Iron-Loaded Pomegranate Peel as a Bio-Adsorbent for Phosphate Removal

This study investigated the adsorption of phosphate from aqueous solutions using pomegranate peel (PP) as a bio-adsorbent. For this purpose, PP was activated via saponification using sodium hydroxide (NaOH) followed by cationization using iron chloride (FeCl3). The iron-loaded PP (IL-PP) was characterized using zeta potential measurement, scanning electron microscopy, and Fourier transform infrared analysis. The batch adsorption method was followed to determine the equilibrium time and effect of pH on the adsorption process. The full factorial design methodology was used to analyze the effects of influencing parameters and their interactions. The effective removal of phosphate up to 90% was achieved within 60 min, at pH 9 and 25 °C temperature using a 150 mg dose of IL-PP. A non-linear method was used for the modeling of isotherm and kinetics. The results showed that the kinetics is best fitted to the Elovich model (R2 = 0.97), which assumes the dominance of the chemisorption mechanism, whereas the isotherm obeys both Langmuir (R2 = 0.98) and Freundlich (R2 = 0.94) models with a maximum phosphate uptake of 49.12 mg·g−1. Investigation of thermodynamic parameters indicated the spontaneity and endothermic nature of the process. These results introduce IL-PP as an efficient bio-adsorbent of phosphate.

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Removal of phosphate from aqueous solution by chitosan coated and lanthanum loaded biochar derived from urban dewatered sewage sludge: adsorption mechanism and application to lab scale columns

Water Science & Technology ◽

10.2166/wst.2021.485 ◽

2021 ◽

Author(s):

Xiaoling Zhang ◽

Xincong Liu ◽

Zhuo Zhang ◽

Ziwei Chen

Keyword(s):

Freundlich Isotherm ◽

Breakthrough Curves ◽

Phosphate Removal ◽

Phosphate Adsorption ◽

Infrared Analysis ◽

Batch Adsorption ◽

Adsorption Parameters ◽

X Ray ◽

Adsorption Mechanisms ◽

Adsorption Kinetics And Isotherm

Abstract A lanthanum modified sludge biochar chitosan (La-SBC-CS) microsphere was successfully synthesized by dropping sludge biochar (BC) and chitosan into an Lanthanum chloride solution. Batch adsorption experiments were conducted to investigate the adsorption kinetics and isotherm. Application of continuous phosphate removal was achieved via lab-scale column reactors. The phosphate adsorption equilibrium data of the La-SBC-CS fitted well with the Freundlich isotherm, with a maximum adsorption amount of 81.54 mg p/g at 25 °C. Characterization of the adsorbent using scanning electron microscopy analysis (SEM), X ray energy spectrum analysis (EDS), X-ray diffraction analysis (XRD) and Fourier infrared analysis (FTIR) techniques suggested that the possible adsorption mechanisms were electrostatic interaction, ligand exchange and complexation. The La-SBC-CS kept 76.37% phosphate removal efficiency after eight recycles. The results of continuous column reactor experiment demonstrated that the breakthrough time increased with an increase in adsorbents filling height, while it decreased with an increase in initial phosphate concentration or flow velocity. YOON model was applied to the continuous experimental data to predict breakthrough curves and determined the characteristic adsorption parameters for process design. This study indicated that the potential for the practical application of La-SBC-CS in phosphate removal from wastewater.

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Release of toxic methylene blue from water by mesoporous silicalite-1: characterization, kinetics and isotherm studies

Applied Water Science ◽

10.1007/s13201-021-01435-z ◽

2021 ◽

Vol 11 (7) ◽

Author(s):

Sabarish Radoor ◽

Jasila Karayil ◽

Aswathy Jayakumar ◽

Jyotishkumar Parameswaranpillai ◽

Suchart Siengchin

Keyword(s):

Electron Microscopy ◽

Contact Time ◽

Dye Removal ◽

Batch Adsorption ◽

Aqueous Environment ◽

Order Kinetic ◽

Adsorption Method ◽

X Ray ◽

Ft Ir ◽

Adsorption Desorption

AbstractIn the present work, we have developed a mesoporous silicalite-1 using CMC as a template for the removal of MB from aqueous solution. The synthesized silicalite-1 were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Energy-dispersive X-ray spectroscopy (EDAX) and N2 adsorption–desorption isotherm (BET). XRD and FT-IR analysis confirmed the formation of crystallinity and development of MFI structure in the mesoporous silicalite-1. The adsorption of MB dye on mesoporous silicalite-1 was conducted by batch adsorption method. The effect of various parameters such as adsorbent dosage, initial dye concentration, contact time and temperature on the dye uptake ability of silicalite-1 was investigated. The operating parameters for the maximum adsorption are silicalite-1 dosage (0.1 wt%), contact time (240 min), initial dye concentration (10 ppm) and temperature (30 ℃). The MB dye removal onto mesoporous silicalite-1 followed pseudo-second-order kinetic and Freundlich isotherm. The silicalite-1 exhibits 86% removal efficiency even after six adsorption–desorption cycle. Therefore, the developed mesoporous silicalite-1 is an effective eco-friendly adsorbent for MB dye removal from aqueous environment.

