Order Kinetic ◽  
Batch Experiments ◽  
Streptomyces Fradiae ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Kinetic And Thermodynamic Studies ◽  
Pretreated Biomass

Pretreated waste Streptomyces fradiae biomass was utilized as an eco-friendly sorbent for Congo Red (CR) and Methylene Blue (MB) removal from aqueous solutions. The biosorbent was characterized by Fourier transform infrared spectroscopy. Batch experiments were conducted to study the effect of pH, biosorbent dosage, initial concentration of adsorbates, contact time and temperature on the biosorption of the two dyes. The equilibrium adsorption data were analysed using Freundlich and Langmuir models. Both models fitted well the experimental data. The maximum biosorption capacity of the pretreated Streptomyces fradiae biomass was 46.64 mg g-1 for CR and 59.63 mg g-1 for MB, at a pH 6.0, with the contact time of 120 min, the biosorbent dosage of 2 g dm-3 and the temperature of 298 K. Lagergren and Ho kinetic models were used to analyse the kinetic data obtained from different batch experiments. The biosorption of both dyes followed better the pseudo-second order kinetic model. The calculated values for ?G, ?S, and ?H indicated that the biosorption of CR and MB onto the waste pretreated biomass was feasible, spontaneous, and exothermic in the selected temperature range and conditions.

scholarly journals Comparison of Adsorptive Removal of Total Nitrogen (T-N) and Total Phosphorous (T-P) in Aqueous Solution using Granular Activated Charcoal (GAC)

2013 ◽  
Vol 9 (1) ◽  
pp. 1822-1836
Author(s):  
Keon Sang Ryoo ◽  
Jong-Ha Choi ◽  
Yong Pyo Hong
Keyword(s):  
Aqueous Solution ◽  
Kinetic Model ◽  
Adsorption Capacity ◽  
Total Nitrogen ◽  
Activated Charcoal ◽  
Adsorption Equilibrium ◽  
Order Kinetic ◽  
Total Phosphorous ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The present study is to explore the possibility of utilizing granular activated charcoal (GAC) for the removal of total phosphorous (T-P) and total nitrogen (T-N) in aqueous solution. Batch adsorption studies were carried out to determine the influences of various factors like initial concentration, contact time and temperature. The adsorption data showed that GAC has a similar adsorption capacity for both T-N and T-P. The adsorption degree of T-N and T-P on GAC was highly concentration dependent. It was found that the adsorption capacity of GAC is quite favorable at a low concentration. At concentrations of 1.0 mg L-1 of T-P and 2.0 mg L-1 of T-N, approximately 97 % of adsorption was achieved by GAC. The equilibrium data were fitted well to the Langmuir isotherm model. The pseudo-second-order kinetic model appeared to be the better-fitting model because it has higher R2 compared with the pseudo-first-order and intra-particle kinetic model. The theoretical adsorption equilibrium qe,cal from pseudo-second-order kinetic model were relatively similar to the experimental adsorption equilibrium qe,exp. To evaluate the effect of thermodynamic parameters at different temperatures, the change in free energy ΔG, the enthalpy ΔH and the entropy ΔS were estimated. Except for adsorption of T-P at 278 K, the ΔG values obtained were all negative at the investigated temperatures. It indicates that the present adsorption system occurs spontaneously. The adsorption process of T-N by GAC was exothermic in nature, whereas T-P showed endothermic behavior. In addition, the positive values of ΔS imply that there was the increase in the randomness of adsorption of T-N and T-P at GAC-solution interface.  

Use of Natural Kaolinite Clay as an Adsorbent to Remove PB(II), CD(II), and CU(II) from Aqueous Solution

2014 ◽  
Vol 805 ◽  
pp. 581-584 ◽  
Author(s):  
Débora Martins Aragão ◽  
Maria de Lara P.M. Arguelho ◽  
Carolina Mangieri Oliveira Prado ◽  
José do Patrocinio Hora Alves
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Adsorption Process ◽  
Adsorption Equilibrium ◽  
Northeast Brazil ◽  
Order Kinetic ◽  
Kaolinite Clay ◽  
Adsorption Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Natural kaolinite clay collected in the State of Sergipe (northeast Brazil) was used as an adsorbent for the ions Pb2+, Cd2+, and Cu2+present in aqueous solution. Adsorption equilibrium was reached rapidly, enabling use of a contact time of 30 minutes, and maximum adsorption was achieved at pH 7.0. For all three metal ions, the adsorption data could be fitted using the Langmuir isotherm and the adsorption process obeyed a pseudo-second order kinetic model.

scholarly journals Synthesis of Large Pore LTL and MOR Zeolites and Use as Adsorbent for The Removal of Heavy Metal and Radioactive Metal Ions in Aqueous Solution

2021 ◽  
Author(s):  
Duy Hoai-Phuong Nguyen ◽  
Quang Thanh Le ◽  
Tung Cao Thanh Pham ◽  
Thanh Tu Le
Keyword(s):  
Aqueous Solution ◽  
Heavy Metal ◽  
Metal Ions ◽  
Adsorption Capacity ◽  
Order Kinetic ◽  
Experiment Data ◽  
Large Pore ◽  
Order Kinetic Model ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order

