A Comprehensive Review on the Progress of Coagulation for Natural Organic Matter Removal in Water Treatment

Shivraj Shivraj; Wasim Quraishi; Subhankar Basu

doi:10.36312/esaintika.v7i2.1342

Authors

Shivraj Shivraj Government Polytechnic Ranchi https://orcid.org/0009-0006-5335-5579
Wasim Quraishi National Institute of Advanced Manufacturing Technology (NIAMT)
Subhankar Basu National Institute of Advanced Manufacturing Technology (NIAMT) https://orcid.org/0000-0002-5764-9965

DOI:

https://doi.org/10.36312/esaintika.v7i2.1342

Keywords:

Coagulation, Drinking water treatment, Natural organic matter, Process intensification, Sustainable process

Abstract

Natural organic matter (NOM) seriously challenges the drinking water supply. It typically exists as complex organic substances generated in the natural water ecosystem as part of hydrologic, biological, and geological cycles. The significant variation, composition, and abundance of NOM in natural water or wastewater necessitate the implementation of robust and adaptive technologies, particularly in addressing even more stringent standards of drinking water supply or treated water discharge. Coagulation is one of the most common processes for water and wastewater treatments. It is highly desirable to treat feed containing NOM because it prevents the disinfection of by-products formation. Therefore, current dynamics of NOM in terms of varying compositions and concentrations demand improvement in handling the coagulation process through optimization of operational parameters (dosing and the control of pH), application of novel and more effective coagulants, and as a combination with other processes through process intensification. This review provides a comprehensive analysis of recent literature on developments of coagulation for NOM removal. The coagulants are grouped systematically and assessed. Next, enhanced coagulation via process intensification with other processes (membrane filtration, oxidation, adsorption, and ion exchange) is discussed. Lastly, the future outlook on research direction on sustainable coagulation process is listed to support circular and bioeconomy.

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Author Biography

Subhankar Basu, National Institute of Advanced Manufacturing Technology (NIAMT)

Scopus Id: 35104373400

References

Al-Shannag, M., Bani-Melhem, K., Al-Anber, Z., & Al-Qodah, Z. (2013). Enhancement of COD-Nutrients Removals and Filterability of Secondary Clarifier Municipal Wastewater Influent Using Electrocoagulation Technique. Separation Science and Technology (Philadelphia), 48(4), 673–680. https://doi.org/10.1080/01496395.2012.707729

Al-Wasify, R. S., Al-Sayed, A.-S. A., Saleh, S. M., & Aboelwafa, A. M. (2015). Bacterial exopolysaccharides as new natural coagulants for surface water treatment. International Journal of PharmTech Research, 8(9), 198–207.

Amy, G. (2008). Fundamental understanding of organic matter fouling of membranes. Desalination, 231(1–3), 44–51. https://doi.org/10.1016/j.desal.2007.11.037

Ang, W. L., Mohammad, A. W., Benamor, A., & Hilal, N. (2016). Chitosan as natural coagulant in hybrid coagulation-nanofiltration membrane process for water treatment. Journal of Environmental Chemical Engineering, 4(4), 4857–4862. https://doi.org/10.1016/j.jece.2016.03.029

Ayekoe, C. Y. P., Robert, D., & Lanciné, D. G. (2017). Combination of coagulation-flocculation and heterogeneous photocatalysis for improving the removal of humic substances in real treated water from Agbô River (Ivory-Coast). Catalysis Today, 281, 2–13. https://doi.org/10.1016/j.cattod.2016.09.024

Bahadori, A., Clark, M., & Boyd, B. (2013). Essentials of Water Systems Design in the Oil, Gas, and Chemical Processing Industries. Essentials of Water Systems Design in the Oil, Gas, and Chemical Processing Industries.

Barambu, N. U., Bilad, M. R., Laziz, A. M., Nordin, N. A. H. M., Bustam, M. A., Shamsuddin, N., & Khan, A. L. (2021). A wavy flow channel system for membrane fouling control in oil/water emulsion filtration. Journal of Water Process Engineering, 44. Scopus. https://doi.org/10.1016/j.jwpe.2021.102340

Barambu, N. U., Bilad, M. R., Wibisono, Y., Jaafar, J., Mahlia, T. M. I., & Khan, A. L. (2019). Membrane surface patterning as a fouling mitigation strategy in liquid filtration: A review. Polymers, 11(10). Scopus. https://doi.org/10.3390/polym11101687

Bergamasco, R., Konradt-Moraes, L. C., Vieira, M. F., Fagundes-Klen, M. R., & Vieira, A. M. S. (2011). Performance of a coagulation-ultrafiltration hybrid process for water supply treatment. Chemical Engineering Journal, 166(2), 483–489. https://doi.org/10.1016/j.cej.2010.10.076

Bhatnagar, A., & Sillanpää, M. (2017). Removal of natural organic matter (NOM) and its constituents from water by adsorption – A review. Chemosphere, 166, 497–510. https://doi.org/10.1016/j.chemosphere.2016.09.098

Bilad, M. R. (2017). Membrane bioreactor for domestic wastewater treatment: Principles, challanges and future research directions. Indonesian Journal of Science and Technology, 2(1), 97–123. Scopus. https://doi.org/10.17509/ijost.v2i1.5993

Bilad, M. R., Mezohegyi, G., Declerck, P., & Vankelecom, I. F. J. (2012). Novel magnetically induced membrane vibration (MMV) for fouling control in membrane bioreactors. Water Research, 46(1), 63–72. Scopus. https://doi.org/10.1016/j.watres.2011.10.026

Bolto, B. A., Dixon, D. R., Eldridge, R. J., & King, S. J. (1998). The use of cationic polymers as primary coagulants in water treatment. Chemical Water and Wastewater Treatment V, 171–185.

Bolto, B., Dixon, D., Eldridge, R., King, S., & Linge, K. (2002). Removal of natural organic matter by ion exchange. Water Research, 36(20), 5057–5065. https://doi.org/10.1016/S0043-1354(02)00231-2

Bolto, B., & Gregory, J. (2007). Organic polyelectrolytes in water treatment. Water Research, 41(11), 2301–2324. https://doi.org/10.1016/j.watres.2007.03.012

Boyer, T. H., & Singer, P. C. (2006). A pilot-scale evaluation of magnetic ion exchange treatment for removal of natural organic material and inorganic anions. Water Research, 40(15), 2865–2876. https://doi.org/10.1016/j.watres.2006.05.022

Bratby, J. (2006). Coagulation and Flocculation in Water and Wastewater Treatment.

Budd, G. C., Hess, A. F., Shorney-Darby, H., Neemann, J. J., Spencer, C. M., Bellamy, J. D., & Hargette, P. H. (2004). Coagulation applications for new treatment goals. Journal / American Water Works Association, 96(2), 102-113+12. https://doi.org/10.1002/j.1551-8833.2004.tb10559.x

Calza, P., & Vione, D. (2015). Surface Water Photochemistry. Surface Water Photochemistry.