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Adsorptive Removal of Phosphate from Aqueous Solutions Using Low-Cost Volcanic Rocks: Kinetics and Equilibrium Approaches

Materials ◽

10.3390/ma14051312 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1312

Author(s):

Dereje Tadesse Mekonnen ◽

Esayas Alemayehu ◽

Bernd Lennartz

Keyword(s):

Aqueous Solutions ◽

Low Income ◽

Low Cost ◽

Volcanic Rocks ◽

Phosphate Removal ◽

Phosphate Adsorption ◽

Adsorptive Capacity ◽

Batch Adsorption ◽

Order Kinetic ◽

Adsorptive Removal

The contamination of surface and groundwater with phosphate originating from industrial and household wastewater remains a serious environmental issue in low-income countries. Herein, phosphate removal from aqueous solutions was studied using low-cost volcanic rocks such as pumice (VPum) and scoria (VSco), obtained from the Ethiopian Great Rift Valley. Batch adsorption experiments were conducted using phosphate solutions with concentrations of 0.5 to 25 mg·L−1 to examine the adsorption kinetic as well as equilibrium conditions. The experimental adsorption data were tested by employing various equilibrium adsorption models, and the Freundlich and Dubinin-Radushkevich (D-R) isotherms best depicted the observations. The maximum phosphate adsorption capacities of VPum and VSco were calculated and found to be 294 mg·kg−1 and 169 mg·kg−1, respectively. A pseudo-second-order kinetic model best described the experimental data with a coefficient of correlation of R2 > 0.99 for both VPum and VSco; however, VPum showed a slightly better selectivity for phosphate removal than VSco. The presence of competitive anions markedly reduced the removal efficiency of phosphate from the aqueous solution. The adsorptive removal of phosphate was affected by competitive anions in the order: HCO3− >F− > SO4−2 > NO3− > Cl− for VPum and HCO3− > F− > Cl− > SO4−2 > NO3− for VSco. The results indicate that the readily available volcanic rocks have a good adsorptive capacity for phosphate and shall be considered in future studies as test materials for phosphate removal from water in technical-scale experiments.

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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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Microwave Enhanced Synthesis of Sulfonated Chitosan-montmorillonite for Effective Removal of Methylene Blue

10.21203/rs.3.rs-262124/v1 ◽

2021 ◽

Author(s):

Nur Shazwani Abdul Mubarak ◽

N.N. Bahrudin ◽

Ali H. Jawad ◽

B.H. Hameed ◽

Sumiyyah Sabar

Keyword(s):

Methylene Blue ◽

Langmuir Isotherm ◽

Cationic Dyes ◽

Isotherm Model ◽

Batch Adsorption ◽

Sulfonate Group ◽

Order Kinetic ◽

Effective Removal ◽

Langmuir Isotherm Model ◽

Mb Adsorption

Abstract In this work, sulfonated chitosan montmorillonite composite (S-CS-MT) beads were synthesized using a microwave irradiation method designed to have a better saving-time procedure. The potency of S-CS-MT as an adsorbent was assessed for the removal of cationic dyes such as methylene blue (MB) from aqueous solution. The batch adsorption experiments indicated that MB adsorption onto S-CS-MT follows the Pseudo-second-order kinetic and Langmuir isotherm model. The maximum extent obtained from the Langmuir isotherm model for MB adsorption was 188.2 mg g− 1 at 303 K. The thermodynamic study indicated that the adsorption reaction is favorable and spontaneous. These findings indicated that montmorillonite chitosan grafted with the sulfonate group has the ability and efficacy as biohybrid adsorbent for the adsorption of cationic dyes.

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Removal of Dyes from Wastewater of Artisanal Dyeing Plants by Adsorption in a Fixed Bed Column of Deactivated Lichens

International Research Journal of Pure and Applied Chemistry ◽

10.9734/irjpac/2021/v22i530405 ◽

2021 ◽

pp. 1-11

Author(s):

Kouassi Kouadio Dobi-Brice ◽

Yacouba Zoungranan ◽

Dje Daniel Yannick ◽

Ekou Lynda ◽

Ekou Tchirioua

Keyword(s):

