The adsorption of lemon yellow dye using cationic cellulose fibers from rice straw as a sustainable biosorbent in aqueous media

A biosorbent was prepared from the cellulose fibers found in rice straw through cationic modification. The effects of the dosage, pH, contact time, and initial concentration of lemon yellow dye were explored. The static adsorption results showed that cationic modification drastically improved the adsorption capacity of straw cellulose fiber. The maximum equilibrium adsorption capacity value was 137.6 mg/g and the highest removal reached 99%. The pseudo-second-order kinetic model was a good fit for the adsorption process, together with the Langmuir isotherm model. The adsorption reaction was spontaneous, and the adsorption process was an exothermic reaction, which was shown by the thermodynamic model. As the adsorption time became longer, the effluent concentration became larger until reaching equilibrium. The time was 420 min. After desorption using a dilute NaOH solution, the maximum adsorption capacity was still 36.1 mg/g and the maximum removal still reached 36.2%. The parameters calculated from the Yoon-Nelson model have a good fit with the experimental data. In short, cationic straw cellulose fiber is an effective and easy to prepare biosorbent. This work offers a new method for dye wastewater purification and solves the effective utilization of rice straw resources.

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Efficient and Selective Adsorption of Gold Ions from Wastewater with Polyaniline Modified by Trimethyl Phosphate: Adsorption Mechanism and Application

Polymers ◽

10.3390/polym11040652 ◽

2019 ◽

Vol 11 (4) ◽

pp. 652 ◽

Cited By ~ 5

Author(s):

Wang ◽

Zhao ◽

Wang ◽

Zhang ◽

Zhang

Keyword(s):

Adsorption Capacity ◽

Adsorption Process ◽

Selective Adsorption ◽

Interaction Mechanism ◽

Single Layer ◽

Phosphate Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Trimethyl Phosphate ◽

Selective Recovery

The selective recovery of gold from wastewater is necessary because it is widely used in various fields. In this study, a new polymeric adsorbent (TP-AFC) was prepared by modifying polyaniline with trimethyl phosphate for the selective recovery of gold from wastewater. Bath experiments were carried out to explore the adsorption capacity and mechanism. The optimum pH of adsorption is 4. The adsorption equilibrium is reached at 840 min. The maximum adsorption capacity is 881 mg/g and the adsorption was a spontaneous endothermic process. The adsorption process fitted well with pseudo second-order kinetic and the Langmuir-models. The single-layer chemisorption governed the adsorption process. In addition, the application in wastewater indicated that the interfering ions had no effect on the adsorption of gold ions. TP-AFC has good selectivity. The interaction mechanism was mainly ion exchange and complexation. In general, TP-AFC was successfully prepared and has an excellent future in practical application.

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Adsorption of Basic and Acidic Dyes onto Agricultural Wastes

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.70.12 ◽

2016 ◽

Vol 70 ◽

pp. 12-26 ◽

Cited By ~ 1

Author(s):

Nnaemeka John Okorocha ◽

J. Josphine Okoji ◽

Charles Osuji

Keyword(s):

Adsorption Capacity ◽

Contact Time ◽

Adsorption Process ◽

Aqueous Media ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Thermodynamic Quantities ◽

Order Kinetic ◽

Dyes Adsorption ◽

Adsorbent Dose

The potential of almond leaves powder, (ALP) for the removal of Crystal violet (CV) and Congo red (CR) dyes from aqueous solution was investigated. The adsorbent (ALP) was characterized by FTIR and SEM analysis. Batch adsorption studies were conducted and various parameters such as contact time, adsorbent dosage, initial dye concentration, pH and temperature were studied to observe their effects in the dyes adsorption process. The optimum conditions for the adsorption of CV and CR dyes onto the adsorbent (ALP) was found to be: contact time (100mins), pH (10.0), temperature (343K) for an initial CV dye concentration of 50mg/L using adsorbent dose of 1.0g and contact time (100mins), pH (2.0), temperature (333K) for an initial CR dye concentration of 50mg/L using adsorbent dose 1.0g respectively. The experimental equilibrium adsorption data fitted best and well to the Freundlich isotherm model for both CV and CR dyes adsorption. The maximum adsorption capacity of ALP was found to be 22.96mg/g and 7.77mg/g for the adsorption of CV and CR dyes respectively. The kinetic data conformed to the pseudo-second-order kinetic model. Thermodynamic quantities such as Gibbs free energy (ΔG0), enthalpy (ΔH0) and entropy (ΔS0) were evaluated and the negative values of ΔG0obtained for both dyes indicate the spontaneous nature of the adsorption process while the positive values of ΔH0and ΔS0obtained indicated the endothermic nature and increased randomness during the adsorption process respectively for the adsorption of CV and CR onto ALP. Based on the results obtained such as good adsorption capacity, rapid kinetics, and its low cost, ALP appears to be a promising adsorbent material for the removal of CV and CR dye stuff from aqueous media.

