Next Article in Journal
Path Analysis of the Main Control Factors of Transpiration in Greenhouse, Drip-Irrigated Grapes in Cold Areas of Northeast China
Next Article in Special Issue
Disinfection of Outdoor Livestock Water Troughs: Effect of TiO2-Based Coatings and UV-A LED
Previous Article in Journal
Organic Matter and Heavy Metal Ions Removal from Surface Water in Processes of Oxidation with Ozone, UV Irradiation, Coagulation and Adsorption
Previous Article in Special Issue
Photodegradation Behavior of Agricultural Antibiotic Oxytetracycline in Water
 
 
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Removal of Phosphorus by Ferric Ion-Rich Solutions Prepared Using Various Fe(III)-Containing Minerals

Department of Civil and Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
*
Author to whom correspondence should be addressed.
Water 2022, 14(22), 3765; https://doi.org/10.3390/w14223765
Received: 25 October 2022 / Revised: 13 November 2022 / Accepted: 17 November 2022 / Published: 19 November 2022
(This article belongs to the Special Issue Agricultural Environment and Water Technology)

Abstract

:
Various biological, chemical, and physical technologies have been studied to effectively remove total phosphorus (T-P) from wastewater. Among them, some mineral suspensions and cations in the aqueous phase have shown great potential for promoting phosphorus removal via chemical precipitation. Herein, we investigated the efficiency of T-P removal using various chemical-based cations (Fe2+, Fe3+, Mg2+, and Al3+); ferric ions (Fe3+) showed the highest T-P-removal efficiency (33.1%), regardless of the type of anion (Cl, NO3, and SO42−). To prepare natural Fe3+-rich solutions, three different Fe(III)-rich minerals (hematite, lepidocrocite, and magnetite) were treated with various HCl concentrations to maximize the dissolved Fe3+ amounts. Lepidocrocite in 2 N HCl showed the most effective Fe3+-leaching ability (L-Fe dissolved solution). Almost no significant difference in Fe3+ leaching was observed between HCl and H2SO4, whereas lepidocrocite-2 N H2SO4 showed the highest T-P-removal ability (91.5%), with the formation of amorphous Fe(III)-P precipitates. The L-Fe dissolved solution exhibited a higher T-P-removal efficiency than polyammonium chloride under real wastewater conditions. Our results can provide fundamental knowledge about the effect of cations on T-P removal in wastewater treatment and the feasibility of using the Fe3+ leaching solution prepared from Fe(III)-containing minerals for efficient T-P removal via chemical precipitation.

1. Introduction

The total amount of phosphorus (T-P) in inorganic and organic phosphorus compounds in water is an essential element usually generated from various anthropogenic sources such as detergents, fertilizers, animal feedlots, meat, and livestock wastewater [1,2,3,4]. Economic development and population growth driven by rapid industrialization have increased the demand for phosphorus as an agricultural fertilizer to stimulate the growth of plants and chemical manufacturing processes [5,6]. However, it is a substance that causes serious environmental problems [7]. When wastewater containing a large amount of phosphorus is discharged into rivers, lakes, or the sea, it greatly affects the surrounding ecosystem owing to the excessive accumulation of nutrients in water bodies [8]. Eutrophication and algal blooms may occur by accelerating the growth of algae and organisms, endangering the existence of aquatic plants and animals due to the lack of oxygen. Therefore, regulations to reduce phosphorus emissions have increased worldwide, resulting in reinforced emission limits for wastewater treatment facilities [9].
In general, three methods for phosphorus removal are typically used worldwide: biological (biomass growth, bacterial polyphosphate accumulation), physical (settling, filtration), and chemical (precipitation) treatments [10,11,12,13,14,15,16]. Each wastewater treatment method has its own advantages and disadvantages. The biological process is simple, inexpensive, and well-accepted by the public [17]. However, they usually require large areas, generate large amounts of sludge, and are slow and inconsistent in maintaining low phosphorus concentrations [17,18]. Although physical methods, such as membranes with reverse osmosis, are known to be able to remove almost all of the contaminants in wastewater, these systems require high pressure, which in turn requires a reliable and demanding energy source [19]. In contrast, chemical-based phosphorus removal is associated with high sludge production and disposal challenges but is extremely durable, technologically simple, and economically advantageous [8]. Physicochemical treatment using metal ions is a representative removal technique, and some studies have shown the potential use of metal-containing minerals (Ca, Fe, Mg, and Al) [16,20,21]. However, the direct application of metal-containing minerals has some drawbacks, such as the massive production of unreacted mineral sludge and waste [22]. Therefore, a novel approach should be developed to overcome the disadvantages of the direct use of metal-containing minerals and achieve effective phosphorus precipitation in wastewater treatment plants (WWTP).
In the present study, we first investigated T-P removal by various chemical-based cations (Fe2+, Fe3+, Mg2+, and Al3+) to determine the most efficient cation for the chemical precipitation of T-P. Further, the effect of the number of anions on T-P removal was evaluated using various Fe3+ solutions prepared using different Fe(III) chemicals. To prepare natural Fe3+-dissolved solutions, three different Fe(III)-containing minerals—hematite (α-Fe2O3), lepidocrocite (γ-FeOOH), and magnetite (Fe3O4)—were used for Fe(III) extraction at different HCl concentrations and applied for T-P removal (Scheme 1). Finally, various parametric studies and surface analyses, such as X-ray diffraction (XRD), scanning electron microscope-energy dispersive spectrometry (SEM-EDS), and Fourier-transform infrared spectroscopy (FTIR), were conducted to investigate the T-P precipitation mechanism.

