Selective Adsorption of CR (VI) onto Amine-Modified Passion Fruit Peel Biosorbent

This study aimed to prepare surface amino-riched passion fruit peel (DAPFP) by amination reaction with low-cost biomaterials and use it as a biosorbent to adsorb Cr (VI). The specific physicochemical and structural properties of DAPFP were characterized by SEM, EDS, XRD, TG, Zeta, XPS, and FT-IR. The effects of pH value, initial concentration, adsorption time, coexisting ions, and temperature on the adsorption of Cr (VI) were systematically investigated. The results showed that within 90 min, DAPFP could reduce the concentration of Cr (VI) solution (1 mg/L−1) to an allowable safe level of drinking water (0.05 mg/L−1) specified by the World Health Organization. The adsorption process complies with pseudo-second-order kinetics and the Langmuir isotherm model. The adsorption capacity of the prepared biosorbent could reach 675.65 mg/g−1. The results of thermodynamic studies confirmed that the adsorption process was a self-discharging heat process. DAPFP also showed good reusability; even after being used repeatedly five times, it still showed excellent adsorption performance. FT-IR and XPS analyses showed that electrostatic attraction and reduction were the main reasons for the adsorption. By virtue of its low cost and excellent adsorption performance, DAPFP has a potential practical application as an adsorbent in treating Cr (VI) containing wastewater.

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Super and Selective Adsorption of Cationic Dyes onto Carboxylate-Modified Passion Fruit Peel Biosorbent

Frontiers in Chemistry ◽

10.3389/fchem.2021.646492 ◽

2021 ◽

Vol 9 ◽

Author(s):

Kaiwei Chen ◽

Linlin Du ◽

Peng Gao ◽

Junli Zheng ◽

Yuanli Liu ◽

...

Keyword(s):

Adsorption Process ◽

Selective Adsorption ◽

Low Cost ◽

Methyl Violet ◽

Passion Fruit ◽

Cationic Dyes ◽

Polluted Water ◽

Isotherm Models ◽

Fruit Peel ◽

Environmental Friendliness

The carboxylate-functionalized passion fruit peel (PFPCS) was an efficient and rapid biosorbent for wastewater treatment. The PFPCS exhibited excellent selectivity to the cationic dyes, where the maximum adsorption capacities for methylene blue (MB) and methyl violet (MV) were 1,775.76 mg g−1 and 3,756.33 mg g−1, respectively. And the adsorption process of MB and MV on PFPCS reached equilibrium within 20 min. Moreover, the adsorption conditions and mechanisms were investigated. The adsorption process was in good agreement with the pseudo-second-order and Langmuir isotherm models. The adsorption mechanism was also proposed to be electrostatic interaction and hydrogen bond. After six cycles of desorption-adsorption, the removal efficient of MB and MV could be kept above 95%. Thus, PFPCS was considered as a highly efficient absorbent for removing cationic dyes from polluted water due to excellent adsorption characteristics, low cost and environmental friendliness.

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Removal of Cadmium(II) from Water using Modified Citrus limettioides Peels: Thermodynamic and Isotherm Studies

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22278 ◽

2019 ◽

Vol 32 (1) ◽

pp. 73-78

Author(s):

P. Janaki ◽

R. Sudha ◽

T.S. Sribharathi ◽

P. Anitha ◽

K. Poornima ◽

...

Keyword(s):

Adsorption Process ◽

Low Cost ◽

Raw Material ◽

Isotherm Models ◽

Batch Adsorption ◽

Adsorption Method ◽

Chemically Modified ◽

Adsorption Performance ◽

Monolayer Adsorption ◽

Isotherm Equations

The adsorption performance of sulphuric acid treated low cost adsorbent synthesized by using Citrus limettioides peel as an effective raw material for the removal of cadmium(II) from water. The batch adsorption method was carried out to optimize some parameters like contact time, pH and adsorbent dose. The nonlinear isotherm equations were used to calculate the different isotherm constant of five isotherm models namely Freundlich, Langmuir, Dubinin-Radushkevich, Redlich-Peterson and Sips. The Langmuir monolayer adsorption capacity of chemically modified Citrus limettioides peel was found to be 287.60 mg g-1. The negative values of ΔGº and ΔHº showed that the adsorption process is spontaneous and exothermic.

