Banana Fibers as Sorbent for Removal of Acid Green Dye from Water

In this study, banana fibers extracted from banana leaves, stem, and stalk were used to remove acid green dye from aqueous solution. Three initial concentrations (750, 1000, and 1500 ppm) were chosen to determine the kinetic characteristics of the banana fiber sorbents at 25°C, agitation speed of 200 rpm, and total contact time of 3 hours. The pseudo-first-order, pseudo-second-order, and Dunwald-Wagner kinetic models were applied to the experimental kinetic data. For isotherm study, the batch experiments were performed at 25°C, initial pH 2, agitation speed of 200 rpm, and initial concentrations between 100 and 2000 ppm. The experimental data was fitted to the Langmuir, Freundlich, Dubinin-Radushkevich, and Temkin isotherms. The equilibrium was achieved in less than 90 minutes. The removal of the acid green dye was found to be following closely the pseudo-second-order kinetic model. For equilibrium study, the Freundlich isotherm was found to fit well with adsorption of acid green dye on the banana leaves, stem, and stalk sorbents. The calculated mean free energy of 4–11 J/mol indicated that the sorption process was mostly physical in nature. Experimental results also showed the adsorption performance is greatly affected by the initial solution pH.

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Mathematical Modelling for Copper and Lead Adsorption on Coffee Grounds

Proccedings of 10th International Conference "Environmental Engineering" ◽

10.3846/enviro.2017.007 ◽

2017 ◽

Author(s):

Jurgita Seniūnaitė ◽

Rasa Vaiškūnaitė ◽

Kristina Bazienė

Keyword(s):

Heavy Metals ◽

Mathematical Modelling ◽

Adsorption Kinetics ◽

Adsorption Process ◽

Freundlich Isotherm ◽

Sorption Process ◽

Second Order ◽

Order Kinetic ◽

Coffee Grounds ◽

Pseudo Second Order

Research studies on the adsorption kinetics are conducted in order to determine the absorption time of heavy metals on coffee grounds from liquid. The models of adsorption kinetics and adsorption diffusion are based on mathe-matical models (Cho et al. 2005). The adsorption kinetics can provide information on the mechanisms occurring be-tween adsorbates and adsorbents and give an understanding of the adsorption process. In the mathematical modelling of processes, Lagergren’s pseudo-first- and pseudo-second-order kinetics and the intra-particle diffusion models are usually applied. The mathematical modelling has shown that the kinetics of the adsorption process of heavy metals (copper (Cu) and lead (Pb)) is more appropriately described by the Lagergren’s pseudo-second-order kinetic model. The kinetic constants (k2Cu = 0.117; k2Pb = 0,037 min−1) and the sorption process speed (k2qeCu = 0.0058–0.4975; k2qePb = 0.021–0.1661 mg/g per min) were calculated. After completing the mathematical modelling it was calculated that the Langmuir isotherm better reflects the sorption processes of copper (Cu) (R2 = 0.950), whilst the Freundlich isotherm – the sorption processes of lead (Pb) (R2 = 0.925). The difference between the mathematically modelled and experimen-tally obtained sorption capacities for removal of heavy metals on coffee grounds from aqueous solutions is 0.059–0.164 mg/l for copper and 0.004–0.285 mg/l for lead. Residual concentrations of metals in a solution showed difference of 1.01 and 0.96 mg/l, respectively.

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Itaconic acid-modified layered double hydroxide as a ‎novel adsorbent for effective removal of Congo red from aqueous solutions

10.21203/rs.3.rs-345643/v1 ◽

2021 ◽

Author(s):

Mohammad Dinari ◽

Shirin Shabani

Keyword(s):