2. Materials and Methods

2.1. Chemicals and Minerals

Sodium hydrogen phosphate (Na2HPO4 · 12H2O; 98.0%; Samchun Pure Chemical Co., LTD., Seoul, Korea), hydrochloric acid (HCl; 35%; Daejung Chemical & Metal Co., LTD., Seoul, Korea), Iron(II) chloride (FeCl2 · 4H2O; 98%; Sigma Aldrich, Saint Louis, MO, USA), Iron(III) chloride (FeCl3 · 6H2O; 97%; Sigma Aldrich, USA), iron(III) nitrate (Fe(NO3)3 · 9H2O; ≥98%; Sigma Aldrich, USA), iron(II) sulfate (FeSO4 · 7H2O; ≥99%; Sigma Aldrich, USA), magnesium chloride (MgCl2; Sigma Aldrich, USA), aluminum chloride (AlCl3·6H2O; >99%; Sigma Aldrich, USA), and sodium phosphate (Na2HPO4 · 2H2O; Sigma Aldrich, USA) were used to conduct the experiments. Hematite (α-Fe2O3), lepidocrocite (γ-FeOOH), and magnetite (Fe3O4) were obtained from the Bayferrox LANXESS Corp. In this study, deionized water (DIW; 18.3 MΩ) obtained from an ultrapure filtration system (HUMAN POWER I+ water purification system) was used to prepare all solutions.

2.2. T-P Removal via Chemical Induction Using Cation Solutions

A batch experiment was performed using a glass beaker to characterize the removal of T-P via chemical induction using cation solutions. The PO43−-P solution (100 mg·L−1) was prepared in a 200 mL beaker. T-P-removal experiments were initiated by adding cation solutions (Fe2+, Fe3+, Mg2+, and Al3+, 10 mL, 1 mM) and different Fe2+ (FeCl2 and FeSO4) and Fe3+ anions (FeCl3 and Fe(NO3)3).

2.3. T-P Removal by Solutions Containing Dissolved Fe3+ That Were Prepared Using Fe(III)-Containing Minerals

To determine the appropriate concentration of Fe minerals and strong acids, a batch experiment was conducted with 10 g·L−1 of Fe(III)-containing minerals, and the kinetics of Fe dissolution were monitored. Other experiments were conducted with Fe(III)-containing minerals (20 g·L−1) to confirm the amount of Fe dissolution after mixing for 24 h at different HCl concentrations.
Batch kinetic experiments were conducted to investigate the maximum amount of Fe dissolution with different contents of lepidocrocite (20–200 g·L−1) in 2 N HCl, and 40 g·L−1 was selected as the optimal mineral content to investigate the T-P removal by lepidocrocite-Fe(III) dissolved solution (L-Fe dissolved solution) prepared with different strong acids (HCl and H2SO4) and concentrations (1, 2, and 4 N). An identical amount of Fe3+ (3 mg·L−1) was transferred to a beaker containing 10 mg·L−1 of PO43−-P for the T-P-removal experiments.
For practical application, the T-P-removal efficiencies of different amounts of initial Fe3+ (1, 2, and 5 mg·L−1) in L-Fe dissolved solutions were compared with those of a commercial polyammonium chloride (PAC) (1, 2, 5 mg·L−1). An exact amount of artificial PO43−-P solution was spiked into a beaker containing approximately 1 mg·L−1 T-P of secondary treated real wastewater (Initial pH = 7.4) obtained from a WWTP in Bucheon, South Korea. The prepared initial concentration of T-P was 10 mg·L−1, as the other laboratory experiments described above.