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Luteolin Imprinted Polymer with Selective Recognition and Adsorption Performance

Materials Science Forum ◽

10.4028/www.scientific.net/msf.809-810.297 ◽

2014 ◽

Vol 809-810 ◽

pp. 297-301

Author(s):

Ping Rui Meng ◽

Liang Bo Li

Keyword(s):

Adsorption Process ◽

Selective Adsorption ◽

Methanol Solution ◽

Selective Recognition ◽

Imprinted Polymer ◽

Molecular Imprinted Polymers ◽

Adsorption Dynamics ◽

Adsorption Performance ◽

Recognition Specificity ◽

Adsorption Amount

In order to selectively separate luteolin from its crude solution, we synthesized luteolin molecular imprinted polymers (LMIP) with high recognition specificity for luteolin, using an imprinting technique. Luteolin was used as template, methanol as solvent, and N,N’-methylenebisacrylamide (MBAA) as the cross-linking. Then prepared LMIP were characterized and evaluated by scanning electron microscope (SEM) and equilibrium absorption experiments. The results showed that the cavities matching with the template molecules in size and structure were present in the LMIP. Adsorption dynamics analysis suggested that, when the adsorption time reached 4 h, the adsorption process had reached balance and the adsorption capacity was at steady state. The selective adsorption amount reached at 35.65 umol/g for the LMIP, while a lower value of 11.68 umol/g for the blank polymer (i.e. nontemplated). Relative to the corresponding blank polymer, LMIP had an excellent recognition to luteolin in methanol solution. Keywords: Molecular imprinting, Molecular recognition, Adsorbent, Luteolin

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Synthesis Fe3O4/Talc nanocomposite by coprecipition-ultrasonication method and advances in hexavalent chromium removal from aqueous solution

Adsorption Science & Technology ◽

10.1177/0263617420969112 ◽

2020 ◽

Vol 38 (9-10) ◽

pp. 483-501

Author(s):

Nguyen Thi Huong ◽

Nguyen Ngoc Son ◽

Vo Hoang Phuong ◽

Cong Tien Dung ◽

Pham Thi Mai Huong ◽

...

Keyword(s):

Aqueous Solution ◽

Adsorption Process ◽

Low Cost ◽

Batch Experiments ◽

X Ray Diffraction ◽

Order Model ◽

X Ray ◽

Pseudo Second Order ◽

Ft Ir ◽

Langmuir And Freundlich Equations

The Fe3O4/Talc nanocomposite was synthesized by the coprecipitation-ultrasonication method. The reaction was carried out under a inert gas environment. The nanoparticles were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), fourier-transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry techniques (VSM), the surface area of the nanoparticles was determined to be 77.92 m2/g by Brunauer-Emmett-Teller method (BET). The kinetic data showed that the adsorption process fitted with the pseudo-second order model. Batch experiments were carried out to determine the adsorption kinetics and mechanisms of Cr(VI) by Fe3O4/Talc nanocomposite. The adsorption process was found to be highly pH-dependent, which made the material selectively adsorb these metals from aqueous solution. The isotherms of adsorption were also studied using Langmuir and Freundlich equations in linear forms. It is found that the Langmuir equation showed better linear correlation with the experimental data than the Freundlich. The thermodynamics of Cr(VI) adsorption onto the Fe3O4/Talc nanocomposite indicated that the adsorption was exothermic. The reusability study has proven that Fe3O4/Talc nanocomposite can be employed as a low-cost and easy to separate.

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Comparative MCDM Analysis for AMD Treatment Method Selection

10.21203/rs.3.rs-501642/v1 ◽

2021 ◽

Author(s):

Zoran Štirbanović ◽

Vojka Gardić ◽

Dragiša Stanujkić ◽

Radmila Marković ◽

Jovica Sokolović ◽

...

Keyword(s):

Ion Exchange ◽

Metal Ions ◽

Adsorption Process ◽

Mine Drainage ◽

Ph Value ◽

Low Cost ◽

Treatment Method ◽

Passive Treatment ◽

Copper Production ◽

Capital Costs

Abstract Robule Lake is located in Eastern Serbia, near city of Bor, known for copper production, and it is being influenced by waste materials from mining activities. For the purification of water from Robule Lake, contaminated with various metal ions (Fe, Cu, Zn, Mn, Cd, Ni, etc.), acid mine drainage (AMD) treatment methods such as: passive treatment method, sequential neutralization, ion exchange, adsorption process based on low cost adsorbents, adsorption process based on natural zeolits, electrodialysis, filtration with nanofiltration membranes, and reverse osmosis, were evaluated by following MCDM methods: TOPSIS, VIKOR, MOOSRA; WASPAS, and CoCoSo. Criteria used for the evaluation were: efficiency in the metal ions removal and the quality of the purified water, necessity of pre-treatment and / or post-treatment of treated water, possibility of using the generated waste, capital costs, operating and maintenance costs, needed area, and sensitivity of the method. The results of the MCDM analysis showed that sequential neutralization was the most appropriate for this wastewater, while passive treatment system and ion exchange were ranked as second and third, respectively.After the selection of AMD treatment method, neutralization tests with lime were carried out on the water sample from Robule Lake. The results of sequential neutralization testing showed that concentration of Fe ions could be lowered below the maximal allowable concentration prescribed by Serbian legislation at pH value 4. The other metal ions: Cu, Zn, and Ni needed pH value 7, and Mn and Cd needed pH 10 for effective removal.