Cao, B., Gao, B., Liu, X., Wang, M., Yang, Z., & Yue, Q. (2011). The impact of pH on floc structure characteristic of polyferric chloride in a low DOC and high alkalinity surface water treatment. Water Research, 45(18), 6181–6188. https://doi.org/10.1016/j.watres.2011.09.019

Chang, E.-E., Chiang, P.-C., Tang, W.-Y., Chao, S.-H., & Hsing, H.-J. (2005). Effects of polyelectrolytes on reduction of model compounds via coagulation. Chemosphere, 58(8), 1141–1150. Scopus. https://doi.org/10.1016/j.chemosphere.2004.08.008

Chekli, L., Eripret, C., Park, S. H., Tabatabai, S. A. A., Vronska, O., Tamburic, B., Kim, J. H., & Shon, H. K. (2017). Coagulation performance and floc characteristics of polytitanium tetrachloride (PTC) compared with titanium tetrachloride (TiCl4) and ferric chloride (FeCl3) in algal turbid water. Separation and Purification Technology, 175, 99–106. https://doi.org/10.1016/j.seppur.2016.11.019

Chekli, L., Galloux, J., Zhao, Y. X., Gao, B. Y., & Shon, H. K. (2015). Coagulation performance and floc characteristics of polytitanium tetrachloride (PTC) compared with titanium tetrachloride (TiCl4) and iron salts in humic acid-kaolin synthetic water treatment. Separation and Purification Technology, 142, 155–161. https://doi.org/10.1016/j.seppur.2014.12.043

Chellam, S., & Sari, M. A. (2016). Aluminum electrocoagulation as pretreatment during microfiltration of surface water containing NOM: A review of fouling, NOM, DBP, and virus control. Journal of Hazardous Materials, 304, 490–501. https://doi.org/10.1016/j.jhazmat.2015.10.054

Cheng, W. P., & Chi, F. H. (2002). A study of coagulation mechanisms of polyferric sulfate reacting with humic acid using a fluorescence-quenching method. Water Research, 36(18), 4583–4591. https://doi.org/10.1016/S0043-1354(02)00189-6

Cheng, W. P., Chi, F. H., Li, C. C., & Yu, R. F. (2008). A study on the removal of organic substances from low-turbidity and low-alkalinity water with metal-polysilicate coagulants. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 312(2–3), 238–244. Scopus. https://doi.org/10.1016/j.colsurfa.2007.06.060

Cheng, X., Zhou, W., Li, P., Ren, Z., Wu, D., Luo, C., Tang, X., Wang, J., & Liang, H. (2019). Improving ultrafiltration membrane performance with pre-deposited carbon nanotubes/nanofibers layers for drinking water treatment. Chemosphere, 234, 545–557. Scopus. https://doi.org/10.1016/j.chemosphere.2019.06.090

Chiang, P. C., Chang, E., & Liang, C. H. (2002). NOM characteristics and treatabilities of ozonation processes. Chemosphere, 46(6), 929–936. https://doi.org/10.1016/S0045-6535(01)00181-3

Chun, Y., Mulcahy, D., Zou, L., & Kim, I. S. (2017). A Short Review of Membrane Fouling in Forward Osmosis Processes. Membranes, 7(2). https://doi.org/10.3390/membranes7020030

Comninellis, C., & Chen, G. (2010). Electrochemistry for the environment (p. 563). https://doi.org/10.1007/978-0-387-68318-8

Cornelissen, E. R., Moreau, N., Siegers, W. G., Abrahamse, A. J., Rietveld, L. C., Grefte, A., Dignum, M., Amy, G., & Wessels, L. P. (2008). Selection of anionic exchange resins for removal of natural organic matter (NOM) fractions. Water Research, 42(1–2), 413–423. https://doi.org/10.1016/j.watres.2007.07.033

Crittenden, J. C., Trussell, Hand, D. W., Howe, K. J., & Tchobanoglous, G. (2012). MWH’s Water Treatment: Principles and Design: Third Edition. https://doi.org/10.1002/9781118131473

Davis, C. C., & Edwards, M. (2014). Coagulation with hydrolyzing metal salts: Mechanisms and water quality impacts. Critical Reviews in Environmental Science and Technology, 44(4), 303–347. https://doi.org/10.1080/10643389.2012.718947

Demirci, Y., Pekel, L. C., & Alpbaz, M. (2015). Investigation of different electrode connections in electrocoagulation of textile wastewater treatment. International Journal of Electrochemical Science, 10(3), 2685–2693.

Dermouchi, A., Bencheikh-Lehocine, M., Arris, S., Nedeff, V., & Bârsan, N. (2015). Aspects regarding the electrocoagulation applications in the water and wastewater treatment. Journal of Engineering Studies and Research, 21, 26–33.

Dewi, R., Shamsuddin, N., Abu Bakar, M. S., Santos, J. H., Bilad, M. R., & Lim, L. H. (2021). Progress in emerging contaminants removal by adsorption/membrane filtration-based technologies: A review. Indonesian Journal of Science and Technology, 6(3), 577–618. Scopus. https://doi.org/10.17509/ijost.v6i3.39271

Ding, L., Wu, C., Deng, H., & Zhang, X. (2012). Adsorptive characteristics of phosphate from aqueous solutions by MIEX resin. Journal of Colloid and Interface Science, 376(1), 224–232. https://doi.org/10.1016/j.jcis.2012.03.002

Discart, V., Bilad, M. R., Van Nevel, S., Boon, N., Cromphout, J., & Vankelecom, I. F. J. (2014). Role of transparent exopolymer particles on membrane fouling in a full-scale ultrafiltration plant: Feed parameter analysis and membrane autopsy. Bioresource Technology, 173, 67–74. Scopus. https://doi.org/10.1016/j.biortech.2014.08.098

Discart, V., Bilad, M. R., Vandamme, D., Foubert, I., Muylaert, K., & Vankelecom, I. F. J. (2012). Direct role of transparent exopolymeric particles (TEP) on membrane fouling of micro- And ultrafiltration. 44, 537–538. Scopus. https://doi.org/10.1016/j.proeng.2012.08.478

Discart, V., Bilad, M. R., & Vankelecom, I. F. J. (2015). Critical evaluation of the determination methods for transparent exopolymer particles, agents of membrane fouling. Critical Reviews in Environmental Science and Technology, 45(2), 167–192. Scopus. https://doi.org/10.1080/10643389.2013.829982

Drikas, M., Dixon, M., & Morran, J. (2011). Long term case study of MIEX pre-treatment in drinking water; understanding NOM removal. Water Research, 45(4), 1539–1548. https://doi.org/10.1016/j.watres.2010.11.024