Ivory Coast ◽

Fixed Bed ◽

Batch Adsorption ◽

Real Problem ◽

Adsorption Method ◽

Fixed Bed Column ◽

Good Efficiency ◽

Continuous Adsorption ◽

Column Adsorption ◽

Study Laboratory

Aims: Pollution by wastewaters from various urban activities such as artisanal dyeing plants is a real problem for developing countries. The treatment of wastewater by the adsorption method is carried out by means of less expensive and available adsorbent media. Two techniques of the adsorption method are possible: adsorption in continuous mode (column adsorption) and adsorption in discontinuous mode (batch adsorption). The choice of the continuous adsorption technique is justified by its ability to process large volumes of solutions. In this study, dyes contained in wastewater from artisanal dyeing plants were removed by continuous adsorption in a fixed-bed column of deactivated lichen biomass (Parmotrema dilatatum). Study Design: Random design Place and Duration of Study: Laboratory of Thermodynamics and Environmental Physico-Chemistry (University Nangui Abrogoua, Ivory Coast) between May 2020 and October 2020. Methodology: Four (4) categories of wastewater were collected in artisanal cotton and leather dyeing plants through two municipalities of the city of Abidjan, economic capital of Ivory Coast. Two (2) wastewaters colored in blue from dyeing of cotton boubous and jeans and two (2) wastewaters colored in red from dyeing of leather jackets and bags. These wastewaters were treated through the fixed bed column of deactivated lichens. The column feed rate was set at 0, 07 L.min-1 and the adsorbent bed mass at 100 g. Results: The study showed that, regardless of the nature of the dyed object and regardless of the target dye, the amount of dye adsorbed was better with waters of higher initial concentration. Thus the best amount of adsorbed dye is 44.444 mg.g-1 and the best removal rate is 97.9%. These values are obtained with the red wastewater of bags (RWB) treatment which was the most concentrated wastewater. Conclusion: Good efficiency of deactivated lichen bed as adsorbent for the in situ removal of dyes from wastewater by continuous adsorption.

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Utilization of Waste Leather Powders for Highly Effective Removal of Dyes from Water

Polymers ◽

10.3390/polym11111786 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1786 ◽

Cited By ~ 8

Author(s):

Liangjun Xia ◽

Chen Li ◽

Sijie Zhou ◽

Zhuan Fu ◽

Yun Wang ◽

...

Keyword(s):

Low Cost ◽

Dye Adsorption ◽

Reactive Dyes ◽

Infrared Analysis ◽

Leather Industry ◽

Textile Materials ◽

Effective Removal ◽

Highly Effective ◽

Equilibrium And Kinetics ◽

Pseudo Second Order

As a natural polymer, leather and its associated industries are known to be the leading economic sector in many countries. However, the huge amounts of leather waste generated from the leather industry causes severe environmental pollution. Herein, cow leather (CL) powders were prepared using a homemade machine and used as a low-cost adsorbent for the effective removal of reactive dyes from wastewater. The as-prepared CL powders exhibited dot-like, rod-like, and fiber-like morphologies. A Fourier transform infrared analysis and an x-ray diffraction analysis demonstrated that the CL powders retained the main structure of the protein contained in it. In addition, an improvement in thermal stability was also observed for the CL powders. Dye adsorption experiments indicate that the CL powders showed the highly effective removal of C.I. Reactive Red 120 (RR120), C.I. Reactive Yellow 127 (RY127), and C.I. Reactive Blue 222 (RB222) with the adsorption capacity of 167.0, 178.9, and 129.6 mg·g−1, respectively. The Langmuir, pseudo-second order, and intraparticle diffusion models could well depict the adsorption equilibrium and kinetics of CL powders toward the investigated reactive dyes. The as-prepared CL powders can be used as a potential adsorbent in the treatment of dye contaminated wastewater. Future studies will mainly focus on the application of the adsorbed CL powders for the pigment printing of textile materials.

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Synthesis of Modified Chitosan with Thiamine Hydrochloride as the Adsorbent for Calcium (II) Ion Removal

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.798.397 ◽

2019 ◽

Vol 798 ◽

pp. 397-403

Author(s):

Ratana Sananmuang

Keyword(s):

Calcium Ions ◽

Water Hardness ◽

Batch Adsorption ◽

Thiamine Hydrochloride ◽

Modified Chitosan ◽

Ion Removal ◽

Effective Removal ◽

Optimum Ph ◽

Langmuir Isotherm Model ◽

Nmr Techniques

Water quality is very important to food processing industry. Water hardness caused by calcium ions in water can affect the properties of food including aroma, texture, flavor and appearance. Chitosan has amino functional groups that can remove metal ions from aqueous solution. However, chitosan can give more effective removal of calcium ions if it is modified with functionalized substance such as thiamine hydrochloride. therefore, the objectives of this study were to synthesize the modified chitosan with thiamine hydrochloride (MCTH) and to determine its efficiency for removal of calcium ion in solution. Chitosan was prepared from crab shells and modified with thiamine hydrochloride at 30 °C. The morphology of both crab-shell chitosan (CSC) and MCTH was characterized by SEM, FTIR and NMR techniques. Batch adsorption experiments were conducted as a function of pH, contacted time and initial concentration of calcium (II) ions. The desorption of calcium(II) ion from both adsorbents was also investigated. The concentration of calcium in solution was measured by FAAS technique. The results indicated that the optimum pH for adsorption was 6.0 for both CSC and MCTH. The adsorption capacity for MCTH (48.31 mg g-1) was greater than that of CSC (1.52 mg g-1). The isotherm showed that the adsorption process of calcium (II) ions onto MCTH was fitted to Langmuir isotherm model. Calcium desorption from MCTH was lower than that of CSC.