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Adsorption Performance for Ag(І) of an Ethoxycarbonyl Thiourea Chelating Resin

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.1077 ◽

2011 ◽

Vol 311-313 ◽

pp. 1077-1080 ◽

Cited By ~ 1

Author(s):

Shuai Wang ◽

Jing Jing Xiao ◽

Hong Zhong ◽

Gang Zhao ◽

Yan Long Wen

Keyword(s):

Adsorption Process ◽

Langmuir Equation ◽

Chelating Resin ◽

Maximum Adsorption Capacity ◽

Adsorption Enthalpy ◽

Adsorption Performance ◽

Adsorption Capacities ◽

Adsorption Temperature ◽

Endothermic Process ◽

Ft Ir

Effects of initial concentration of Ag(І), concentration of HNO3, contact time and adsorption temperature on adsorption capacities of a novel polystyrene modified ethoxycarbonyl thiourea resin were investigated, and the maximum adsorption capacity of Ag(І) reached 4.11 mmol·g-1. The adsorption kinetics was well fitted Boyd’s diffusion equation of liq·uid film, so the adsorption was controlled by liquid film diffusion. The experimental date fitted Langmuir equation, and the correlation coefficient was close to 1. The positive value of adsorption enthalpy ΔH is indicative of an endothermic process. FT-IR characteristic peaks of ethoxycarbonyl and thiourea groups changed obviously fore-and-aft adsorption, which means that the corresponding functional groups coordinate with Ag during the adsorption process.

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Experimental study on phosphate rock modified soil-bentonite as cut-off wall materials

Water Science & Technology Water Supply ◽

10.2166/ws.2021.320 ◽

2021 ◽

Author(s):

Yuheng Li ◽

Xing Zeng ◽

Zhi Lin ◽

Jia Su ◽

Tong Gao ◽

...

Keyword(s):

Phosphate Rock ◽

Adsorption Process ◽

Exothermic Reaction ◽

X Ray Diffraction ◽

Microscopic Mechanism ◽

Isothermal Adsorption ◽

Adsorption Performance ◽

Batch Tests ◽

Ft Ir ◽

Modified Soil

Abstract The phosphate rock has great potential value in the application of cut-off walls for heavy metal contaminated sites. The effects of initial concentration of Pb2+, contact time, temperature and pH on the adsorption performance of phosphate rock modified soil-bentonite (PSB) were analyzed by Batch tests, also the microstructure and physicochemical properties of the adsorbent were characterized and analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The results showed that the incorporation of phosphate rock improves the adsorption performance of the mixed material for Pb2+ in acidic environment, and the maximum adsorption amount of PSB can be 154% greater than that of soil-bentonite (SB). The kinetic analysis showed that intraparticle diffusion and liquid film diffusion participate in control of the adsorption process at the same time, and the Langmuir model could fit the isothermal adsorption data better. The adsorption process of PSB to Pb2+ is an exothermic reaction process, and the low temperature environment is beneficial to the adsorption of Pb2+. Studies on the microscopic mechanism show that the PO43− react with Pb2+ in the solution to form phosphate precipitation, and –OH and PO43− on the surface or interlayer of the adsorbent participate in the adsorption process of Pb2+.

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Production of Xanthan Gum by Xanthomonas Campestris CCT 13951 Submerged Fermentation on hydrolysed agroindustrial by-products

10.21203/rs.3.rs-158198/v1 ◽

2021 ◽

Author(s):

Joice Correia Santos ◽

Diego de Freitas Coêlho ◽

Elias Basile Tambourgi ◽

Gabriel Francisco Da Silva ◽

Roberto Rodrigues Souza

Keyword(s):

Xanthan Gum ◽

Xanthomonas Campestris ◽

Cheese Whey ◽

Low Cost ◽

Cost Effective ◽

Industrial Applications ◽

Passion Fruit ◽

Strong Impact ◽

Fruit Peel ◽

Acid Hydrolysate

Abstract Xanthan is a natural polymer often obtained through fermentative processes using Xanthomonas, which remarkable properties - including biocompatibility, biodegradability, and non-toxicity – fit a myriad of industrial applications. The aim of this study was to evaluate the influence of different alternative fermentable substrates derived from agro-industrial waste (cheese whey and passion fruit peel), the production and rheological properties of the gum. The fermented substrate composition had a strong impact on production (8.15–14.81 g∙L-1) and apparent viscosity (31.9–510 mPa.s). The maximum xanthan gum production was observed after 72 h using cheese whey and passion fruit peel acid hydrolysate supplemented with K2HPO4 (AH:W – Phosphate). However, the maximum viscosity was found for medium without supplementation (AH:W), twice the value of the samples supplemented with phosphate. All solutions were highly pseudoplastic. This study provides a cost-effective solution for the reusing of cheese whey and passion fruit peel and possible low-cost approach for xanthan production. .