Duan, J., & Gregory, J. (2003). Coagulation by hydrolysing metal salts. Advances in Colloid and Interface Science, 100–102(SUPPL.), 475–502. https://doi.org/10.1016/S0001-8686(02)00067-2

Dubrawski, K. L., & Mohseni, M. (2013a). In-situ identification of iron electrocoagulation speciation and application for natural organic matter (NOM) removal. Water Research, 47(14), 5371–5380. https://doi.org/10.1016/j.watres.2013.06.021

Dubrawski, K. L., & Mohseni, M. (2013b). Standardizing electrocoagulation reactor design: Iron electrodes for NOM removal. Chemosphere, 91(1), 55–60. https://doi.org/10.1016/j.chemosphere.2012.11.075

Fitzpatrick, C. S. B., Fradin, E., & Gregory, J. (2004). Temperature effects on flocculation, using different coagulants. Water Science and Technology, 50(12), 171–175. https://doi.org/10.2166/wst.2004.0710

Flaten, T. P. (2001). Aluminium as a risk factor in Alzheimer’s disease, with emphasis on drinking water. Brain Research Bulletin, 55(2), 187–196. https://doi.org/10.1016/S0361-9230(01)00459-2

Gao, B.-Y., Wang, Y., Yue, Q.-Y., Wei, J.-C., & Li, Q. (2008). The size and coagulation behavior of a novel composite inorganic-organic coagulant. Separation and Purification Technology, 62(3), 544–550. https://doi.org/10.1016/j.seppur.2008.02.023

Gkotsis, P. K., Batsari, E. L., Peleka, E. N., Tolkou, A. K., & Zouboulis, A. I. (2017). Fouling control in a lab-scale MBR system: Comparison of several commercially applied coagulants. Journal of Environmental Management, 203, 838–846. https://doi.org/10.1016/j.jenvman.2016.03.003

Golea, D. M., Upton, A., Jarvis, P., Moore, G., Sutherland, S., Parsons, S. A., & Judd, S. J. (2017). THM and HAA formation from NOM in raw and treated surface waters. Water Research, 112, 226–235. https://doi.org/10.1016/j.watres.2017.01.051

Gong, G., Zhao, Y., Zhang, Y., Deng, B., Liu, W., Wang, M., Yuan, X., & Xu, L. (2020). Establishment of a molecular structure model for classified products of coal-based fulvic acid. Fuel, 267, 117210. https://doi.org/10.1016/j.fuel.2020.117210

Gonzalez-Torres, A., Putnam, J., Jefferson, B., Stuetz, R. M., & Henderson, R. K. (2014). Examination of the physical properties of Microcystis aeruginosa flocs produced on coagulation with metal salts. Water Research, 60, 197–209. https://doi.org/10.1016/j.watres.2014.04.046

Goslan, E. H., Seigle, C., Purcell, D., Henderson, R., Parsons, S. A., Jefferson, B., & Judd, S. J. (2017). Carbonaceous and nitrogenous disinfection by-product formation from algal organic matter. Chemosphere, 170, 1–9. https://doi.org/10.1016/j.chemosphere.2016.11.148

Graham, N., Gang, F., Fowler, G., & Watts, M. (2008). Characterisation and coagulation performance of a tannin-based cationic polymer: A preliminary assessment. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 327(1–3), 9–16. https://doi.org/10.1016/j.colsurfa.2008.05.045

Gregory, J., & Duan, J. (2001). Hydrolyzing metal salts as coagulants. Pure and Applied Chemistry, 73(12), 2017–2026. https://doi.org/10.1351/pac200173122017

Guo, H., Wyart, Y., Perot, J., Nauleau, F., & Moulin, P. (2010). Low-pressure membrane integrity tests for drinking water treatment: A review. Water Research, 44(1), 41–57. https://doi.org/10.1016/j.watres.2009.09.032

Han, N., Huang, G., An, C., Zhao, S., Yao, Y., Fu, H., & Li, W. (2015). Removal of sulfonated humic acid through a hybrid electrocoagulation-ultrafiltration process. Industrial and Engineering Chemistry Research, 54(21), 5793–5801. https://doi.org/10.1021/acs.iecr.5b00949

Hanafi, F., Assobhei, O., & Mountadar, M. (2010). Detoxification and discoloration of Moroccan olive mill wastewater by electrocoagulation. Journal of Hazardous Materials, 174(1–3), 807–812. https://doi.org/10.1016/j.jhazmat.2009.09.124

Heiderscheidt, E., Leiviskä, T., & Kløve, B. (2016). Coagulation of humic waters for diffused pollution control and the influence of coagulant type on DOC fractions removed. Journal of Environmental Management, 181, 883–893. https://doi.org/10.1016/j.jenvman.2016.06.043

Henderson, R., Sharp, E., Jarvis, P., Parsons, S., & Jefferson, B. (2006). Identifying the linkage between particle characteristics and understanding coagulation performance. Water Science and Technology: Water Supply, 6(1), 31–38. https://doi.org/10.2166/ws.2006.005

Her, N., Amy, G., Park, H.-R., & Song, M. (2004). Characterizing algogenic organic matter (AOM) and evaluating associated NF membrane fouling. Water Research, 38(6), 1427–1438. https://doi.org/10.1016/j.watres.2003.12.008

Hirabayashi, Y., Kanae, S., Emori, S., Oki, T., & Kimoto, M. (2008). Global projections of changing risks of floods and droughts in a changing climate. Hydrological Sciences Journal, 53(4), 754–772. https://doi.org/10.1623/hysj.53.4.754

Hu, C., Wang, S., Sun, J., Liu, H., & Qu, J. (2016). An effective method for improving electrocoagulation process: Optimization of Al13 polymer formation. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 489, 234–240. https://doi.org/10.1016/j.colsurfa.2015.10.063

Hu, W. C., Wu, C. D., Jia, A. Y., & Chen, F. (2015). Enhanced coagulation for treating slightly polluted algae-containing raw water of the Pearl River combining ozone pre-oxidation with polyaluminum chloride (PAC). Desalination and Water Treatment, 56(6), 1698–1703. https://doi.org/10.1080/19443994.2014.954003

Huang, W., He, H., Dong, B., Chu, H., Xu, G., & Yan, Z. (2015). Effects of macro-porous anion exchange and coagulation treatment on organic removal and membrane fouling reduction in water treatment. Desalination, 355, 204–216. https://doi.org/10.1016/j.desal.2014.10.045

Huang, X., Gao, B., Rong, H., Yue, Q., Zhang, Y., & Teng, P. (2015). Effect of using polydimethyldiallylammonium chloride as coagulation aid on polytitanium salt coagulation performance, floc properties and sludge reuse. Separation and Purification Technology, 143, 64–71. https://doi.org/10.1016/j.seppur.2015.01.024