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Sheet-like Skeleton Carbon Derived from Shaddock Peels with Hierarchically Porous Structures for Ultra-Fast Removal of Methylene Blue

Water ◽

10.3390/w13182554 ◽

2021 ◽

Vol 13 (18) ◽

pp. 2554

Author(s):

Panlong Dong ◽

Hailin Liu ◽

Shengrui Xu ◽

Changpo Chen ◽

Suling Feng ◽

...

Keyword(s):

Methylene Blue ◽

Adsorption Capacity ◽

Surface Area ◽

Adsorption Process ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Initial Concentration ◽

Hierarchically Porous ◽

Column Adsorption

To remove the pollutant methylene blue (MB) from water, a sheet-like skeleton carbon derived from shaddock peels (SPACs) was prepared by NaOH activation followed by a calcination procedure under nitrogen protection in this study. Characterization results demonstrated that the as-prepared SPACs displayed a hierarchically porous structure assembled with a thin sheet-like carbon layer, and the surface area of SPAC-8 (activated by 8 g NaOH) was up to 782.2 m2/g. The as-prepared carbon material presented an ultra-fast and efficient adsorption capacity towards MB due to its macro-mesoporous structure, high surface area, and abundant functional groups. SPAC-8 showed ultrafast and efficient removal capacity for MB dye. Adsorption equilibrium was reached within 1 min with a removal efficiency of 99.6% at an initial concentration of 100 mg/g under batch adsorption model conditions. The maximum adsorption capacity for MB was up to 432.5 mg/g. A pseudo-second-order kinetic model and a Langmuir isotherm model described the adsorption process well, which suggested that adsorption rate depended on chemisorption and the adsorption process was controlled by a monolayer adsorption, respectively. Furthermore, column adsorption experiments showed that 96.58% of MB was removed after passing through a SPAC-8 packed column with a flow rate of 20 mL/min, initial concentration of 50 mg/L, and adsorbent dosage of 5 mg. The as-prepared adsorbent displays potential value in practical applications for dye removal due to its ultrafast and efficient adsorption capacity.

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Platinum (IV) Recovery from Waste Solutions by Adsorption onto Dibenzo-30-crown-10 Ether Immobilized on Amberlite XAD7 Resin–Factorial Design Analysis

Molecules ◽

10.3390/molecules25163692 ◽

2020 ◽

Vol 25 (16) ◽

pp. 3692

Author(s):

Oana Buriac ◽

Mihaela Ciopec ◽

Narcis Duţeanu ◽

Adina Negrea ◽

Petru Negrea ◽

...

Keyword(s):

