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

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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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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Performance and adsorption mechanism of a magnetic calcium silicate hydrate composite for phosphate removal and recovery

Water Science & Technology ◽

10.2166/wst.2018.184 ◽

2018 ◽

Vol 2017 (2) ◽

pp. 578-591 ◽

Cited By ~ 1

Author(s):

Lihong Peng ◽

Hongliang Dai ◽

Yifeng Wu ◽

Zheqin Dai ◽

Xiang Li ◽

...

Keyword(s):

Electron Microscopy ◽

Magnetic Separation ◽

Adsorption Kinetics ◽

Calcium Silicate ◽

Calcium Silicate Hydrate ◽

Phosphate Removal ◽

Separation Technique ◽

Phosphate Adsorption ◽

X Ray ◽

Removal And Recovery

Abstract A novel magnetic calcium silicate hydrate composite (Fe3O4@CSH) was proposed for phosphorus (P) removal and recovery from a synthetic phosphate solution, facilitated by a magnetic separation technique. The Fe3O4@CSH material was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), zeta-potential and magnetic curves. The chemical composition and structure of Fe3O4@CSH and the successful surface loading of hydroxyl functional groups were confirmed. Phosphate adsorption kinetics, isotherm, and thermodynamic experiments showed that adsorption reaches equilibrium at 24 h, with a maximum adsorption capacity of 55.84 mg P/g under optimized experimental conditions. Adsorption kinetics fitted well to the pseudo second-order model, and equilibrium data fit the Freundlich isotherm model. Thermodynamic analysis provided a positive value for ΔH° (129.84 KJ/mol) and confirmed that phosphate adsorption on these materials is endothermic. The P-laden Fe3O4@CSH materials could be rapidly separated from aqueous solution by a magnetic separation technique within 1 min. A removal rate of more than 60% was still obtained after eight adsorption/desorption cycles, demonstrating the excellent reusability of the particles. The results demonstrated that the Fe3O4@CSH materials had high P-adsorption efficiency and were reusable.

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Kinetic analysis of sucrose activated carbon for nutrient removal in water

H2Open Journal ◽

10.2166/h2oj.2020.012 ◽

2020 ◽

Vol 3 (1) ◽

pp. 208-220

Author(s):

Sara Jamaliniya ◽

O. D. Basu ◽

Saumya Suresh ◽

Eustina Musvoto ◽

Alexis Mackintosh

Keyword(s):

Activated Carbon ◽

Kinetic Analysis ◽

Adsorption Capacity ◽

Nitrate Removal ◽

Freundlich Isotherm ◽

Langmuir Model ◽

Phosphate Removal ◽

Phosphate Adsorption ◽

Isotherm Models ◽

Nitrate Adsorption

Abstract A renewable, green activated carbon made from sucrose (sugar) was compared with traditional bituminous coal-based granular activated carbon (GAC). Single and multi-component competitive adsorption of nitrate and phosphate from water was investigated. Langmuir and Freundlich isotherm models were fitted to data obtained from the nitrate and phosphate adsorption experiments. Nitrate adsorption fits closely to either Freundlich or Langmuir model for sucrose activated carbon (SAC) and GAC with a Langmuir adsorption capacity of 7.98 and 6.38 mg/g, respectively. However, phosphate adsorption on SAC and GAC demonstrated a selective fit with the Langmuir model with an adsorption capacity of 1.71 and 2.07 mg/g, respectively. Kinetic analysis demonstrated that adsorption of nitrate and phosphate follow pseudo-second-order kinetics with rate constant values of 0.061 and 0.063 g/(mg h), respectively. Competitive studies between nitrate and phosphate were demonstrated in preferential nitrate removal with GAC and preferential phosphate removal with SAC. Furthermore, nitrate and phosphate removals decreased from 75% removal to 35% removal when subject to multi-component solutions, which highlights the need for adsorption analysis in complex systems. Overall, SAC proved to be competitive with GAC in the removal of inorganic contaminants and may represent a green alternative to coal-based activated carbon.

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

Water ◽

10.3390/w13192709 ◽

2021 ◽

Vol 13 (19) ◽

pp. 2709

Author(s):

Naoufal Bellahsen ◽

Balázs Kakuk ◽

Sándor Beszédes ◽

Zoltán Bagi ◽

Nóra Halyag ◽

...