Huang, X., Gao, B., Zhao, S., Sun, S., Yue, Q., Wang, Y., & Li, Q. (2016). Application of titanium sulfate in a coagulation-ultrafiltration process: A comparison with aluminum sulfate and ferric sulfate. RSC Advances, 6(55), 49469–49477. https://doi.org/10.1039/c6ra05075a

Hudson, N., Baker, A., & Reynolds, D. (2007). Fluorescence analysis of dissolved organic matter in natural, waste and polluted waters—A review. River Research and Applications, 23(6), 631–649. https://doi.org/10.1002/rra.1005

Humbert, H., Gallard, H., Jacquemet, V., & Croué, J.-P. (2007). Combination of coagulation and ion exchange for the reduction of UF fouling properties of a high DOC content surface water. Water Research, 41(17), 3803–3811. https://doi.org/10.1016/j.watres.2007.06.009

Humbert, H., Gallard, H., Suty, H., & Croué, J.-P. (2008). Natural organic matter (NOM) and pesticides removal using a combination of ion exchange resin and powdered activated carbon (PAC). Water Research, 42(6–7), 1635–1643. https://doi.org/10.1016/j.watres.2007.10.012

Hussain, S., van Leeuwen, J., Chow, C., Beecham, S., Kamruzzaman, M., Wang, D., Drikas, M., & Aryal, R. (2013). Removal of organic contaminants from river and reservoir waters by three different aluminum-based metal salts: Coagulation adsorption and kinetics studies. Chemical Engineering Journal, 225, 394–405. https://doi.org/10.1016/j.cej.2013.03.119

Hussain, S., van Leeuwen, J., Chow, C. W. K., Aryal, R., Beecham, S., Duan, J., & Drikas, M. (2014). Comparison of the coagulation performance of tetravalent titanium and zirconium salts with alum. Chemical Engineering Journal, 254, 635–646. https://doi.org/10.1016/j.cej.2014.06.014

Ibrahim, N., & Aziz, H. A. (2014). Trends on natural organic matter in drinking water sources and its treatment. Int. J. Sci. Res. Environ. Sci., 2(3), 94–106.

Jarvis, P., Jefferson, B., & Parsons, S. A. (2006). Floc structural characteristics using conventional coagulation for a high doc, low alkalinity surface water source. Water Research, 40(14), 2727–2737. https://doi.org/10.1016/j.watres.2006.04.024

Jarvis, P., Sharp, E., Pidou, M., Molinder, R., Parsons, S. A., & Jefferson, B. (2012). Comparison of coagulation performance and floc properties using a novel zirconium coagulant against traditional ferric and alum coagulants. Water Research, 46(13), 4179–4187. https://doi.org/10.1016/j.watres.2012.04.043

Jiang, J. Q., & Graham, N. J. D. (1996). Enhanced coagulation using al/fe(iii) coagulants: Effect of coagulant chemistry on the removal of colour-causing nom. Environmental Technology (United Kingdom), 17(9), 937–950. https://doi.org/10.1080/09593330.1996.9618422

Jiang, J.-Q. (2015). The role of coagulation in water treatment. Current Opinion in Chemical Engineering, 8, 36–44. https://doi.org/10.1016/j.coche.2015.01.008

Jiang, J.-Q., & Graham, N. J. D. (1998). Pre-polymerised inorganic coagulants and phosphorus removal by coagulation—A review. Water SA, 24(3), 237–244.

Jiang, Y., Goodwill, J. E., Tobiason, J. E., & Reckhow, D. A. (2016). Impacts of ferrate oxidation on natural organic matter and disinfection byproduct precursors. Water Research, 96, 114–125. https://doi.org/10.1016/j.watres.2016.03.052

Joseph, L., Flora, J. R. V., Park, Y.-G., Badawy, M., Saleh, H., & Yoon, Y. (2012). Removal of natural organic matter from potential drinking water sources by combined coagulation and adsorption using carbon nanomaterials. Separation and Purification Technology, 95, 64–72. https://doi.org/10.1016/j.seppur.2012.04.033

Jung, C., Phal, N., Oh, J., Chu, K. H., Jang, M., & Yoon, Y. (2015). Removal of humic and tannic acids by adsorption-coagulation combined systems with activated biochar. Journal of Hazardous Materials, 300, 808–814. https://doi.org/10.1016/j.jhazmat.2015.08.025

Keeley, J., Jarvis, P., & Judd, S. J. (2012). An economic assessment of coagulant recovery from water treatment residuals. Desalination, 287, 132–137. https://doi.org/10.1016/j.desal.2011.09.013

Keeley, J., Jarvis, P., Smith, A. D., & Judd, S. J. (2016). Coagulant recovery and reuse for drinking water treatment. Water Research, 88, 502–509. https://doi.org/10.1016/j.watres.2015.10.038

Kharraz, J. A., Bilad, M. R., & Arafat, H. A. (2015). Simple and effective corrugation of PVDF membranes for enhanced MBR performance. Journal of Membrane Science, 475, 91–100. Scopus. https://doi.org/10.1016/j.memsci.2014.10.018

Kim, H.-C. (2015a). In-line coagulation with quaternary amine polymer prior to microfiltration of humic-rich water. Journal of Colloid and Interface Science, 459, 151–159. Scopus. https://doi.org/10.1016/j.jcis.2015.08.021

Kim, H.-C. (2015b). Microfiltration of humic-rich water coagulated with cationic polymer: The effects of particle characteristics on the membrane performance. Journal of Membrane Science, 475, 349–356. Scopus. https://doi.org/10.1016/j.memsci.2014.10.041

Kitis, M., Ilker Harman, B., Yigit, N. O., Beyhan, M., Nguyen, H., & Adams, B. (2007). The removal of natural organic matter from selected Turkish source waters using magnetic ion exchange resin (MIEX®). Reactive and Functional Polymers, 67(12 SPEC. ISS.), 1495–1504. Scopus. https://doi.org/10.1016/j.reactfunctpolym.2007.07.037

Knauer, K., Homazava, N., Junghans, M., & Wernerz, I. (2017). The influence of particles on bioavailability and toxicity of pesticides in surface water. Integrated Environmental Assessment and Management, 13(4), 585–600. Scopus. https://doi.org/10.1002/ieam.1867

Kristiana, I., Joll, C., & Heitz, A. (2011). Powdered activated carbon coupled with enhanced coagulation for natural organic matter removal and disinfection by-product control: Application in a Western Australian water treatment plant. Chemosphere, 83(5), 661–667. Scopus. https://doi.org/10.1016/j.chemosphere.2011.02.017

Kvinnesland, T., & Ødegaard, H. (2004). The effects of polymer characteristics on nano particle separation in humic substances removal by cationic polymer coagulation. Water Science and Technology, 50(12), 185–191. Scopus. https://doi.org/10.2166/wst.2004.0712