2.4. Analytical Methods

The concentration of T-P in aqueous solution was measured using a spectrophotometer (DR 3900, HACH) after filtering the suspension through a 0.2 µm membrane filter (Whatman). The molybdovanadate method with acid persulfate digestion (method 10127) was used in this study. The Fe concentration of the suspension was measured using a UV-Vis spectrometer (GENESYS 10S, Thermo Scientific, Waltham, MA, USA). The concentration of Fe was quantified by measuring the peak of absorbance (562 nm) using the ferrozine method [23].
Changes in the functional groups on the surface of the precipitates after T-P removal were monitored using an FTIR spectrometer (NICOLET iS10, Thermo) with a Smart OMINI-Transmission Accessory. The IR spectra (4000–400 cm−1) were recorded at a resolution of 4 cm−1 by averaging 50 scans. The mixture of powders (mass ratio of KBr to sample was 50:1) was transferred to a 7-mm pellet die, and the KBr pellet was analyzed after fabrication with a pellet press.
To identify the structural characteristics of the precipitates, XRD (Rigaku Smartlab, Tokyo, Japan) was performed. The morphology and local elemental composition of the precipitates were identified by SEM-EDS analysis using an EM-30AXN instrument (Coxem, Daejeon, Korea).

3. Results and Discussion

3.1. Removal of T-P via Chemical Induction Using Cation Solutions

Figure 1a shows the amount of T-P (100 mg·L−1) removed by different cation solutions. A comparative experiment was performed to identify the most effective cation for T-P removal. The Fe3+ solution showed the highest removal efficiency (33.1%), followed by Mg2+ (7.3%), Fe2+ (6.2%), and Al3+ (4.1%), indicating the great potential of the Fe3+ solution for T-P removal. The difference in the T-P-removal effects could be explained by the different moles of Fe2+ and Fe3+ required for T-P removal (Equations (1) and (2)). The general mechanism of the reaction of Fe2+ and Fe3+ with PO43− follows the following chemical equations:
3 Fe 2 + + 2 PO 4 3     Fe 3 ( PO 4 ) 2
Fe 3 + + PO 4 3     FePO 4
The anion effect of the Fe2+ and Fe3+ solutions was further investigated to identify the potential loss of T-P by the anion during the reaction (Figure 1b). FeCl2 and FeSO4 (both Fe2+ chemicals) showed only 6.8% and 9.5% T-P removal, whereas almost 37.4% and 34.4% T-P removal was obtained by FeCl3 and Fe(NO3)3 (both Fe3+ chemicals), respectively. As a result, we concluded that the effect of the Fe charge amount was greater than that of the counter anion in the T-P removal by Fe-dissolved solutions when various anions were used.

3.2. Monitoring Fe(III) Dissolution

To investigate the Fe dissolution of Fe-containing minerals (10 g·L−1) in 2 N HCl, we monitored the concentrations of Fe(II), Fe(III), and total Fe during the 1-h reaction (Figure 2a–c). The dissolved Fe concentrations in lepidocrocite and magnetite suspensions increased continuously and reached an equilibrium state, except in the case of hematite, which showed an almost negligible amount of Fe dissolution owing to its high strength and crystallinity compared to the other minerals [24]. In the case of magnetite, total Fe concentrations of 5472.5 mg·L−1 and 5919.9 mg·L−1 were observed at 24 and 51 h, respectively. In addition, 3699.3 and 4490.8 mg·L−1 of dissolved Fe3+ were obtained at each time because magnetite has a mixed Fe oxidation state (Fe(II):Fe(III) = 1:2). On the other hand, lepidocrocite showed a similar amount of total Fe (6050.1 mg·L−1 at 51 h) to that of magnetite, but a higher Fe3+ amount (5538.4 mg·L−1 at 51 h) than that of magnetite. Although lepidocrocite is an Fe(III) oxyhydroxide, we observed a small amount of dissolved Fe2+ in 2 N HCl, probably due to the presence of some Fe(II) impurities during mineral synthesis.
Figure 2d,e show a comparison of Fe dissolution at different HCl concentrations (2−8 N) for lepidocrocite and magnetite (20 g·L−1). For lepidocrocite, we observed a slight increase in Fe dissolution (both total Fe and Fe3+ ions) with different HCl concentrations because lepidocrocite tends to be easily dissolved in a wide range of acidic solutions. For magnetite, a significant increase in Fe dissolution was observed as the HCl concentration increased. Interestingly, the gap between the total Fe and Fe3+ in the magnetite-HCl suspension grew continuously closer because the dissolved Fe2+ can be oxidized to Fe3+ in a strong acid [25]. As a result, the amount of Fe3+ dissolved in 2 N HCl was 10,213.6 mg·L−1 for lepidocrocite, which was similar to that of magnetite in 6 M (10,295.5 mg·L−1). Because there was no significant difference in the amount of Fe dissolution after 24 h in the experiments, subsequent experiments were conducted with a solution obtained by dissolving lepidocrocite (L-Fe dissolved solution) for 24 h.