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Adsorption characteristics of atrazine on different soils in the presence of Cd(II)

Adsorption Science & Technology ◽

10.1177/0263617420928845 ◽

2020 ◽

Vol 38 (7-8) ◽

pp. 225-239 ◽

Cited By ~ 1

Author(s):

Sun Jing ◽

Ma Xiu Lan ◽

Wang Wen ◽

Zhang Jing ◽

Zhang Hao ◽

...

Keyword(s):

Clay Content ◽

Cadmium Stress ◽

Black Soil ◽

Batch Adsorption ◽

Alkaline Soil ◽

Order Kinetic ◽

Adsorption Method ◽

Weakly Alkaline ◽

Adsorption Characteristics ◽

Albic Soil

In this study, the effects of temperature, pH, and biochar under cadmium stress on the adsorption characteristics of atrazine in soils in northeast China were studied by batch adsorption method. In the atrazine–Cd(II) coexistence system, the adsorption of atrazine by the soils reached equilibrium within 24 h, but there were some differences in sorption capacities of the three types of soil and the order of adsorption is albic soil > black soil > saline-alkaline soil. With the concentration of atrazine increased, the adsorption capacity of atrazine in the three types of soil gradually increased, the upward trend became more obvious with the ambient temperature of the solution decreased. The adsorption kinetics curves of atrazine in the three types of soil conform to the pseudo-second-order kinetic model and the adsorption isotherm follows the Langmuir model. When atrazine and Cd(II) coexist in soils, the decrease in atrazine adsorption in the soil may be due to the competitive interaction between the two chemicals. Cd(II) occupies part of the adsorption site of atrazine, thus saturating the active site in soils. Since atrazine is a weakly alkaline pesticide, the lower the pH of the soil, the higher the affinity of atrazine for the soil. After adding biochar to the soil, the functional groups in biochar can form π bond with atrazine, which promotes the fixation of atrazine in the soil. The results show that the prevention of atrazine and cadmium leaching can be achieved by appropriately adjusting the pH, temperature, clay content, and organic matter of the soils.

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Effect of ageing on surface charge characteristics and adsorption behaviour of cadmium and arsenate in two contrasting soils amended with biochar

Soil Research ◽

10.1071/sr13187 ◽

2014 ◽

Vol 52 (2) ◽

pp. 155 ◽

Cited By ~ 27

Author(s):

Chamali Laksala Nagodavithane ◽

Balwant Singh ◽

Yunying Fang

Keyword(s):

Surface Charge ◽

Contaminated Soils ◽

Negative Charge ◽

Exchange Capacity ◽

Batch Adsorption ◽

Adsorption Behaviour ◽

Solution Ph ◽

Adsorption Method ◽

Adsorption Processes ◽

Anionic Species

Biochar has been recognised as an effective amendment for the remediation of contaminated soils; however, there is limited knowledge on the effects of biochar ageing in soil on its adsorption behaviour for cationic and anionic species. Biochars are considered to develop negative charge from oxidation with ageing, which may create additional interaction mechanisms for adsorption processes. In the present study, surface charge characteristics and cadmium (Cd) and arsenate (AsO43–) adsorption behaviour of aged biochar were investigated in two soils with variable charge, an Oxisol and an Inceptisol, by comparing (i) unamended soils, and soils amended with (ii) fresh biochar (450°C) and (iii) biochar (450°C) aged for 12 months, applied at a rate of 2% w/w. Surface charge characteristics were assessed using the ‘index’ ion adsorption method, with a LiCl electrolyte. Batch adsorption studies were conducted using fresh and aged soil–biochar mixtures. In contrast to previous studies, the results provided no evidence of an increase in cation exchange capacity as a consequence of biochar ageing. There was an increase in Cd adsorption in the presence of aged biochar in both soil types compared with unamended soils and soils amended with fresh biochar. Results also indicated an increase in AsO43– adsorption in the Inceptisol amended with aged biochar, whereas a decrease in AsO43– adsorption was observed in the Oxisol amended with aged biochar. Overall, the study has highlighted that adsorption behaviour of aged biochar varies depending on the ion it interacts with, soil properties and solution pH.

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