Experimental Data ◽

Adsorption Capacity ◽

Thermodynamic Parameters ◽

Adsorption Isotherms ◽

Contact Time ◽

Adsorption Process ◽

Electrical Contacts ◽

Bet Surface Area ◽

Maximum Adsorption Capacity ◽

Order Kinetic

Platinum is a precious metal with many applications, such as: catalytic converters, laboratory equipment, electrical contacts and electrodes, digital thermometers, dentistry, and jewellery. Due to its broad usage, it is essential to recover it from waste solutions resulted out of different technological processes in which it is used. Over the years, several recovery techniques were developed, adsorption being one of the simplest, effective and economical method used for platinum recovery. In the present paper a new adsorbent material (XAD7-DB30C10) for Pt (IV) recovery was used. Produced adsorbent material was characterized by X-ray dispersion (EDX), scanning electron microscopy (SEM) analysis, Fourier Transform Infrared Spectroscopy and Brunauer-Emmett-Teller (BET) surface area analysis. Adsorption isotherms, kinetic models, thermodynamic parameters and adsorption mechanism are presented in this paper. Experimental data were fitted using three non-linear adsorption isotherms: Langmuir, Freundlich and Sips, being better fitted by Sips adsorption isotherm. Obtained kinetic data were correlated well with the pseudo-second-order kinetic model, indicating that the chemical sorption was the rate-limiting step. Thermodynamic parameters (ΔG°, ΔH°, ΔS°) showed that the adsorption process was endothermic and spontaneous. After adsorption, metallic platinum was recovered from the exhausted adsorbent material by thermal treatment. Adsorption process optimisation by design of experiments was also performed, using as input obtained experimental data, and taking into account that initial platinum concentration and contact time have a significant effect on the adsorption capacity. From the optimisation process, it has been found that the maximum adsorption capacity is obtained at the maximum variation domains of the factors. By optimizing the process, a maximum adsorption capacity of 15.03 mg g−1 was achieved at a contact time of 190 min, initial concentration of 141.06 mg L−1 and the temperature of 45 °C.

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A Study of the Adsorption and Removal of Sb(III) from Aqueous Solution by Fe(III) Modified Proteus cibarius with Mechanistic Insights Using Response Surface Methodology

Processes ◽

10.3390/pr9060933 ◽

2021 ◽

Vol 9 (6) ◽

pp. 933

Author(s):

Xiaojian Li ◽

Renjian Deng ◽

Zhie Tang ◽

Saijun Zhou ◽

Xing Zeng ◽

...

Keyword(s):

Response Surface Methodology ◽

Adsorption Capacity ◽

Response Surface ◽

Adsorption Process ◽

Isotherm Model ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Adsorption Time ◽

Initial Concentration ◽

Adsorbent Dose

Environmental pollution caused by excessive Sb(III) in the water environment is a global issue. We investigated the effect of processing parameters, their interaction and mechanistic details for the removal of Sb(III) using an iron salt-modified biosorbent (Fe(III)-modified Proteus cibarius (FMPAs)). Our study evaluated the optimisation of the adsorption time, adsorbent dose, pH, temperature and the initial concentration of Sb(III). We use response surface methodology to optimize this process, determining optimal processing conditions and the adsorption mechanism evaluated based on isotherm model and adsorption kinetics. The results showed that—(1) the optimal conditions for the adsorption of Sb(III) by FMPAs were an adsorption time of 2.2 h, adsorbent dose of 3430 mg/L, at pH 6.0 and temperature 44.0 °C. For the optimum initial concentration of Sb(III) 27.70 mg/L, the removal efficiency of Sb(III) reached 97.60%. (2) The adsorption process for Sb(III) removal by FMPAs conforms to the Langmuir adsorption isotherm model, and its maximum adsorption capacity (qmax) is as high as 30.612 mg/g. A pseudo-first-order kinetic model provided the best fit to the adsorption process, classified as single layer adsorption and chemisorption mechanism. (3) The adsorption of Sb(III) takes place via the hydroxyl group in Fe–O–OH and EPS–Polyose–O–Fe(OH)2, which forms a new complex Fe–O–Sb and X≡Fe–OH. The study showed that FMPAs have higher adsorption capacity for Sb(III) than other previously studied sorbents and with low environmental impact, it has a great potential as a green adsorbent for Sb(III) in water.

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Studies on the Removal of Cadmium Toxic Metal Ions by Natural Clays from Aqueous Solution by Adsorption Process

Journal of Chemistry ◽

10.1155/2021/7873488 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Rajaa Bassam ◽

Achraf El hallaoui ◽

Marouane El Alouani ◽

Maissara Jabrane ◽

El Hassan El Khattabi ◽

...