Layered Double Hydroxide ◽

Itaconic Acid ◽

Congo Red ◽

Aqueous Media ◽

Freundlich Isotherm ◽

Second Order ◽

Order Kinetic ◽

Solution Ph ◽

Pseudo Second Order ◽

Double Hydroxide

Abstract Herein, we report the synthesis of Cu-Ca-Al/NO3-based layered double hydroxide through co-precipitation methodology. The prepared layered double hydroxide was then modified with itaconic acid. The physicochemical properties of the prepared materials were studied using Fourier transform-infrared spectroscopy, scanning electron microscopy, X-ray diffraction analysis, thermogravimetric analysis, and nitrogen adsorption/desorption technique. The prepared materials were then applied as novel adsorbents for the removal of Congo red as a model of an anionic dye from aqueous media. To reach maximum adsorption, the effect of parameters including sample solution pH, adsorbent amount, contact time, and initial concentration of Congo red on the adsorption process was investigated. Kinetic studies were also conducted to study the mechanism of adsorption. In this regard, the kinetic models of pseudo-first-order, pseudo-second-order, Elovich, and intra-particle diffusion were studied. The results showed that the adsorption of Congo red onto Cu-Ca-Al-LDH and LDH-ITA adsorbents followed the pseudo-second-order kinetic model. To evaluate the equilibrium adsorption data, different isotherms including Langmuir, Freundlich, and Dubinin-Radushkevich were also applied. The data revealed that the Freundlich isotherm provided the best fit with the equilibrium data of both adsorbents. Maximum adsorption capacities of 81 and 84 mg g− 1 were obtained using Cu-Ca-Al-LDH and LDH-ITA adsorbents, respectively.

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Mass-transfer processes in the adsorption of crystal violet by activated carbon derived from pomegranate peels: Kinetics and thermodynamic studies

Journal of Engineered Fibers and Fabrics ◽

10.1177/1558925020919847 ◽

2020 ◽

Vol 15 ◽

pp. 155892502091984

Author(s):

Moussa Abbas ◽

Zahia Harrache ◽

Mohamed Trari

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Crystal Violet ◽

Agitation Speed ◽

Second Order ◽

Point Of Zero Charge ◽

Order Kinetic ◽

Solution Ph ◽

Pseudo Second Order ◽

Adsorbent Dose

This study investigates the potential use of activated carbon, prepared from pomegranate peels, as an adsorbent activated using H3PO4 and its ability to remove crystal violet from an aqueous solution. The adsorbent was characterized by the Brunauer–Emmett–Teller method (specific surface area: 51.0674 m2 g−1) and point of zero charge (pHPZC = 5.2). However, some examined factors were found to have significant impacts on the adsorption capacity of activated carbon derived from pomegranate peels such as the initial dye concentration (5–15 mg L−1), solution pH (2–14), adsorbent dose (1–8 g L−1), agitation speed (100–700 r/min), and temperature (298–338 K). The best adsorption capacity was found at pH 11 with an adsorbent dose of 1 g L−1, an agitation speed at 400 r/min, and a contact time of 45 min. The adsorption mechanism of crystal violet onto activated carbon derived from pomegranate peels was studied using the pseudo-first-order, pseudo-second-order, Elovich, and Webber–Morris diffusion models. The adsorption kinetics were found to rather follow a pseudo-second order kinetic model with a determination coefficient ( R2) of 0.999. The equilibrium adsorption data for crystal violet adsorbed onto activated carbon derived from pomegranate peels were analyzed by the Langmuir, Freundlich, Elovich, and Temkin models. The results indicate that the Langmuir model provides the best correlation with qmax capacities of 23.26 and 76.92 mg g−1 at 27°C and 32°C, respectively. The adsorption isotherms at different temperatures have been used for the determination of thermodynamic parameters like the free energy, enthalpy, and entropy to predict the nature of adsorption process. The negative values Δ G0 (−5.221 to −1.571 kJ mol−1) and Δ H0 (−86.141 kJ mol−1) indicate that the overall adsorption is spontaneous and exothermic with a physisorption process. The adsorbent derived from pomegranate peels was found to be very effective and suitable for the removal of reactive dyes from aqueous solutions, due to its availability, low-cost preparation, and good adsorption capacity.

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Phragmites karkaas a Biosorbent for the Removal of Mercury Metal Ions from Aqueous Solution: Effect of Modification

Journal of Chemistry ◽

10.1155/2015/293054 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 16

Author(s):

Muhammad Hamid Raza ◽

Aqsa Sadiq ◽

Umar Farooq ◽

Makshoof Athar ◽

Tajamal Hussain ◽

...