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In Situ Preparation of Novel Porous Nanocomposite Hydrogel as Effective Adsorbent for the Removal of Cationic Dyes from Polluted Water

Polymers ◽

10.3390/polym12123002 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3002 ◽

Cited By ~ 1

Author(s):

Badr M. Thamer ◽

Ali Aldalbahi ◽

Meera Moydeen A. ◽

Mohamed H. El-Newehy

Keyword(s):

Linear Models ◽

Adsorption Process ◽

Ph Value ◽

Low Cost ◽

Freundlich Isotherm ◽

Polymerization Process ◽

Polluted Water ◽

Swelling Properties ◽

Hydrogel Nanocomposite

The use of some hydrogels as adsorbents for pollutants removal from wastewater is limited due to their high swelling properties and the difficulty in recovering them after the adsorption process. To overcome these problems, a new hydrogel nanocomposite based on chitosan-grafted-polyacrylic acid/oxidized electrospun carbon nanofibers (CT-g-PAA/O-ECNFs) was prepared by an in situ grafting polymerization process. The prepared hydrogel nanocomposite was used as a novel effective and highly reusable adsorbent for the removal of methylene blue (MB) from polluted water with low cost. The morphology and the structure of CT-g-PAA/O-ECNFs were investigated by numerous techniques. The effect of incorporating O-ECNFs on the swelling capability of the prepared hydrogel was explored in distillated water and MB solution at normal pH. The effect of parameters including ratio of O-ECNFs, contact time, pH, initial concentration, and temperature on adsorption process were explored. The adsorption isotherm and kinetic were studied by numerous non-linear models. The obtained results confirmed that the incorporation of O-ECNFs into the hydrogel network decreased the swelling capacity and improved its ability towards MB dye removal. The adsorption process depended on the pH value of the dye solution. Additionally, the adsorption and kinetic results were fitted using the Freundlich isotherm model and pseudo second order model (PSO), respectively. Moreover, the new adsorbents can be recycled for at least five cycles keeping its adsorption capacity and can be easily recovered without loss in its initial weight.

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Removal of Hg2+ From Desulfurization Wastewater By Tannin-Immobilized Graphene Oxide

10.21203/rs.3.rs-599443/v1 ◽

2021 ◽

Author(s):

Heng Chen ◽

Fengjun Liu ◽

Chenjian Cai ◽

Hao Wu ◽

Linjun Yang

Keyword(s):

Graphene Oxide ◽

Functional Groups ◽

Removal Efficiency ◽

Economic Benefit ◽

Adsorption Process ◽

Ph Value ◽

Low Cost ◽

Order Kinetic ◽

Chelation Reaction ◽

Desulfurization Wastewater

Abstract A novel adsorbent by immobilizing tannic acid (TA) on graphene oxide (GO) was proposed and used to remove Hg2+ from desulfurization wastewater. The morphology and physic-chemical property of tannin-immobilized graphene oxide (TAIGO) was characterized by Scanning electron microscopy (SEM), Atomic Force Microscope (AFM), and Fourier transform infrared spectroscopy (FTIR). The characterization results showed that the TA was immobilized on the GO successfully, and new functional groups were introduced on TAIGO. The effect of contact time, adsorbent dose, pH, and ion components on removal efficiency were evaluated. It was found that the adsorption process would complete within 15 min, and a higher removal efficiency could be obtained on the increased adsorbent dosage. The pH value would affect the protonation process of TAIGO and the form of Hg2+ in the wastewater. The high-concertation Cl- and SO32- would hinder the absorption performance, while SO42- and cations had a negligible impact. Besides, an excellent economic benefit of TAIGO was achieved in the regeneration performance evaluation experiment, and removal efficiency of was 88% remained after three recycles. Most importantly, the TAIGO exhibited a better adsorption performance and economic benefit than GO and TA. The adsorption process was fitted with the pseudo-second-order kinetic model(R=0.9995), and the adsorption of TAIGO for Hg2+ was mainly relies on the functional groups on GO and the chelation reaction between TA and Hg2+. These facts indicated that the TAIGO was a low-cost and high removal of Hg2+ efficiency adsorbent, which could be further used in the practical desulfurization wastewater.

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