Li, J., Moe, B., Vemula, S., Wang, W., & Li, X.-F. (2016). Emerging Disinfection Byproducts, Halobenzoquinones: Effects of Isomeric Structure and Halogen Substitution on Cytotoxicity, Formation of Reactive Oxygen Species, and Genotoxicity. Environmental Science and Technology, 50(13), 6744–6752. Scopus. https://doi.org/10.1021/acs.est.5b05585

Li, M., Wu, G., Guan, Y., & Zhang, X. (2011). Treatment of river water by a hybrid coagulation and ceramic membrane process. Desalination, 280(1–3), 114–119. Scopus. https://doi.org/10.1016/j.desal.2011.06.059

Listiarini, K., Tor, J. T., Sun, D. D., & Leckie, J. O. (2010). Hybrid coagulation-nanofiltration membrane for removal of bromate and humic acid in water. Journal of Membrane Science, 365(1–2), 154–159. Scopus. https://doi.org/10.1016/j.memsci.2010.08.048

Liu, J., & Zhang, X. (2014). Comparative toxicity of new halophenolic DBPs in chlorinated saline wastewater effluents against a marine alga: Halophenolic DBPs are generally more toxic than haloaliphatic ones. Water Research, 65, 64–72. Scopus. https://doi.org/10.1016/j.watres.2014.07.024

Malaeb, L., & Ayoub, G. M. (2011). Reverse osmosis technology for water treatment: State of the art review. Desalination, 267(1), 1–8. Scopus. https://doi.org/10.1016/j.desal.2010.09.001

Malakootian, M., Mansoorian, H. J., & Moosazadeh, M. (2010). Performance evaluation of electrocoagulation process using iron-rod electrodes for removing hardness from drinking water. Desalination, 255(1–3), 67–71. Scopus. https://doi.org/10.1016/j.desal.2010.01.015

Mao, J., Cao, X., Olk, D. C., Chu, W., & Schmidt-Rohr, K. (2017). Advanced solid-state NMR spectroscopy of natural organic matter. Progress in Nuclear Magnetic Resonance Spectroscopy, 100, 17–51. Scopus. https://doi.org/10.1016/j.pnmrs.2016.11.003

Matilainen, A., Lindqvist, N., & Tuhkanen, T. (2005). Comparison of the efficiency of aluminium and ferric sulphate in the removal of natural organic matter during drinking water treatment process. Environmental Technology, 26(8), 867–876. Scopus. https://doi.org/10.1080/09593332608618502

Matilainen, A., & Sillanpää, M. (2010). Removal of natural organic matter from drinking water by advanced oxidation processes. Chemosphere, 80(4), 351–365. Scopus. https://doi.org/10.1016/j.chemosphere.2010.04.067

Matilainen, A., Vepsäläinen, M., & Sillanpää, M. (2010). Natural organic matter removal by coagulation during drinking water treatment: A review. Advances in Colloid and Interface Science, 159(2), 189–197. https://doi.org/10.1016/j.cis.2010.06.007

Mergen, M. R. D., Jefferson, B., Parsons, S. A., & Jarvis, P. (2008). Magnetic ion-exchange resin treatment: Impact of water type and resin use. Water Research, 42(8–9), 1977–1988. Scopus. https://doi.org/10.1016/j.watres.2007.11.032

Metcalfe, D., Rockey, C., Jefferson, B., Judd, S., & Jarvis, P. (2015). Removal of disinfection by-product precursors by coagulation and an innovative suspended ion exchange process. Water Research, 87, 20–28. Scopus. https://doi.org/10.1016/j.watres.2015.09.003

Metsämuuronen, S., Sillanpää, M., Bhatnagar, A., & Mänttäri, M. (2014). Natural organic matter removal from drinking water by membrane technology. Separation and Purification Reviews, 43(1), 1–61. Scopus. https://doi.org/10.1080/15422119.2012.712080

Mirza, Mohd. A., Agarwal, S. P., Rahman, Md. A., Rauf, A., Ahmad, N., Alam, A., & Iqbal, Z. (2011). Role of humic acid on oral drug delivery of an antiepileptic drug. Drug Development and Industrial Pharmacy, 37(3), 310–319. https://doi.org/10.3109/03639045.2010.512011

Ncibi, M. C., Mahjoub, B., Mahjoub, O., & Sillanpää, M. (2017). Remediation of Emerging Pollutants in Contaminated Wastewater and Aquatic Environments: Biomass-Based Technologies. Clean - Soil, Air, Water, 45(5). Scopus. https://doi.org/10.1002/clen.201700101

Ng, M., Liu, S., Chow, C. W. K., Drikas, M., Amal, R., & Lim, M. (2013). Understanding effects of water characteristics on natural organic matter treatability by PACl and a novel PACl-chitosan coagulants. Journal of Hazardous Materials, 263, 718–725. Scopus. https://doi.org/10.1016/j.jhazmat.2013.10.036

Nguyen, T. V., Zhang, R., Vigneswaran, S., Ngo, H. H., Kandasamy, J., & Mathes, P. (2011). Removal of organic matter from effluents by Magnetic Ion Exchange (MIEX®). Desalination, 276(1–3), 96–102. Scopus. https://doi.org/10.1016/j.desal.2011.03.028

Nissinen, T. K., Miettinen, I. T., Martikainen, P. J., & Vartiainen, T. (2001). Molecular size distribution of natural organic matter in raw and drinking waters. Chemosphere, 45(6–7), 865–873. Scopus. https://doi.org/10.1016/S0045-6535(01)00103-5

Nozaic, D. J., Freese, S. D., & Thompson, P. (2001). Longterm experience in the use of polymeric coagulants at Umgeni water. Water Science and Technology: Water Supply, 1(1), 43–50. Scopus. https://doi.org/10.2166/ws.2001.0006

Ntwampe, I. O., Waanders, F. B., & Bunt, J. R. (2016). Reactivity of Fe salts in the destabilization of acid mine drainage employing mixing and shaking techniques without pH adjustment. International Journal of Mineral Processing, 146, 65–73. Scopus. https://doi.org/10.1016/j.minpro.2015.11.009

Okour, Y., Shon, H. K., & El Saliby, I. (2009). Characterisation of titanium tetrachloride and titanium sulfate flocculation in wastewater treatment. Water Science and Technology, 59(12), 2463–2473. Scopus. https://doi.org/10.2166/wst.2009.254

Oladoja, N. A. (2016). Advances in the quest for substitute for synthetic organic polyelectrolytes as coagulant aid in water and wastewater treatment operations. Sustainable Chemistry and Pharmacy, 3, 47–58. Scopus. https://doi.org/10.1016/j.scp.2016.04.001

Osman, A., Nawi, N. I. M., Samsuri, S., Bilad, M. R., Shamsuddin, N., Khan, A. L., Jaafar, J., & Nordin, N. A. H. (2020). Patterned membrane in an energy-efficient tilted panel filtration system for fouling control in activated sludge filtration. Polymers, 12(2). Scopus. https://doi.org/10.3390/polym12020432