Keyword(s):

Linear Method ◽

Phosphate Removal ◽

Iron Chloride ◽

Infrared Analysis ◽

Batch Adsorption ◽

Adsorption Method ◽

Pomegranate Peel ◽

Potential Measurement ◽

Effective Removal ◽

Full Factorial

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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Enhanced Formaldehyde Removal from Air Using Fully Biodegradable Chitosan Grafted β-Cyclodextrin Adsorbent with Weak Chemical Interaction

Polymers ◽

10.3390/polym11020276 ◽

2019 ◽

Vol 11 (2) ◽

pp. 276 ◽

Cited By ~ 11

Author(s):

Zujin Yang ◽

Hongchen Miao ◽

Zebao Rui ◽

Hongbing Ji

Keyword(s):

Chemical Interaction ◽

Synergistic Effects ◽

Freundlich Isotherm ◽

Breakthrough Curves ◽

Air Pollutant ◽

Adsorptive Capacity ◽

Crosslinking Reaction ◽

Adsorption Parameters ◽

Adsorption Performance ◽

Gaseous Formaldehyde

Formaldehyde (HCHO) is an important indoor air pollutant. Herein, a fully biodegradable adsorbent was synthesized by the crosslinking reaction of β-cyclodextrin (β-CD) and chitosan via glutaraldehyde (CGC). The as-prepared CGC showed large adsorption capacities for gaseous formaldehyde. To clarify the adsorption performance of the as-synthesized HCHO adsorbents, changing the adsorption parameters performed various continuous flow adsorption tests. It was found that the adsorption data agreed best with the Freundlich isotherm, and the HCHO adsorption kinetic data fitted well with the pseudo second order model. The breakthrough curves indicated that the HCHO adsorbing capacity of CGC was up to 15.5 mg/g, with the inlet HCHO concentration of 46.1 mg/m3, GHSV of 28 mL/min, and temperature of 20 °C. The regeneration and reusability of the adsorbent were evaluated and CGC was found to retain its adsorptive capacity after four cycles. The introduction of β-CD was a key factor for the satisfied HCHO adsorption performance of CGC. A plausible HCHO adsorption mechanism by CGC with the consideration of the synergistic effects of Schiff base reaction and the hydrogen bonding interaction was proposed based on in situ DRIFTS studies. The present study suggests that CGC is a promising adsorbent for the indoor formaldehyde treatment.

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Synthesis of nanoZrO2 via simple new green routes and its effective application as adsorbent in phosphate remediation of water with or without immobilization in Al-alginate beads

Water Science & Technology ◽

10.2166/wst.2020.318 ◽

2020 ◽

Vol 81 (12) ◽

pp. 2617-2633

Author(s):

Wondwosen Kebede Biftu ◽

Kunta Ravindhranath

Keyword(s):

Alginate Beads ◽

Phosphate Removal ◽

Nano Particles ◽

Phosphate Adsorption ◽

Isotherm Models ◽

Equilibration Time ◽

X Ray ◽

Homogeneous Method ◽

Pseudo Second Order ◽

Average Size

Abstract Nano particles of ZrO2 of average size 10.91 nm are successfully synthesized via green routes from a solvent blend of water and ethylene glycol (4:1 v/v). Bio-extract of seeds of Sapindus plant is employed as stabilizing and/or capping agent and homogeneous method of precipitation is adopted to generate the precipitating agent. The nZrO2 particles are immobilized in aluminum alginate beads (nZrO2-Al- alig). Nano-ZrO2 and beads are investigated as adsorbents for the extraction of phosphate from water. The controlling physicochemical parameters are studied for the maximum phosphate removal using simulate water. The optimum conditions are: pH: 7; sorbent dosage: 0.1 g/100 mL for nZrO2 and 0.08 g/100 mL for beads; equilibration time: 30 min.for nZrO2 and 35 min for beads; initial phosphate concentration: 50 mg/L; temperature: 30 ± 1 °C; 300 rpm. The adsorption capacities are: 126.2 mg/g for nZrO2 and 173.0 mg/g for ‘nZrO2-Al- alig’ and they are higher than many reported in literature. The beads, besides facilitating the easy filtration, are exhibiting enhanced cumulative phosphate-adsorption nature of nanoZrO2 and Al-alginate. X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray (EDX) investigations are employed in characterizing the adsorbents. Of the various isotherm models analyzed to assess the nature of adsorption, Freundlich model provides the best correlation (R2 = 0.99 for nZrO2 and R2 = 0.99 for ‘nZrO2-Al-alig’), indicating the heterogeneous and multi-layered adsorption process. Thermodynamic studies reveal the endothermic and spontaneous nature of sorption. Pseudo-second-order model of kinetics describes the adsorption well. Spent adsorbents can be regenerated with marginal loss of adsorption capacity until five cycles. The sorbents are successfully applied to remove phosphate from polluted lake water samples.