3.3. Removal of T-P by L-Fe Dissolved Solution

Figure 3a shows the equilibrium amount of Fe3+ dissolved in the lepidocrocite suspension at different initial contents. In the case of a small amount of lepidocrocite (<40 g·L−1), the dissolved Fe3+ amount rapidly increased as the lepidocrocite content increased but reached the maximum concentration after almost 100 g·L−1. Thus, the initial lepidocrocite concentration was fixed at 40 g·L−1 for further studies. We also conducted additional experiments to investigate the amount of Fe dissolved at various normal concentrations of HCl and H2SO4 (Figure 3b,c). The dissolved amount of Fe continued to increase as the acid concentration increased to 2 N. Specifically, the total dissolved Fe in 2 N HCl was 24,951.7 mg·L−1, which was slightly higher than that of 2 N H2SO4 (23,089.7 mg·L−1). With regard to Fe3+, 2 N HCl and 2 N H2SO4 showed dissolved Fe contents of 22,988.5 mg·L−1 and 21,018.4 mg·L−1 with a negligible amount of Fe2+ (1963.2 mg·L−1 and 1071.3 mg·L−1), respectively. These results indicate that higher amounts of total Fe and Fe3+ were obtained using the suspension prepared using HCl at a normal concentration of 2 N.
To determine the removal capacity of the L-Fe dissolved solution prepared in different acids, batch experiments were performed using the same amount of Fe3+ dissolved solutions prepared at different acid concentrations. All the L-Fe dissolved solutions prepared at different HCl concentrations showed almost identical removal efficiencies (1 N = 37.6%, 2 N = 37.0%, and 4 N = 37.2%) (Figure 4a). We also observed that pH was not significantly reduced in 1 and 2 N HCl-prepared solutions due to the injection of a small volume of Fe dissolved stock solution, while 4 N showed a slight decrease in pH from 7.2 to 6.53. The results also indicated that pH variation may not have significantly influenced T-P removal in this study. Figure 4b shows the cases of T-P removal by H2SO4-prepared solutions. L-Fe dissolved in 2 N H2SO4 showed the highest removal efficiency (51.8%), followed by solutions dissolved in 4 N (40.9%) and 1 N (33.8%). Similar to the HCl experiments, almost no change in the pH was observed in any of the H2SO4 experiments. The results confirmed that the L-Fe dissolved solution prepared with 2 N H2SO4 was the most effective for the removal of T-P. This might be because anions compete with phosphate for adsorption and inhibit the adsorption of phosphorus by ferric iron ions [26]. Although the anion inhibition effects of SO42− and Cl were not significantly different, we suspected that the inhibition effect of anions could be reduced owing to the half molarity of anions in the H2SO4 solution compared to that of the HCl solution.
Figure 4c shows the pH effect on T-P removal, showing that alkaline pHs higher than 9 can remove T-P via OH-precipitation. However, there was no significant T-P removal and pH variation at initial pH 7, indicating the neglect removal of T-P by OH-precipitation and pH effect in this study, respectively. To further validate the practical application in the WWTP, we obtained real wastewater (secondary treated wastewater) and used it to compare the removal efficiency of T-P between the L-Fe dissolved solution and PAC (Figure 5). In general, the T-P-removal efficiency continuously increased as the metal ion content increased. The T-P-removal efficacy and metal ion contents were highly correlated for both cases, with R2 values of 0.99 and 0.97, respectively. Interestingly, the L-Fe dissolved solution showed a slope of 18.7 (Figure 5a), whereas PAC showed a slope of 12.1 (Figure 5b), indicating that the L-Fe dissolved solution had a higher efficiency for T-P removal in practical applications.
The matrix effect in wastewater on T-P removal may be negligible because no significant difference in T-P removal was observed between the experimental data obtained from real wastewater and DI water. For comparison with other studies, the most frequently used ferric-type coagulant, i.e., ferric chloride, was compared at the same ratio of Fe:P (0.9). Almost complete T-P removal (100%) was observed in this study, whereas other ferric chloride-based experiments showed lower removal efficiency (~80%) [27,28], indicating the applicability of the L-Fe dissolved solution.