Abstract Heavy metal and radioactive ions can cause serious environmental problems if they are not completely removed from wastewater as well as in groundwater. In this study, large pore LTL and MOR zeolites were successfully synthesized and used as adsorbent to remove Pb2+, Cu2+, Zn2+, Cd2+, Cs+ and Sr2+ ions in aqueous solution. At low initial concentration (10 ppm), LTL and MOR zeolites effectively removed above metal ions with removal efficiency in the range of 95–99%. Both zeolites showed high affinity to Cs+ and Pb2+ ions with the adsorption capacity of LTL zeolite to Cs+ and Pb2+ were 278.8 mg/g and 141.4 mg/g, and that of MOR zeolite were 238.8 mg/g and 178.9 mg/g, respectively. The EDS results showed that Pb2+ ions from the aqueous solution were exchanged with exchangeable Na+ ions in MOR zeolite and K+ ions in LTL zeolite. The pseudo-second-order kinetic model and Langmuir isotherm model fitted better to experiment data on the adsorption of metal ions on both LTL and MOR zeolite. This result revealed that the adsorption of these metal ions on LTL and MOR zeolite was monolayer chemisorption. The equilibrium adsorption results showed that the microstructure of zeolite significantly affected the adsorption capacity of LTL and MOR zeolite on removal of tested metal ions.

scholarly journals Adsorption of Methylene Blue from Aqueous Solution by Pumpkin-Seed Residue

2020 ◽  
Vol 42 (1) ◽  
pp. 10-18
Author(s):  
Tae Hyun Gil ◽  
Wang Heon Lee ◽  
Johng-Hwa Ahn
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Adsorption Capacity ◽  
Contact Time ◽  
Sorption Process ◽  
Second Order ◽  
High Concentration ◽  
Pumpkin Seed ◽  
Freundlich Adsorption Isotherm ◽  
Pseudo Second Order

Objective : Present research discussed the utilization of pumpkin-seed residue (PSR) after oil extraction with methanol as an adsorbent for methylene blue (MB) removal from aqueous solution.Method : The experiment was carried out to evaluate the influence of PSR adsorbent dose (7.5-25 g/L), initial MB concentration (25-200 mg/L), contact time (30-120 min), pH (3-11), and temperature (293-333 K). Adsorption isotherms were modeled with the Langmuir, Freundlich, and Temkin isotherms. The kinetic data were analyzed using pseudo-first-order and pseudo-second-order models.Results and Discussion : A pseudo-equilibrium state was reached within 30 min of contact time at low initial MB concentration (25-50 mg/L) and 90 min at high concentration (100-200 mg/L). Increasing pH and temperature caused an increase in adsorption capacity. Thermodynamic studies demonstrated that the adsorption process was spontaneous with Gibb’s free-energy values ranging between -15.78 to -13.87 kJ/mol and endothermic with an enthalpy value of 0.011 kJ/mol. The adsorption equilibrium data fitted well with the Freundlich adsorption isotherm. The maximum monolayer adsorption capacity was 20.33 mg/g. Tempkin isotherm model clarified that the heat of sorption process was 6.28 J/mol. The adsorption kinetics was found to follow the pseudo-second order kinetics model and its rate constant was 0.002-0.278 g/mg･min.Conclusions : Findings of the present study indicated that the PSR can be successfully used for removal of MB from aqueous solution. Therefore, the PSR was shown to have good potential as a biosorbent for MB removal.

scholarly journals Modelling and Optimizing the Removal of Methylene Blue by a Mixture of Titaniferous Sand and Attapulgite Using Complete Factorial Design

2021 ◽  
Vol 17 (40) ◽  
pp. 88
Author(s):  
Kalidou Ba ◽  
Alpha Ousmane Toure ◽  
El Hadji Moussa Diop ◽  
Falilou Mbacke Sambe ◽  
Codou Guéye Mar Diop
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Desirability Function ◽  
Second Order ◽  
Order Kinetic ◽  
Methylene Blue Adsorption ◽  
Charge Potential ◽  
Adsorbate Concentration ◽  
Order Kinetic Model ◽  
Pseudo Second Order

This paper focuses on the removal of methylene blue by adsorption using a mixture of titaniferous sand and attapulgite. The different adsorbents were characterized by X-ray fluorescence spectroscopy and their different parameters such as pH, zero charge potential, and specific surface area were determined. The experiments performed were optimized and modeled by a full 2-level and 4-factor design. The four factors are the ratio of titaniferous sand and attapulgite, the concentration of methylene blue, pH, and time. These vary from 4 to 19, 20 to 100 mg/L, 2 to 9, and 30 to 150 min respectively. The study of the effects of the different factors showed that the effect of methylene blue concentration and pH significantly influence the adsorption capacity and removal efficiency of the dye. The optimum parameters (adsorbent ratio, adsorbate concentration, pH and time) obtained for the adsorption capacity through the desirability function are: 19, 100mg/L, 9 and 150min. Those obtained for the yield are: 4, 100mg/L, 9, 150min. The pseudo second order adsorption kinetics gave an equilibrium adsorption capacity qe (calculated) = 7.6863 mg/g which is almost equal to that obtained experimentally qe (exp) = 7.3562 mg/g. This shows that the pseudo second order kinetic model is the adequate mathematical model to describe the methylene blue adsorption phenomenon on the mixture of titaniferous sand and attapulgite. The thermodynamic study showed that the methylene blue adsorption reaction is exothermic, non-spontaneous, and the degree of disorder of the particles at the adsorbing surface decreases.