Park, S. -j., & Yoon, T. -i. (2009). Effects of iron species and inert minerals on coagulation and direct filtration for humic acid removal. Desalination, 239(1–3), 146–158. Scopus. https://doi.org/10.1016/j.desal.2008.03.015

Pernitsky, D. J., & Edzwald, J. K. (2006). Selection of alum and polyaluminum coagulants: Principles and applications. Journal of Water Supply: Research and Technology - AQUA, 55(2), 121–141. Scopus. https://doi.org/10.2166/aqua.2006.062

Pivokonsky, M., Naceradska, J., Brabenec, T., Novotna, K., Baresova, M., & Janda, V. (2015). The impact of interactions between algal organic matter and humic substances on coagulation. Water Research, 84, 278–285. Scopus. https://doi.org/10.1016/j.watres.2015.07.047

Pourrezaei, P., Drzewicz, P., Wang, Y., Gamal El-Din, M., Perez-Estrada, L. A., Martin, J. W., Anderson, J., Wiseman, S., Liber, K., & Giesy, J. P. (2011). The impact of metallic coagulants on the removal of organic compounds from oil sands process-affected water. Environmental Science and Technology, 45(19), 8452–8459. Scopus. https://doi.org/10.1021/es201498v

Qi, S., & Schideman, L. C. (2008). An overall isotherm for activated carbon adsorption of dissolved natural organic matter in water. Water Research, 42(13), 3353–3360. Scopus. https://doi.org/10.1016/j.watres.2008.04.016

Rahmawati, R., Bilad, M. R., Laziz, A. M., Nordin, N. A. H. M., Jusoh, N., Putra, Z. A., Mahlia, T. M. I., & Jaafar, J. (2019). Finned spacer for efficient membrane fouling control in produced water filtration. Journal of Environmental Management, 249. Scopus. https://doi.org/10.1016/j.jenvman.2019.109359

Rahmawati, R., Bilad, M. R., Nawi, N. I. M., Wibisono, Y., Suhaimi, H., Shamsuddin, N., & Arahman, N. (2021). Engineered spacers for fouling mitigation in pressure driven membrane processes: Progress and projection. Journal of Environmental Chemical Engineering, 9(5). Scopus. https://doi.org/10.1016/j.jece.2021.106285

Renault, F., Sancey, B., Badot, P.-M., & Crini, G. (2009). Chitosan for coagulation/flocculation processes—An eco-friendly approach. European Polymer Journal, 45(5), 1337–1348. https://doi.org/10.1016/j.eurpolymj.2008.12.027

Rodríguez, F. J., Marcos, L. A., Núñez, L. A., & García, M. (2012). Effects of Ozonation on Molecular Weight Distribution of Humic Substances and Coagulation Processes—A Case Study: The Úzquiza Reservoir Water. Ozone: Science and Engineering, 34(5), 342–353. Scopus. https://doi.org/10.1080/01919512.2012.710874

Sadri Moghaddam, S., Alavi Moghaddam, M. R., & Arami, M. (2010). Coagulation/flocculation process for dye removal using sludge from water treatment plant: Optimization through response surface methodology. Journal of Hazardous Materials, 175(1–3), 651–657. Scopus. https://doi.org/10.1016/j.jhazmat.2009.10.058

Santschi, P. H., Xu, C., Zhang, S., Schwehr, K. A., Lin, P., Yeager, C. M., & Kaplan, D. I. (2017). Recent advances in the detection of specific natural organic compounds as carriers for radionuclides in soil and water environments, with examples of radioiodine and plutonium. Journal of Environmental Radioactivity, 171, 226–233. Scopus. https://doi.org/10.1016/j.jenvrad.2017.02.023

Särkkä, H., Vepsäläinen, M., & Sillanpää, M. (2015). Natural organic matter (NOM) removal by electrochemical methods—A review. Journal of Electroanalytical Chemistry, 755, 100–108. Scopus. https://doi.org/10.1016/j.jelechem.2015.07.029

Sharp, E. L., Parsons, S. A., & Jefferson, B. (2006). Seasonal variations in natural organic matter and its impact on coagulation in water treatment. Science of the Total Environment, 363(1–3), 183–194. Scopus. https://doi.org/10.1016/j.scitotenv.2005.05.032

Shen, X., Gao, B., Huang, X., Bu, F., Yue, Q., Li, R., & Jin, B. (2017). Effect of the dosage ratio and the viscosity of PAC/PDMDAAC on coagulation performance and membrane fouling in a hybrid coagulation-ultrafiltration process. Chemosphere, 173, 288–298. Scopus. https://doi.org/10.1016/j.chemosphere.2017.01.074

Sillanpää, M. (2014). Natural Organic Matter in Water: Characterization and Treatment Methods (p. 367). Scopus. https://doi.org/10.1016/C2013-0-19213-6

Sillanpää, M., Ncibi, M. C., Matilainen, A., & Vepsäläinen, M. (2018). Removal of natural organic matter in drinking water treatment by coagulation: A comprehensive review. Chemosphere, 190, 54–71. https://doi.org/10.1016/j.chemosphere.2017.09.113

Singer, P. C., & Bilyk, K. (2002). Enhanced coagulation using a magnetic ion exchange resin. Water Research, 36(16), 4009–4022. Scopus. https://doi.org/10.1016/S0043-1354(02)00115-X

Song, Y., Hahn, H. H., & Hoffmann, E. (2002). Effects of pH and Ca/P ratio on the precipitation of phosphate. Chemical Water and Wastewater Treatment., 7, 349–362.

Sun, C., Yue, Q., Gao, B., Mu, R., Liu, J., Zhao, Y., Yang, Z., & Xu, W. (2011). Effect of pH and shear force on flocs characteristics for humic acid removal using polyferric aluminum chloride-organic polymer dual-coagulants. Desalination, 281(1), 243–247. Scopus. https://doi.org/10.1016/j.desal.2011.07.065

Sun, W., Nan, J., Yao, M., Xing, J., & Tian, J. (2016). Effect of aluminum speciation on fouling mechanisms by pre-coagulation/ultrafiltration process with different NOM fractions. Environmental Science and Pollution Research, 23(17), 17459–17473. Scopus. https://doi.org/10.1007/s11356-016-6928-2

Sutzkover-Gutman, I., & Hasson, D. (2010). Feed water pretreatment for desalination plants. Desalination, 264(3), 289–296. https://doi.org/10.1016/j.desal.2010.07.014

Tang, W.-W., Zeng, G.-M., Gong, J.-L., Liang, J., Xu, P., Zhang, C., & Huang, B.-B. (2014). Impact of humic/fulvic acid on the removal of heavy metals from aqueous solutions using nanomaterials: A review. Science of the Total Environment, 468–469, 1014–1027. Scopus. https://doi.org/10.1016/j.scitotenv.2013.09.044