3.4. Analysis of the Precipitates

Figure 6 shows the FTIR spectra of pure lepidocrocite and P-Fe precipitates using the L-Fe solution prepared with different acids. The broad absorption near 3100 cm−1 was assigned to the typical O–H stretching vibration band of oxyhydroxides of pure lepidocrocite (Figure 6a) [29]. The bands around 1160, 1020, and 750 cm−1 that appeared in the pure lepidocrocite sample are attributed to their characteristic vibrations [30,31]. The absorption band near 1650 cm−1 is ascribed to the vibrations of the H-O-H group, indicating the presence of physisorbed water on the surface due to weathering over time, whereas the broad band around 3410 cm−1 is assigned to the OH group, which is associated with Fe [32,33]. The asymmetric stretching vibration of the PO43− group was detected at approximately 1060 cm−1 in Figure 6b,c, which is caused by the chemical bond between the T-P and L-Fe dissolved solutions [34]. No significant differences were observed in the FTIR results of the HCl and H2SO4 prepared samples, except that the HCl sample revealed a peak at 669 cm−1, indicating low absorption of C-Cl (Figure 6b) [35].
To investigate the physical characteristics of the precipitates after T-P removal using the L-Fe dissolved solution with H2SO4, additional XRD and SEM-EDS analyses were performed (Figure 7). Compared to pure lepidocrocite, which showed an almost homogenous particle size and the absence of P (Figure 7a), the precipitate obtained after using the L-Fe dissolved solution with H2SO4 (Figure 7b) showed the formation of different-sized particles and a significant decrease in Fe content with an increase in phosphorus and sulfur contents. The initial Fe content of lepidocrocite (55.8%) decreased to 24.6%, and the contents of P and S increased from 0% to 11.7% and 2.8%, respectively, after T-P removal (Table 1). This result confirms the formation of Fe(III)-P precipitates and the rest of the ferric sulfate solution used in the present study. An additional XRD analysis was conducted to investigate the mineral phase of the precipitate (Figure 7c), but no clear crystalline peaks were observed, indicating the formation of amorphous Fe(III)–P precipitates, such as FePO4 [36].

4. Conclusions

In this study, Fe3+ showed the highest T-P-removal efficiency compared to Fe2+, Mg2+, and Al3+, and the number of anions did not show a significant effect when Fe2+ and Fe3+ solutions were used for T-P removal. Among the three different Fe(III)-containing minerals, lepidocrocite dissolved in 2 N H2SO4 for 24 h showed the highest T-P-removal efficiency, owing to its relatively soft crystalline characteristics, resulting in high Fe3+ dissolution in a strong acid. Interestingly, the T-P-removal efficiency under real wastewater conditions revealed that the L-Fe solution surpassed the efficiency of PAC at the same Fe3+ and Al3+ content. Because we did not observe any significant pH drop after applying the L-Fe dissolved solution and obtained a high T-P-removal efficiency without additional unreacted chemical/mineral sludge, the results highlight the potential use of mineral-dissolved Fe3+ solution for effective T-P removal in WWTP via cost-effective and eco-friendly methods without additional sludge production.

Author Contributions

Writing—Original draft preparation, investigation, data curation, J.J.; investigation, data curation, M.C.; investigation, writing, A.K.R.P.; investigation, visualization, J.L.; supervision, project administration, funding acquisition, writing—review and editing, S.B. All authors have read and agreed to the published version of the manuscript.

Funding

This work was partially supported by the Korea Environment Industry & Technology Institute (KEITI) through a project for developing innovative drinking water and wastewater technologies funded by the Korea Ministry of Environment (MOE) (RE202201776), the Korea Ministry of Environment as Waste to Energy-Recycling Human Resource Development Project (YL-WE-21-001), and Konkuk University’s research support program for its faculty on sabbatical leave in 2021.

Data Availability Statement

The data presented in the study is available on request from the corresponding author.

Acknowledgments

Thank you to all participants for their strong support.

Conflicts of Interest

The author declares that she has no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