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La2O3-modified MCM-41 for efficient phosphate removal synthesized using natural diatomite as precursor

Water Science & Technology ◽

10.2166/wst.2019.186 ◽

2019 ◽

Vol 79 (10) ◽

pp. 1878-1886 ◽

Cited By ~ 1

Author(s):

Xiaoning Jia ◽

Xiaojuan He ◽

Kaixuan Han ◽

Yuhong Ba ◽

Xia Zhao ◽

...

Keyword(s):

Phosphate Concentration ◽

Phosphate Removal ◽

Treated Wastewater ◽

Molar Ratio ◽

Phosphate Adsorption ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Isothermal Model ◽

Enhanced Adsorption ◽

Ph Range

Abstract In this study, an ordered mesoporous silica modified with lanthanum oxide was synthesized using diatomite as silica source and applied for adsorption of phosphate from aqueous solution. By taking cost-effectiveness for practical application into consideration, the adsorbent with a theoretical La/SiO2 molar ratio of 0.2 (La0.2M41) possessed a promising performance. In the batch adsorption tests, the adsorbents with La2O3 loading possessed markedly enhanced adsorption capacities. Phosphate uptake by La0.2M41 was pH-dependent with the highest sorption capacities observed over a pH range of 3.0–6.0. Coexistent anions displayed an adverse effect on phosphate adsorption following the order of CO32−  > F−  > NO3− > Cl− > SO42−. In the kinetic study, phosphate adsorption onto La0.2M41 followed the pseudo-second-order equation better than the pseudo-first-order, suggesting chemisorption. The Langmuir isothermal model well described the adsorption isotherm data, showing a maximum adsorption capacity for phosphate of up to 263.16 mg/g at 298 K. In a real treated wastewater effluent with phosphate concentration of 2.5 mg P/L, La0.2M41 efficiently reduced the phosphate concentration to 28 µg P/L.

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Adsorption of phosphate ions from aqueous solutions by a CeO2 functionalized Fe3O4@SiO2 core-shell magnetic nanomaterial

Water Science & Technology ◽

10.2166/wst.2017.412 ◽

2017 ◽

Vol 76 (11) ◽

pp. 2867-2875 ◽

Cited By ~ 13

Author(s):

Jingliang Liu ◽

Jingjing Cao ◽

Yaojuan Hu ◽

Yuxiang Han ◽

Juan Zhou

Keyword(s):

Photoelectron Spectroscopy ◽

Bet Surface Area ◽

Phosphate Adsorption ◽

Batch Adsorption ◽

Core Shell ◽

X Ray ◽

Transmission Electron ◽

Adsorption Affinity ◽

Magnetic Nanomaterial ◽

Adsorption Desorption

Abstract Phosphate is generally considered to be one of the nutrients for plants which may cause eutrophication of the aquatic environment. In this study, a CeO2-functionalized Fe3O4@SiO2 core-shell magnetic nanomaterial (denoted as Fe3O4@SiO2-CeO2) was prepared and used as the adsorbent to remove phosphate from water. The adsorbents were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and N2 adsorption/desorption isotherms. Characterization results show that the particle size is around 8.63 nm, Brunauer–Emmett–Teller (BET) surface area is 179.7 m2 · g−1 and the pore volume is 0.39 cm3 · g−1 for magnetite Fe3O4@SiO2-CeO2. The adsorbents could be rapidly separated under an external magnetic field. Batch adsorption tests show that the Fe3O4@SiO2-CeO2 adsorbent exhibited high adsorption affinity for phosphate. Additionally, phosphate adsorption isotherms over the adsorbents could be well described by the Langmuir model, suggesting monolayer adsorption, and phosphate adsorption kinetics followed the pseudo-second-order kinetics. Moreover, increasing pH led to suppressed phosphate adsorption, and phosphate adsorption slightly increased with ionic strength.