Tubi?, A., Agbaba, J., Dalmacija, B., Molnar, J., Maleti?, S., Watson, M., & Perovi?, S. U. (2013). Insight into changes during coagulation in NOM reactivity for trihalomethanes and haloacetic acids formation. Journal of Environmental Management, 118, 153–160. Scopus. https://doi.org/10.1016/j.jenvman.2012.11.046

Ulu, F., Bari?çi, S., Kobya, M., & Sillanpää, M. (2015). An evaluation on different origins of natural organic matters using various anodes by electrocoagulation. Chemosphere, 125, 108–114. Scopus. https://doi.org/10.1016/j.chemosphere.2014.11.063

Umar, M., Roddick, F., & Fan, L. (2016). Comparison of coagulation efficiency of aluminium and ferric-based coagulants as pre-treatment for UVC/H2O2 treatment of wastewater RO concentrate. Chemical Engineering Journal, 284, 841–849. Scopus. https://doi.org/10.1016/j.cej.2015.08.109

Upton, W. V., & Buswell, A. M. (1937). Titanium Salts in Water Purification. Industrial and Engineering Chemistry, 29(8), 870–871. Scopus. https://doi.org/10.1021/ie50332a006

Uyak, V., & Toroz, I. (2007). Disinfection by-product precursors reduction by various coagulation techniques in Istanbul water supplies. Journal of Hazardous Materials, 141(1), 320–328. Scopus. https://doi.org/10.1016/j.jhazmat.2006.07.007

Vepsäläinen, M., Ghiasvand, M., Selin, J., Pienimaa, J., Repo, E., Pulliainen, M., & Sillanpää, M. (2009). Investigations of the effects of temperature and initial sample pH on natural organic matter (NOM) removal with electrocoagulation using response surface method (RSM). Separation and Purification Technology, 69(3), 255–261. Scopus. https://doi.org/10.1016/j.seppur.2009.08.001

Vepsäläinen, M., Pulliainen, M., & Sillanpää, M. (2012). Effect of electrochemical cell structure on natural organic matter (NOM) removal from surface water through electrocoagulation (EC). Separation and Purification Technology, 99, 20–27. Scopus. https://doi.org/10.1016/j.seppur.2012.08.011

Volk, C., Bell, K., Ibrahim, E., Verges, D., Amy, G., & Lechevallier, M. (2000). Impact of enhanced and optimized coagulation on removal of organic matter and its biodegradable fraction in drinking water. Water Research, 34(12), 3247–3257. Scopus. https://doi.org/10.1016/S0043-1354(00)00033-6

Wan, W., Pepping, T. J., Banerji, T., Chaudhari, S., & Giammar, D. E. (2011). Effects of water chemistry on arsenic removal from drinking water by electrocoagulation. Water Research, 45(1), 384–392. Scopus. https://doi.org/10.1016/j.watres.2010.08.016

Wang, H., Keller, A. A., & Li, F. (2010). Natural organic matter removal by adsorption onto carbonaceous nanoparticles and coagulation. Journal of Environmental Engineering, 136(10), 1075–1081. Scopus. https://doi.org/10.1061/(ASCE)EE.1943-7870.0000247

Wang, J., Xu, W., Xu, J., Wei, D., Feng, H., & Xu, Z. (2016). Effect of aluminum speciation and pH on in-line coagulation/diatomite microfiltration process: Correlations between aggregate characteristics and membrane fouling. Journal of Molecular Liquids, 224, 492–501. Scopus. https://doi.org/10.1016/j.molliq.2016.10.015

Wang, S., Liu, C., & Li, Q. (2013). Impact of polymer flocculants on coagulation-microfiltration of surface water. Water Research, 47(13), 4538–4546. Scopus. https://doi.org/10.1016/j.watres.2013.04.040

Wang, Z., Nan, J., Yao, M., Yang, Y., & Zhang, X. (2017). Insight into the combined coagulation-ultrafiltration process: The role of Al species of polyaluminum chlorides. Journal of Membrane Science, 529, 80–86. Scopus. https://doi.org/10.1016/j.memsci.2017.01.061

Watson, K., Farré, M. J., & Knight, N. (2015). Enhanced coagulation with powdered activated carbon or MIEX® secondary treatment: A comparison of disinfection by-product formation and precursor removal. Water Research, 68, 454–466. Scopus. https://doi.org/10.1016/j.watres.2014.09.042

Wei, J. C., Gao, B. Y., Yue, Q. Y., Wang, Y., & Lu, L. (2009). Performance and mechanism of polyferric-quaternary ammonium salt composite flocculants in treating high organic matter and high alkalinity surface water. Journal of Hazardous Materials, 165(1–3), 789–795. Scopus. https://doi.org/10.1016/j.jhazmat.2008.10.069

Wei, Y., Dong, X., Ding, A., & Xie, D. (2016). Characterization and coagulation-flocculation behavior of an inorganic polymer coagulant—Poly-ferric-zinc-sulfate. Journal of the Taiwan Institute of Chemical Engineers, 58, 351–356. Scopus. https://doi.org/10.1016/j.jtice.2015.06.004

Wibisono, Y., & Bilad, M. R. (2019). Design of forward osmosis system. In Current Trends and Future Developments on (Bio-) Membranes: Reverse and Forward Osmosis: Principles, Applications, Advances (pp. 57–83). Scopus. https://doi.org/10.1016/B978-0-12-816777-9.00003-4

Wu, X., Tan, X., Yang, S., Wen, T., Guo, H., Wang, X., & Xu, A. (2013). Coexistence of adsorption and coagulation processes of both arsenate and NOM from contaminated groundwater by nanocrystallined Mg/Al layered double hydroxides. Water Research, 47(12), 4159–4168. Scopus. https://doi.org/10.1016/j.watres.2012.11.056

Xu, J., Xu, W., Wang, D., Sang, G., & Yang, X. (2016). Evaluation of enhanced coagulation coupled with magnetic ion exchange (MIEX) in natural organic matter and sulfamethoxazole removals: The role of Al-based coagulant characteristic. Separation and Purification Technology, 167, 70–78. Scopus. https://doi.org/10.1016/j.seppur.2016.05.007

Xu, Y., Chen, T., Liu, Z., Zhu, S., Cui, F., & Shi, W. (2016). The impact of recycling alum-humic-floc (AHF) on the removal of natural organic materials (NOM): Behavior of coagulation and adsorption. Chemical Engineering Journal, 284, 1049–1057. Scopus. https://doi.org/10.1016/j.cej.2015.09.069

Xu, Z., Jiao, R., Liu, H., Wang, D., Chow, C. W. K., & Drikas, M. (2013). Hybrid treatment process of using MIEX and high performance composite coagulant for DOM and bromide removal. Journal of Environmental Engineering (United States), 139(1), 79–85. Scopus. https://doi.org/10.1061/(ASCE)EE.1943-7870.0000622