References

  1. Kroiss, H.; Rechberger, H.; Egle, L. Phosphorus in water quality and waste management. Integr. Waste Manag. 2011, 2, 18482. [Google Scholar] [CrossRef]
  2. Holtan, H.; Kamp-Nielsen, L.; Stuanes, A.O. Phosphorus in soil, water and sediment: An overview. Phosphorus Freshw. Ecosyst. 1988, 34, 19–34. [Google Scholar] [CrossRef]
  3. Bouwman, L.; Goldewijk, K.K.; Van Der Hoek, K.W.; Beusen, A.H.W.; van Vuuren, D.P.; Willems, J.; Rufino, M.C.; Stehfest, E. Exploring global changes in nitrogen and phosphorus cycles in agriculture induced by livestock production over the 1900–2050 period. Proc. Natl. Acad. Sci. USA 2013, 110, 20882–20887. [Google Scholar] [CrossRef]
  4. Jarvie, H.P.; Neal, C.; Withers, P.J. Sewage-effluent phosphorus: A greater risk to river eutrophication than agricultural phosphorus? Sci. Total Environ. 2006, 360, 246–253. [Google Scholar] [CrossRef] [PubMed]
  5. Shin, J.; Kwak, J.; Kim, S.; Son, C.; Lee, Y.-G.; Kim, J.; Bae, S.; Park, Y.; Lee, S.-H.; Chon, K. Highly selective recovery of phosphate ions using a novel carbonaceous adsorbent synthesized via co-pyrolysis of spent coffee grounds and steel slags: A potential phosphatic fertilizer. Chem. Eng. J. 2023, 451, 138978. [Google Scholar] [CrossRef]
  6. Wang, H.; Xiao, K.; Yang, J.; Yu, Z.; Yu, W.; Xu, Q.; Wu, Q.; Liang, S.; Hu, J.; Hou, H.; et al. Phosphorus recovery from the liquid phase of anaerobic digestate using biochar derived from iron-rich sludge: A potential phosphorus fertilizer. Water Res. 2020, 174, 115629. [Google Scholar] [CrossRef]
  7. Correll, D.L. The role of phosphorus in the eutrophication of receiving waters: A review. J. Environ. Qual. 1998, 27, 261–266. [Google Scholar] [CrossRef]
  8. Mkilima, T.; Bazarbayeva, T.; Assel, K.; Nurmukhanbetova, N.N.; Ostretsova, I.B.; Khamitova, A.S.; Makhanova, S.; Sergazina, S. Pore size in the removal of phosphorus and nitrogen from poultry slaughterhouse wastewater using polymeric nanofiltration membranes. Water 2022, 14, 2929. [Google Scholar] [CrossRef]
  9. Bashar, R.; Gungor, K.; Karthikeyan, K.; Barak, P. Cost effectiveness of phosphorus removal processes in municipal wastewater treatment. Chemosphere 2018, 197, 280–290. [Google Scholar] [CrossRef]
  10. Peng, Y.; He, S.; Wu, F. Biochemical processes mediated by iron-based materials in water treatement: Enhancing nitrogen and phosphorus removal in low C/N ratio wastewater. Sci. Total Environ. 2021, 775, 145137. [Google Scholar] [CrossRef]
  11. Jia, Y.; Zeng, W.; Fan, Z.; Meng, Q.; Liu, H.; Peng, Y. An effective titanium salt dosing strategy for phosphorus removal from wastewater: Synergistic enhancement of chemical and biological treatment. Sci. Total Environ. 2022, 842, 156960. [Google Scholar] [CrossRef]
  12. Nguyen, T.A.H.; Ngo, H.H.; Guo, W.S.; Nguyen, T.T.; Vu, N.D.; Soda, S.; Nguyen, T.H.H.; Nguyen, M.K.; Tran, T.V.H.; Dang, T.T.; et al. White hard clam (Meretrix lyrata) shells as novel filter media to augment the phosphorus removal from wastewater. Sci. Total Environ. 2020, 741, 140483. [Google Scholar] [CrossRef]
  13. Wang, H.; Dai, J.; Chen, H.; Wang, F.; Zhu, Y.; Liu, J.; Zhou, B.; Yuan, R. Adsorption of phosphate by Mg/Fe-doped wheat straw biochars optimized using response surface methodology: Mechanisms and application in domestic sewage. Environ. Eng. Res. 2022, 28, 210602. [Google Scholar] [CrossRef]
  14. Naz, A.; Masood, H.; Ehsan, S.; Tahir, T. Removal of acid black 1 by acacia concinna; adsorption kinetics, isotherm and thermodynamic study. Membr. Water Treat. 2020, 11, 407–416. [Google Scholar] [CrossRef]
  15. Nielsen, P.H.; McIlroy, S.J.; Albertsen, M.; Nierychlo, M. Re-evaluating the microbiology of the enhanced biological phosphorus removal process. Curr. Opin. Biotechnol. 2019, 57, 111–118. [Google Scholar] [CrossRef] [PubMed]
  16. Bellier, N.; Chazarenc, F.; Comeau, Y. Phosphorus removal from wastewater by mineral apatite. Water Res. 2006, 40, 2965–2971. [Google Scholar] [CrossRef] [PubMed]
  17. Crini, G.; Lichtfouse, E. Advantages and disadvantages of techniques used for wastewater treatment. Environ. Chem. Lett. 2019, 17, 145–155. [Google Scholar] [CrossRef]
  18. Pratt, C.; Parsons, S.A.; Soares, A.; Martin, B.D. Biologically and chemically mediated adsorption and precipitation of phosphorus from wastewater. Curr. Opin. Biotechnol. 2012, 23, 890–896. [Google Scholar] [CrossRef] [PubMed]