scholarly journals Determination of the Optimal Condition of Direct Blue Dye. Removal from Aqueous Solution Using Eggshell

2019 ◽  
Vol 70 (4) ◽  
pp. 1108-1113 ◽  
Author(s):  
Rana Abdullah Abbas ◽  
Ahlam Abdul-Rheem Farhan ◽  
Hussam Nadum Abdalraheem Al Ani ◽  
Aurelia Cristina Nechifor
Keyword(s):  
Aqueous Solution ◽  
Dye Removal ◽  
Polynomial Equation ◽  
Second Order ◽  
Blue Dye ◽  
Order Kinetic ◽  
Direct Blue ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Eggshells was used as a natural adsorbent to remove direct blue(DB) dye from aqueous solution and investigating the four factors that affect the adsorption of DB dye ; amount of eggshell rang (0.1 - 1g), initial concentration (10 - 60 mg/L ), time ( 5 - 45 min.) and pH (3 - 11). Central Composition Design with four variables and five levels coupled with response surface method was adopted to get a second order polynomial equation for dye removal percentage as the response, and to obtain the optimum conditions for maximum dye removal percentage ; which reach 84% with optimum point , eggshell (0.835 g) ,time (24min.) , initial dye concentration ( 10 mg/L) , pH (4.2). The most effecting factors on dye removal are pH and initial dye concentration. Langmuir, Freundich model gives good fitting with (R2 ]0.98). The process of adsorption of DB dye on eggshell fitted a pseudo-second order kinetic model.

scholarly journals Novel Ag/Kaolin Nanocomposite as Adsorbent for Removal of Acid Cyanine 5R from Aqueous Solution

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Saeedeh Hashemian ◽  
Mohammad Reza Shahedi
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Adsorption Process ◽  
Alkaline Condition ◽  
Order Kinetic ◽  
Nano Composite ◽  
Order Kinetic Model ◽  
Endothermic Process ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order

Ag/kaolin nanocomposite was prepared by reduction of Ag+ion with ethanol at alkaline condition on kaolin surface. Nanocomposite was characterized by FTIR, XRD, TEM, and BET methods. Results showed the Ag/kaolin composite has particle size 50 nm. The surface area was increased from kaolin to Ag/kaolin from 1.0215 to 7.409 m2 g−1, respectively. Ag/kaolin nanocomposite was used for adsorption of acid cyanine 5R (AC5R) from aqueous solution. The effect of parameters such as contact time, pH, and mass of nano composite has been investigated. The maximum percentage of adsorption of AC5R was found at pH 3 and contact time of 60 min. The higher percentage removal of AC5R by Ag/kaolin than kaolin can be attributed to catalytic activity of Ag on the surface of kaolin. The experimental data was fitted by pseudo-second-order kinetic model. The adsorption isotherm data could be well interpreted by Langmuir isotherm model. From the results of thermodynamic study, the adsorption process of AC5R onto Ag/kaolin nanocomposite was spontaneous and endothermic process. The process is clean and safe for purifying of water pollution.

Preparation and Methylene Blue Adsorption Characteristics of Highly Mesoporous Rice Husk Active Carbon Prepared by an Alkali-Saving and Equipment-Friendly Method

2013 ◽  
Vol 448-453 ◽  
pp. 182-187 ◽  
Author(s):  
Da Wei Li ◽  
Xi Feng Zhu
Keyword(s):  
Methylene Blue ◽  
Removal Efficiency ◽  
Rice Husk ◽  
Active Carbon ◽  
Dye Removal ◽  
Order Kinetic ◽  
Mesopore Volume ◽  
Order Kinetic Model ◽  
Naoh Solution ◽  
Pseudo Second Order

Highly mesoporous active carbon for removing methylene blue (MB) from aqueous solution was prepared from pyrolyzed rice husk by combination of CO2activation and NaOH-solution boiling. The preparation method was found to be alkali-saving and equipment-friendly. The prepared active carbon exhibited high mesoporosity (79.1%), with mesopore volume and specific surface area up to 0.619 mL/g and 899 m2/g, respectively. At initial MB concentrations of 240-380 mg/L, the MB removal efficiency of the prepared active carbon ranged from 92% to more than 99%, fairly comparable to that of the highly mesoporous commercial active carbon used for reference. The adsorption of MB onto the prepared active carbon well followed the pseudo second-order kinetic model and Langmuir isotherm. This study indicated that highly mesoporous active carbon with large dye removal efficiency could be prepared from rice husk by an alkali-saving and equipment-friendly process.

Sign in / Sign up

Export Citation Format

Share Document