Keyword(s):

Adsorption Capacity ◽

Adsorption Process ◽

Metal Removal ◽

Heavy Metal Removal ◽

Toxic Metal ◽

Ion Concentration ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Solution Ph ◽

Natural Clays

The aim of this study is the valorization of the Moroccan clays (QC-MC and QC-MT) from the Middle Atlas region as adsorbents for the treatment of water contaminated by cadmium Cd (II) ions. The physicochemical properties of natural clays are characterized by ICP-MS, XRD, FTIR, and SEM techniques. The adsorption process is investigated as a function of adsorbent mass, solution pH, contact time, temperature, and initial Cd (II) ion concentration. The kinetic investigation shows that the adsorption equilibrium of Cd (II) ions by both natural clays is reached after 30 min for QC-MT and 45 min for QC-MC and fits well to a pseudo-second-order kinetic model. The isotherm study is best fitted by a Freundlich model, with the maximum adsorption capacity determined by the linear form of the Freundlich isotherm being 4.23 mg/g for QC-MC and 5.85 mg/g for QC-MT at 25°C. The cadmium adsorption process was thermodynamically spontaneous and exothermic. The regeneration process showed that these natural clays had excellent recycling capacity. Characterization of the Moroccan natural clays before and after the adsorption process through FTIR, SEM, XRD, and EDX techniques confirmed the Cd (II) ion adsorption on the surfaces of both natural clay adsorbents. Overall, the high adsorption capacity of both natural clays for Cd (II) ions removal compared to other adsorbents motioned in the literature indicated that these two natural adsorbents are excellent candidates for heavy metal removal from aqueous environments.

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Preparation of molecular imprinted polymer based on attapulgite and evaluation of its performance for adsorption of benzoic acid in water

Water Science & Technology ◽

10.2166/wst.2020.275 ◽

2020 ◽

Vol 81 (10) ◽

pp. 2176-2188

Author(s):

Zekun Yang ◽

Hailing Wang ◽

Huiming Sun ◽

Haifeng Tang ◽

Guangze Nie

Keyword(s):

Benzoic Acid ◽

Adsorption Capacity ◽

Selective Adsorption ◽

Exothermic Reaction ◽

Maximum Adsorption Capacity ◽

Gravimetric Analysis ◽

Order Kinetic ◽

Isothermal Adsorption ◽

Molecular Imprinted Polymers ◽

Imprinted Polymers

Abstract In order to reduce the environmental impact of benzoic acid (BA), molecular imprinted polymers based on attapulgite were facilely prepared by molecular imprinted technique. The samples were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermal gravimetric analysis. The adsorption performance, regeneration stability, and competitive selectivity of BA by benzoic acid-surface molecular imprinted polymers (BA-MIP) were systematically investigated by experiments. For this material, it has a high adsorption capacity of 41 mg/g and an equilibrium adsorption time of about 150 min. Compared with non-imprinted polymers, BA-MIP has a higher adsorption capacity for BA, and the dynamic adsorption behavior of BA by both of them conforms to the quasi-second-order kinetic model. The Langmuir adsorption isotherm equation was fitted the isothermal adsorption experiment. The thermodynamic analysis shows that the adsorption process is an exothermic reaction. The adsorption capacity of BA first increases and then decreases with an increase in pH, and the maximum adsorption capacity is reached at pH = 5. BA-MIP also has excellent selective adsorption capacity and regeneration stability for BA.

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Adsorption of Phosphate onto Slag from Aqueous Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.550-553.2255 ◽

2012 ◽

Vol 550-553 ◽

pp. 2255-2258

Author(s):

Bing Bing Liu ◽

Hua Yong Zhang ◽

Lu Yi Zhang

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Adsorption Process ◽

Freundlich Isotherm ◽

Langmuir Model ◽

Phosphate Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

High Adsorption ◽

Pseudo Second Order

Phosphate adsorption from aqueous solution using slag was investigated as the function of pH, contact time and adsorbent dosage. The results showed that the optimum value of pH was 2. Both Langmuir isotherm and Freundlich isotherm model were fit to describe the phosphate adsorption, and the maximum adsorption capacity from Langmuir model calculated was 9.09 mg/L. The adsorption process on slag followed pseudo second-order kinetic. Due to the relatively high adsorption capacity, the slag has the potential for application to removal phosphate from wastewater.