Keyword(s):

Aqueous Solution ◽

Metal Ion ◽

Freundlich Isotherm ◽

Agitation Speed ◽

Second Order ◽

Ion Concentration ◽

Order Kinetic ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Phragmites Karka

Batch scale studies for the adsorption potential of novel biosorbentPhragmites karka(Trin), in its natural and treated forms, were performed for removal of mercury ions from aqueous solution. The study was carried out at different parameters to obtain optimum conditions of pH, biosorbent dose, agitation speed, time of contact, temperature, and initial metal ion concentration. To analyze the suitability of the process and maximum amount of metal uptake, Dubinin-Radushkevich (D-R) model, Freundlich isotherm, and Langmuir isotherm were applied. The values ofqmaxfor natural and treated biosorbents were found at 1.79 and 2.27 mg/g, respectively. The optimum values of contact time and agitation speed were found at 50 min and 150 rpm for natural biosorbent whereas 40 min and 100 rpm for treated biosorbent, respectively. The optimum biosorption capacities were observed at pH 4 and temperature 313 K for both naturalP. karkaand treatedP. karka.RLvalues indicate that comparatively treatedP. karkawas more feasible for mercury adsorption compared to naturalP. karka. Both pseudo-first-order and pseudo-second-order kinetic models were applied and it was found that data fit best to the pseudo-second-order kinetic model. Thermodynamic studies indicate that adsorption process was spontaneous, feasible, and endothermic.

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Study of the kinetics and the adsorption isotherm of cadmium(II) from aqueous solution using green algae (Ulva lactuca) biomass

Water Science & Technology ◽

10.2166/wst.2015.359 ◽

2015 ◽

Vol 72 (9) ◽

pp. 1505-1515 ◽

Cited By ~ 9

Author(s):

H. Asnaoui ◽

A. Laaziri ◽

M. Khalis

Keyword(s):

Aqueous Solution ◽

Metal Ions ◽

Low Cost ◽

Freundlich Isotherm ◽

Second Order ◽

Ulva Lactuca ◽

Order Kinetic ◽

Solution Ph ◽

Algae Biomass ◽

Pseudo Second Order

Batch experiments were conducted to study the adsorption of hazardous cadmium onto low-cost algae biomass in aqueous solution with respect to concentration of adsorbate, adsorbent dosage, contact time, solution pH and temperature. Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms and the isotherm constants were determined. The activation energy of adsorption was also evaluated for the adsorption of cadmium onto Ulva lactuca biomass. Experimental data were tested in terms of biosorption kinetics using pseudo-first-order and pseudo-second-order kinetic models. The results showed that the biosorption processes of Cd(II) followed well pseudo-second-order kinetics. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the metal ions by Ulva lactuca biomass. Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The biosorption capacity of Ulva lactuca biomass for cadmium was found to be 3.02 mg/g at pH 5.60 min equilibrium time and 20 °C. The mean free energy which was calculated was 6.24 kJ/mol for Cd(II) biosorption, which shows that the adsorption is physical. The calculated thermodynamic parameters (ΔG0, ΔH0 and ΔS0) showed that the biosorption of Cd(II) onto Ulva lactuca biomass was feasible, spontaneous and exothermic under examined conditions. The results indicate that algae Ulva lactuca could be employed as a low-cost material for the removal of metal ions from aqueous solution.

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Treatment of textile effluents by chloride-intercalated Zn-, Mg- and Ni-Al layered double hydroxides

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2016.041 ◽

2016 ◽

Vol 7 (3) ◽

pp. 307-318 ◽

Cited By ~ 7

Author(s):

F. Z. Mahjoubi ◽

A. Khalidi ◽

O. Cherkaoui ◽

R. Elmoubarki ◽

M. Abdennouri ◽

...