Yan, M., Wang, D., Ni, J., Qu, J., Ni, W., & Van Leeuwen, J. (2009). Natural organic matter (NOM) removal in a typical North-China water plant by enhanced coagulation: Targets and techniques. Separation and Purification Technology, 68(3), 320–327. Scopus. https://doi.org/10.1016/j.seppur.2009.05.021

Yang, M., & Zhang, X. (2013). Comparative developmental toxicity of new aromatic halogenated DBPs in a chlorinated saline sewage effluent to the marine polychaete platynereis dumerilii. Environmental Science and Technology, 47(19), 10868–10876. Scopus. https://doi.org/10.1021/es401841t

Yee, L. F., Abdullah, P. M., Abdullah, A., Ishak, B., & Abidin, K. N. Z. (2009). Hydrophobicity characteristics of natural organic matter and the formation of THM. Malays. J. Anal. Sci., 13(1), 94–99. Scopus.

Yildiz, Y. S., Koparal, A. S., Irdemez, S., & Keskinler, B. (2007). Electrocoagulation of synthetically prepared waters containing high concentration of NOM using iron cast electrodes. Journal of Hazardous Materials, 139(2), 373–380. Scopus. https://doi.org/10.1016/j.jhazmat.2006.06.044

Yu, W.-Z., Liu, H.-J., Xu, L., Qu, J.-H., & Graham, N. (2013). The pre-treatment of submerged ultrafiltration membrane by coagulation-Effect of polyacrylamide as a coagulant aid. Journal of Membrane Science, 446, 50–58. Scopus. https://doi.org/10.1016/j.memsci.2013.06.012

Zhan, X., Gao, B., Yue, Q., Liu, B., Xu, X., & Li, Q. (2010). Removal natural organic matter by coagulation-adsorption and evaluating the serial effect through a chlorine decay model. Journal of Hazardous Materials, 183(1–3), 279–286. Scopus. https://doi.org/10.1016/j.jhazmat.2010.06.132

Zhao, H., Wang, L., Hanigan, D., Westerhoff, P., & Ni, J. (2016). Novel Ion-Exchange Coagulants Remove More Low Molecular Weight Organics than Traditional Coagulants. Environmental Science and Technology, 50(7), 3897–3904. Scopus. https://doi.org/10.1021/acs.est.6b00635

Zhao, S., Gao, B., Wang, Y., & Yang, Z. (2013). Influence of a new coagulant aid-Enteromorpha extract on coagulation performance and floc characteristics of aluminum sulfate coagulant in kaolin-humic acid solution treatment. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 417, 161–169. Scopus. https://doi.org/10.1016/j.colsurfa.2012.10.062

Zhao, Y., Phuntsho, S., Gao, B., & Shon, H. (2017). Polytitanium sulfate (PTS): Coagulation application and Ti species detection. Journal of Environmental Sciences (China), 52, 250–258. Scopus. https://doi.org/10.1016/j.jes.2016.04.008

Zhao, Y. X., Gao, B. Y., Shon, H. K., Cao, B. C., & Kim, J.-H. (2011). Coagulation characteristics of titanium (Ti) salt coagulant compared with aluminum (Al) and iron (Fe) salts. Journal of Hazardous Materials, 185(2–3), 1536–1542. Scopus. https://doi.org/10.1016/j.jhazmat.2010.10.084

Zhao, Y. X., Gao, B. Y., Shon, H. K., Kim, J.-H., Yue, Q. Y., & Wang, Y. (2011). Floc characteristics of titanium tetrachloride (ticl4) compared with aluminum and iron salts in humic acid-kaolin synthetic water treatment. Separation and Purification Technology, 81(3), 332–338. Scopus. https://doi.org/10.1016/j.seppur.2011.07.041

Zhao, Y. X., Gao, B. Y., Zhang, G. Z., Qi, Q. B., Wang, Y., Phuntsho, S., Kim, J.-H., Shon, H. K., Yue, Q. Y., & Li, Q. (2014). Coagulation and sludge recovery using titanium tetrachloride as coagulant for real water treatment: A comparison against traditional aluminum and iron salts. Separation and Purification Technology, 130, 19–27. Scopus. https://doi.org/10.1016/j.seppur.2014.04.015

Zhao, Y. X., Phuntsho, S., Gao, B. Y., Huang, X., Qi, Q. B., Yue, Q. Y., Wang, Y., Kim, J.-H., & Shon, H. K. (2013). Preparation and characterization of novel polytitanium tetrachloride coagulant for water purification. Environmental Science and Technology, 47(22), 12966–12975. Scopus. https://doi.org/10.1021/es402708v

Zhao, Y. X., Phuntsho, S., Gao, B. Y., Yang, Y. Z., Kim, J.-H., & Shon, H. K. (2015). Comparison of a novel polytitanium chloride coagulant with polyaluminium chloride: Coagulation performance and floc characteristics. Journal of Environmental Management, 147, 194–202. Scopus. https://doi.org/10.1016/j.jenvman.2014.09.023

Zheng, H., Zhu, G., Jiang, S., Tshukudu, T., Xiang, X., Zhang, P., & He, Q. (2011). Investigations of coagulation-flocculation process by performance optimization, model prediction and fractal structure of flocs. Desalination, 269(1–3), 148–156. Scopus. https://doi.org/10.1016/j.desal.2010.10.054

Zhu, G., Zheng, H., Zhang, Z., Tshukudu, T., Zhang, P., & Xiang, X. (2011). Characterization and coagulation-flocculation behavior of polymeric aluminum ferric sulfate (PAFS). Chemical Engineering Journal, 178, 50–59. Scopus. https://doi.org/10.1016/j.cej.2011.10.008

Zietzschmann, F., Worch, E., Altmann, J., Ruhl, A. S., Sperlich, A., Meinel, F., & Jekel, M. (2014). Impact of EfOM size on competition in activated carbon adsorption of organic micro-pollutants from treated wastewater. Water Research, 65, 297–306. Scopus. https://doi.org/10.1016/j.watres.2014.07.043

Zin, N. S. M., Aziz, H. A., Adlan, M. N., Ariffin, A., Yusoff, M. S., & Dahlan, I. (2015). Application of a pre-hydrolyzed iron coagulant on partially stabilized leachate. Desalination and Water Treatment, 54(11), 2951–2958. Scopus. https://doi.org/10.1080/19443994.2014.905973

Zouboulis, A. I., Moussas, P. A., & Vasilakou, F. (2008). Polyferric sulphate: Preparation, characterisation and application in coagulation experiments. Journal of Hazardous Materials, 155(3), 459–468. Scopus. https://doi.org/10.1016/j.jhazmat.2007.11.108