  19. Kyllönen, H.; Heikkinen, J.; Ceras, J.; Fernandez, C.; Porc, O.; Grönroos, A. Membrane-based conceptual design of reuse water production from candy factory wastewater. Water Sci. Technol. 2021, 84, 1389–1402. [Google Scholar] [CrossRef]
  20. Yin, Z.; Chen, Q.; Zhao, C.; Fu, Y.; Li, J.; Feng, Y.; Li, L. A new approach to removing and recovering phosphorus from livestock wastewater using dolomite. Chemosphere 2020, 255, 127005. [Google Scholar] [CrossRef]
  21. Li, R.; Kelly, C.; Keegan, R.; Xiao, L.; Morrison, L.; Zhan, X. Phosphorus removal from wastewater using natural pyrrhotite. Colloids Surfaces A Physicochem. Eng. Asp. 2013, 427, 13–18. [Google Scholar] [CrossRef]
  22. Paul, E.; Laval, M.L.; Sperandio, M. Excess sludge production and costs due to phosphorus removal. Environ. Technol. 2001, 22, 1363–1371. [Google Scholar] [CrossRef] [PubMed]
  23. Jung, J.; Kim, J.; Yoon, S.; Reddy, P.A.K.; Hwang, Y.; Bae, S. The role of Fe dissolution in olivine-hydroxylamine-induced Fenton reaction for enhanced oxidative degradation of organic pollutant. Chemosphere 2022, 306, 135557. [Google Scholar] [CrossRef] [PubMed]
  24. Bae, S.; Lee, W. Enhanced reductive degradation of carbon tetrachloride by biogenic vivianite and Fe(II). Geochim. Et Cosmochim. Acta 2012, 85, 170–186. [Google Scholar] [CrossRef]
  25. Yoon, S.; Bae, S. Novel synthesis of nanoscale zerovalent iron from coal fly ash and its application in oxidative degradation of methyl orange by fenton reaction. J. Hazard. Mater. 2018, 365, 751–758. [Google Scholar] [CrossRef]
  26. Wu, H.-F.; Wang, J.-P.; Duan, E.-G.; Hu, W.-H.; Dong, Y.-B.; Zhang, G.-Q. Phosphorus removal by adsorbent based on poly-aluminum chloride sludge. Water Sci. Eng. 2020, 13, 193–201. [Google Scholar] [CrossRef]
  27. Caravelli, A.H.; Contreras, E.M.; Zaritzky, N.E. Phosphorous removal in batch systems using ferric chloride in the presence of activated sludges. J. Hazard. Mater. 2010, 177, 199–208. [Google Scholar] [CrossRef] [PubMed]
  28. Zhou, Y.; Xing, X.-H.; Liu, Z.; Cui, L.; Yu, A.; Feng, Q.; Yang, H. Enhanced coagulation of ferric chloride aided by tannic acid for phosphorus removal from wastewater. Chemosphere 2008, 72, 290–298. [Google Scholar] [CrossRef]
  29. Cui, H.; Ren, W.; Lin, P.; Liu, Y. Structure control synthesis of iron oxide polymorph nanoparticles through an epoxide precipitation route. J. Exp. Nanosci. 2012, 8, 869–875. [Google Scholar] [CrossRef]
  30. Moreno, E.M.; Zayat, M.; Morales, M.P.; Serna, C.J.; Roig, A.; Levy, D. Preparation of narrow size distribution superparamagnetic γ-Fe2O3 nanoparticles in a sol-gel transparent SiO2 matrix. Langmuir 2002, 18, 4972–4978. [Google Scholar] [CrossRef]
  31. Burstein, G.T. The iron oxides: Structure, properties, reactions, occurrence and uses. Corros. Sci. 1997, 39, 1499–1500. [Google Scholar] [CrossRef]
  32. Yousefi, T.; Davarkhah, R.; Golikand, A.N.; Mashhadizadeh, M.H.; Abhari, A. Facile cathodic electrosynthesis and characterization of iron oxide nano-particles. Prog. Nat. Sci. 2013, 23, 51–54. [Google Scholar] [CrossRef]
  33. Hou, J.; Luo, J.; Song, S.; Li, Y.; Li, Q. The remarkable effect of the coexisting arsenite and arsenate species ratios on arsenic removal by manganese oxide. Chem. Eng. J. 2017, 315, 159–166. [Google Scholar] [CrossRef]
  34. Liu, Y.; Li, Z.; You, Y.; Zheng, X.; Wen, J. Synthesis of different structured FePO4 for the enhanced conversion of methyl cellulose to 5-hydroxymethylfurfural. RSC Adv. 2017, 7, 51281–51289. [Google Scholar] [CrossRef]
  35. Lee, K.E.; Teng, T.T.; Morad, N.; Poh, B.T.; Mahalingam, M. Flocculation activity of novel ferric chloride–polyacrylamide (FeCl3-PAM) hybrid polymer. Desalination 2011, 266, 108–113. [Google Scholar] [CrossRef]
  36. Liu, Y.; Zhou, Y.; Zhang, J.; Zhang, S.; Xu, S. The transformation from amorphous iron phosphate to sodium iron phosphate in sodium-ion batteries. Phys. Chem. Chem. Phys. 2015, 17, 22144–22151. [Google Scholar] [CrossRef]
Scheme 1. Experimental concept of this study.
Scheme 1. Experimental concept of this study.
Water 14 03765 sch001