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Magnetite Functionalized Nigella Sativa Seeds for the Uptake of Chromium(VI) and Lead(II) Ions from Synthetic Wastewater

Adsorption Science & Technology ◽

10.1155/2021/6655227 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Patience Mapule Thabede ◽

Ntaote David Shooto ◽

Thokozani Xaba ◽

Eliazer Bobby Naidoo

Keyword(s):

Nigella Sativa ◽

Freundlich Isotherm ◽

Synthetic Wastewater ◽

Batch Adsorption ◽

Initial Concentration ◽

X Ray ◽

Operational Conditions ◽

First Order ◽

Chromium Vi ◽

Ketonic Group

The aim of the present study was to utilise pristine and magnetite-sucrose functionalized Nigella Sativa seeds as the adsorbents for the uptake of chromium(VI) and lead(II) ions from synthetic wastewater. Prestine Nigella Sativa seeds were labelled (PNS) and magnetite-sucrose functionalized Nigella Sativa seeds (FNS). The PNS and FNS composites were characterized by Fourier-transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). The FTIR analysis of both adsorbents revealed the presence of vibrations assigned to 1749 and 1739 cm-1 (-C=O) for ketonic group for both adsorbents. The amide (-NH) peak was observed at 1533 and 1527 cm-1 on FNS and PNS composites, respectively, whilst the carboxyl group (-COOH) were observed at 1408 cm-1 on both adsorbents. The XRD results of FNS and PNS composites showed a combination of spinel structure and y -Fe2O3 phase confirming the formation of iron oxide. The influence of operational conditions such as initial concentration, temperature, pH, and contact time was determined in batch adsorption system. The kinetic data of Cr(VI) and Pb(II) ions on both adsorbents was described by pseudo-first-order (PFO) model which suggested physisorption process. The sorption rate of Cr(VI) ions was quicker, it attained equilibrium in 20 min, and the rate of Pb(II) ions was slow in 90 min. Freundlich isotherm described the mechanism of Pb(II) ions adsorption on PNS and FNS composites. Langmuir best fitted the uptake of Cr(VI) ions on PNS and FNS. The results for both adsorbents showed that the removal uptake of Pb(II) ions increased when the initial concentration was increased; however, Cr(VI) uptake decreased when the initial concentration increased. The adsorption of Cr(VI) and Pb(II) ions on both adsorbents increased with temperature.

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Adsorption of chromium (VI) ion using zeolite NaA/Fe3O4 composite derived from rice husk ash

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/947/1/012012 ◽

2021 ◽

Vol 947 (1) ◽

pp. 012012

Author(s):

Ngo Truong Ngoc Mai ◽

Nguyen Thi Anh Thu ◽

Ngo Truong Bao Trang ◽

Pham Quoc Phu ◽

Doan Van Hong Thien ◽

...

Keyword(s):

Rice Husk ◽

Rice Husk Ash ◽

Batch Adsorption ◽

Order Kinetic ◽

X Ray Diffraction ◽

Adsorption Parameters ◽

X Ray ◽

Chromium Vi ◽

Zeolite Naa ◽

Order Kinetic Model

Abstract In this study, zeolite NaA was fabricated from rice husk ash before combining with Fe3O4 to form a magnetic NaA/Fe3O4 composite. NaA/Fe3O4 composite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and Brunauer Emmett Teller (BET). The surface area and the pore size of zeolite NaA/Fe3O4 was 24.11 m2.g−1 and 23.04 Å. In addition, batch adsorption studies were carried out for the removal of chromium (VI) ion in aqueous solution. The effects of adsorption parameters, including pH solution, initial concentration of Cr (VI) ions, mass of adsorbent, and contact time were investigated. The maximum equilibrium adsorption capacity of zeolite NaA and NaA/Fe3O4 was 22.554 mg.g−1 and 13.722 mg.g−1, respectively. The pseudo-first order kinetic model fitted well to the experimental data. The regeneration of the adsorbent was also investigated for three cycles.

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