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Synthesis and Evaluation of the Ability of Poly(Methacrylic Acid-co-acrylamide)/nanoclay Composite Hydrogel in the Adsorption of Methylene Blue Dye

10.21203/rs.3.rs-1071501/v1 ◽

2021 ◽

Author(s):

Hamid Safarzadeh ◽

Seyed Jamaleddin Peighambardoust ◽

Seyed Hamed Mousavi ◽

Reza Mohammadi ◽

Rauf Foroutan ◽

...

Keyword(s):

Methylene Blue ◽

Adsorption Capacity ◽

Methacrylic Acid ◽

Adsorption Process ◽

Particle Diffusion ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Nanocomposite Hydrogel ◽

Cloisite 30B ◽

Intra Particle Diffusion

Abstract The performance of poly(methacrylic acid-co-acrylamide/nanoclay composite (poly(MAA-co-AAm)/NCC) hydrogel to adsorb methylene blue (MB) dye from aqueous solutions was investigated and the adsorption efficiency was improved by incorporating Cloisite 30B nanoclays in the adsorbent structure. The hydrogels were analyzed using FTIR, XRD, TGA, and SEM analysis. The effect of adsorbent dose, temperature, initial dye concentration, contact time, and pH on the efficiency of the adsorption process was investigated. Adsorption efficiencies of 98.57 and 97.65% were obtained for poly(MAA-co-AAm)/NCC and poly(MAA-co-AAm) hydrogels, respectively. Kinetic study revealed that the adsorption process followed pseudo-first-order kinetic model and α-parameter values of 6.558 and 1.113 mg/g.min were obtained for poly(MAA-co-AAm)/NCC and poly(MAA-co-AAm) hydrogels, respectively indicating a higher ability of nanocomposite hydrogel in adsorbing MB-dye. In addition, the results of the intra-particle diffusion model showed that various mechanisms such as intra-particle diffusion and liquid film penetration are important in the adsorption. The Gibbs free energy parameter of adsorption process showed negative values of -256.52 and -84.071 J/mol.K for poly(MAA-co-AAm)/NCC and poly(MAA-co-AAm) hydrogels indicating spontaneous nature of the adsorption. The results of enthalpy and entropy showed that the adsorption process was exothermic and random collisions were reduced during the adsorption. The equilibrium data for the adsorption process using poly(MAA-co-AAm)/NCC and poly(MAA-co-AAm) hydrogels followed Freundlich and Langmuir isotherm models, respectively. The maximum adsorption capacity values of 32.83 and 21.92 mg/g were obtained for poly(MAA-co-AAm)/NCC and poly(MAA-co-AAm) hydrogels, respectively. Higher adsorption capacity of nanocomposite hydrogel was attributed to the presence of Cloisite 30B clay nanoparticles in its structure. In addition, results of RL, n, and E parameters showed that the adsorption process was performed optimally and physically.

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U(VI) adsorption in water by sodium alginate modified Bacillus megaterium

Royal Society Open Science ◽

10.1098/rsos.202098 ◽

2021 ◽

Vol 8 (2) ◽

Author(s):

Dianxin Li ◽

Yiqing Yang ◽

Peng Zhang ◽

Jiangang Liu ◽

Tao Li ◽

...

Keyword(s):

Adsorption Capacity ◽

Sodium Alginate ◽

Bacillus Megaterium ◽

Adsorption Process ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

First Order ◽

First Order Kinetics ◽

Pseudo First Order

The surface of Bacillus megaterium was modified by coating sodium alginate. The modified B. megaterium before and after adsorption were characterized by SEM, FTIR and XPS. The effects of pH, reaction time, initial U(VI) concentration and adsorbent dosage on the adsorption of U(VI) by the modified B. megaterium were studied by batch adsorption experiments. The adsorption process was studied by pseudo-first-order kinetics and pseudo-second-order kinetic models, Langmuir and Freundlich isotherms. The results showed that the maximum adsorption capacity of U(VI) was 74.61 mg g −1 under the conditions of pH 5.0, adsorbent 0.2 g l −1 , 30°C and initial U(VI) concentration of 15 mg l −1 . The adsorption process accords with pseudo-first-order kinetics and Langmuir isotherm. The adsorption capacity of U(VI) by the modified B. megaterium was still higher than 80% after five times of desorption and reuse experiments. In conclusion, the sodium alginate modified B. megaterium was an ideal material for U(VI) biosorption.

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