Keyword(s):

Oxygen Demand ◽

Freundlich Isotherm ◽

Chloride Ions ◽

Second Order ◽

Cod Removal ◽

Precipitation Method ◽

Isotherm Models ◽

Order Kinetic ◽

Solution Ph ◽

Pseudo Second Order

This work involved the preparation, characterization and dyes removal ability of Zn-Al, Mg-Al and Ni-Al layered double hydroxide (LDH) minerals intercalated by chloride ions. The materials were synthetized by the co-precipitation method. X-ray diffraction, Fourier transform infrared, thermogravimetric-differential thermal analysis and transmission electron microscopy characterization exhibited a typical hydrotalcite structure for all the samples. Adsorption experiments for methyl orange were performed in terms of solution pH, contact time and initial dye concentration. Experimental results indicate that the capacity of dye uptake augmented rapidly within the first 60 min and then stayed practically the same regardless of the concentration. Maximum adsorption occurred with acidic pH medium. Kinetic data were studied using pseudo-first-order and pseudo-second-order kinetic models. Suitable correlation was acquired with the pseudo-second-order kinetic model. Equilibrium data were fitted to Langmuir and Freundlich isotherm models. The maximum Langmuir monolayer adsorption capacities were 2,758, 1,622 and 800 mg/g, respectively, for Zn-Al-Cl, Mg-Al-Cl and Ni-Al-Cl. The materials were later examined for the elimination of color and chemical oxygen demand (COD) from a real textile effluent wastewater. The results indicated that the suitable conditions for color and COD removal were acquired at pH of 5. The maximum COD removal efficiency from the effluent was noted as 92.84% for Zn-Al-Cl LDH.

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Adsorptive removal of direct red 80 and methylene blue from aqueous solution by potato peels: a comparison of anionic and cationic dyes

Water Science & Technology ◽

10.2166/wst.2021.075 ◽

2021 ◽

Author(s):

Khawla Ben Jeddou ◽

Fatma Bouaziz ◽

Fadia Ben Taheur ◽

Oumèma Nouri-Ellouz ◽

Raoudha Ellouz-Ghorbel ◽

...

Keyword(s):

Methylene Blue ◽

Adsorption Process ◽

Fourier Transforms ◽

Freundlich Isotherm ◽

Second Order ◽

Order Kinetic ◽

Solution Ph ◽

Model Calculations ◽

Pseudo Second Order ◽

Potato Peels

Abstract Adsorption of direct red 80 (DR 80) and methylene blue (MB) from aqueous solutions on potato peels (PP) has been compared. The use of peels in decontamination technology is very promising given the near zero-cost for the synthesis of those adsorbents. The selected potato peels were first analyzed by scanning using electron microscopy (SEM) and Fourier transforms infra red spectroscopy (FTIR). Then the adsorption behavior was studied in a batch system. The adsorption process is affected by various parameters such as the solution pH (2–11), the initial concentration of the dye (20, 50, 100, 150 and 200 mg L−1), the adsorbent dose (0.1%–3%), the temperature (303.16 K, 313.16 K, and 323.16 K), agitation (up to 250 rpm), as well as the contact time. Adsorption isotherms of the studied dye on the adsorbent were determined and compared with the Langmiur, Freundlich and Temkin adsorption models. The results show that the data was most similar to the Freundlich isotherm (R2 = 0.99). The maximum adsorption capacities (Qmax) of MB and DR 80 by the PP at temperatures 303.16 K, 313.16 K and 323.16 K were found to be approximately 97.08 mg g−1; 45.87 mg g−1; 61.35 mg g−1 and 27.778 mg g−1; 45.45 mg g−1; and 32.258 mg g−1. The kinetic data was compared to the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. This revealed that adsorption of methylene blue onto PP abided mostly to the pseudo-second-order kinetic model. Calculations of various thermodynamic parameters such as enthalpy change (ΔH), entropy change (ΔS), and free energy change (ΔG) display the endothermic and spontaneous nature of the adsorption process.

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Adsorption of Chromium Ions on Activated Carbon Produced from Cow Bones

Iraqi Journal of Chemical and Petroleum Engineering ◽

10.31699/ijcpe.2019.2.4 ◽

2019 ◽

Vol 20 (2) ◽

pp. 23-32

Author(s):

Marah Waleed Khalid ◽

Sami D. Salman

Keyword(s):

Surface Area ◽

Kinetic Equations ◽

Freundlich Isotherm ◽

Second Order ◽

Raw Material ◽

Isotherm Models ◽

Order Kinetic ◽

Solution Ph ◽

Chromium Ions ◽

Pseudo Second Order

Due to the broad range uses of chromium for industrial purposes, besides its carcinogenic effect, an efficient, cost effective removal method should be obtained. In this study, cow bones as a cheap raw material were utilized to produce active carbon (CBAC) by physiochemical activation, which was characterized using: SEM to investigate surface morphology and BET to estimate the specific surface area. The best surface area of CBAC was 595.9 m2/gm which was prepared at 600 ᵒC activation temperature and impregnation ratio of 1:1.5. CBAC was used in aqueous chromium ions adsorption. The investigated factors and their ranges are: initial concentration (10-50 mg/L), adsorption time (30-300 min), temperature (20-50 ᵒC) and solution pH (2-11). Isotherm of adsorption and its kinetics were studied. The adsorption process was modeled statistically and was represented by an empirical model. Equilibrium data were fitted to the Langmuir and Freundlich isotherm models and the data best represented by Freundlich isotherm. Pseudo- first order and pseudo- second order kinetic equations were utilized to study adsorption kinetics, where chromium adsorption on CBAC fitted pseudo- second order fitted the data more adequately. The best removal efficiency was found to be 94.32%.

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Bioremediation of Ni2+, Cd2+ and Pb2+ from aqueous solution using chemically modified Newbouldia Leavis seed pod. Kinetics and Intraparticle Diffusivities.

Journal of Chemical Society of Nigeria ◽

10.46602/jcsn.v46i2.595 ◽

2021 ◽

Vol 46 (2) ◽

Author(s):

O.K. Amadi ◽

F.K. Ekuma ◽

B. N. Uche

Keyword(s):

Aqueous Solution ◽

Sorption Process ◽

Second Order ◽

Order Kinetic ◽

Solution Ph ◽

First Order ◽

Biosorption Process ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Kinetic Plots

This study investigates the biosorption of Ni2+, Cd2+ and Pb2+ from aqueous solution by modified Newbouldia Leavis seed pod. The modification was done by acid treating air-dried activated Newbouldia Leavis seed pod by dissolving it in excess 1.0 M Mercapto acetic acid (HSCH2COOH) solution, stirred for 30 minutes and left to stand for 24 hours at 30 oC, filtered off using WhatmanNo. 41 filter paper and were air dried. The effects of solution pH and contact time were evaluated. The results showed that maximum Cd2+ and Ni2+ adsorption of 7.9872 mg/g and 7.9809 mg/g respectively occurred at pH of 6.0 while that of Pb2+ was 8.0000 mg/g, at a pH of 4.0. The optimum time for maximum adsorption of the three heavy metal ions were 110 min. The kinetic data revealed that the sorption process could best be described by the pseudo – second order kinetic model. The R2 values for the pseudo – second order kinetic plots were unity and were higher than first order reversible model and pseudo – first order plots. Moreover, the values of qcal and qexp obtained for pseudo – second order plots were very close indicating that the biosorption process followed the pseudo-second order kinetics. However, the transport mechanism for the process involved both intra-particle and liquid film diffusion.

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Isothermal, Kinetic, and Thermodynamic Studies of Graphene Oxide Adsorption on Silk

AATCC Journal of Research ◽

10.14504/ajr.8.5.3 ◽

2021 ◽

Vol 8 (5) ◽

pp. 18-29

Author(s):

Arobindo Chatterjee ◽

Vinit Kumar Jain

Keyword(s):

Graphene Oxide ◽

Freundlich Isotherm ◽

Sorption Process ◽

Order Kinetic ◽

Solution Ph ◽

Thermodynamic Studies ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Isothermal Kinetic ◽

Kinetics Of

The properties of graphene enriched silk depend on the amount of graphene oxide (GO) adsorption on silk. GO dipping parameters include the GO solution pH, initial GO concentration, dipping time and temperature, and the type of substrate. The effects of GO dipping parameters on the sorption process are studied to achieve the maximum GO adsorption on the silk surface for the preparation of an economical graphene/silk-based textile product. In addition, equilibrium isotherms, kinetics, and thermodynamics of GO adsorption on the silk surface in a batch sorption process are examined to understand the adsorption mechanism. The Freundlich isotherm best describes the adsorption of GO onto the silk. A pseudo-second order kinetic model best describes the kinetics of GO adsorption. Thermodynamic studies reveal that GO adsorption is spontaneous and exothermic.

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