Figure 1. Removal of T-P by (a) different cation solutions and (b) Fe solutions with different anions. Experimental conditions: [cations] = 1 mM, [PO43−-P]0 = 100 mg·L−1.
Figure 1. Removal of T-P by (a) different cation solutions and (b) Fe solutions with different anions. Experimental conditions: [cations] = 1 mM, [PO43−-P]0 = 100 mg·L−1.
Water 14 03765 g001
Figure 2. Kinetics of Fe dissolution in suspensions of Fe(III)-containing minerals (2 N HCl); (a) hematite, (b) magnetite, (c) lepidocrocite, (d) dissolved Fe amount for lepidocrocite, and (e) magnetite in different HCl concentrations. Experimental conditions: (ac) [minerals]0 = 10 g·L−1, (d,e) [minerals]0 = 20 g·L−1.
Figure 2. Kinetics of Fe dissolution in suspensions of Fe(III)-containing minerals (2 N HCl); (a) hematite, (b) magnetite, (c) lepidocrocite, (d) dissolved Fe amount for lepidocrocite, and (e) magnetite in different HCl concentrations. Experimental conditions: (ac) [minerals]0 = 10 g·L−1, (d,e) [minerals]0 = 20 g·L−1.
Water 14 03765 g002
Figure 3. Concentrations of Fe ions under different variables; (a) Fe3+ dissolution at different amounts of lepidocrocite (2 N HCl), (b) at different normality of HCl, and (c) H2SO4. Experimental conditions: (b,c) [minerals]0 = 40 g·L−1.
Figure 3. Concentrations of Fe ions under different variables; (a) Fe3+ dissolution at different amounts of lepidocrocite (2 N HCl), (b) at different normality of HCl, and (c) H2SO4. Experimental conditions: (b,c) [minerals]0 = 40 g·L−1.
Water 14 03765 g003
Figure 4. T-P-removal efficiency using L-Fe dissolved solution with different normality; (a) L-Fe dissolved solutions with HCl mixing, (b) L-Fe dissolved solutions with H2SO4 mixing. Experimental conditions: [PO43−-P]0 = 10 mg·L−1, [Fe3+ solution]0 = 3 mg·L−1. (c) T-P removal efficiency and variation of final pH in different pH solutions.
Figure 4. T-P-removal efficiency using L-Fe dissolved solution with different normality; (a) L-Fe dissolved solutions with HCl mixing, (b) L-Fe dissolved solutions with H2SO4 mixing. Experimental conditions: [PO43−-P]0 = 10 mg·L−1, [Fe3+ solution]0 = 3 mg·L−1. (c) T-P removal efficiency and variation of final pH in different pH solutions.
Water 14 03765 g004
Figure 5. Removal efficiency of T-P by (a) L-Fe dissolved solutions prepared in 2 N H2SO4 (b) and PAC.
Figure 5. Removal efficiency of T-P by (a) L-Fe dissolved solutions prepared in 2 N H2SO4 (b) and PAC.
Water 14 03765 g005
Figure 6. FTIR spectra from different materials; (a) pure lepidocrocite, P-Fe precipitates after using L-Fe dissolved solution with (b) HCl and (c) H2SO4.
Figure 6. FTIR spectra from different materials; (a) pure lepidocrocite, P-Fe precipitates after using L-Fe dissolved solution with (b) HCl and (c) H2SO4.
Water 14 03765 g006
Figure 7. SEM-EDS analysis of (a) pure lepidocrocite, (b) the precipitates after T-P removal by L-Fe dissolved solution with H2SO4, and (c) XRD results of precipitates after T-P removal by lepidocrocite-H2SO4 solution. EDS electron mapping for different conditions (a-1,b-1).
Figure 7. SEM-EDS analysis of (a) pure lepidocrocite, (b) the precipitates after T-P removal by L-Fe dissolved solution with H2SO4, and (c) XRD results of precipitates after T-P removal by lepidocrocite-H2SO4 solution. EDS electron mapping for different conditions (a-1,b-1).
Water 14 03765 g007
Table 1. EDS results of precipitates before and after reaction.
Table 1. EDS results of precipitates before and after reaction.
Fe (wt%)O (wt%)P (wt%)S (wt%)
Before reaction55.843.300
After reaction24.660.211.72.8
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Jung, J.; Choi, M.; Police, A.K.R.; Lee, J.; Bae, S. Removal of Phosphorus by Ferric Ion-Rich Solutions Prepared Using Various Fe(III)-Containing Minerals. Water 2022, 14, 3765. https://doi.org/10.3390/w14223765

AMA Style

Jung J, Choi M, Police AKR, Lee J, Bae S. Removal of Phosphorus by Ferric Ion-Rich Solutions Prepared Using Various Fe(III)-Containing Minerals. Water. 2022; 14(22):3765. https://doi.org/10.3390/w14223765

Chicago/Turabian Style

Jung, Jueun, Minhee Choi, Anil Kumar Reddy Police, Jungho Lee, and Sungjun Bae. 2022. "Removal of Phosphorus by Ferric Ion-Rich Solutions Prepared Using Various Fe(III)-Containing Minerals" Water 14, no. 22: 3765. https://doi.org/10.3390/w14223765

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop