Virus removal by an in-line coagulation–ceramic microfiltration process with high-basicity polyaluminum coagulation pretreatment

The ability of in-line coagulation pretreatment with high-basicity polyaluminum chloride (PACl) coagulants to enhance virus removal by ceramic microfiltration (MF) was examined by comparing virus removal efficiencies from water pretreated with PACl-2.2 (basicity 2.2) and PACl-2.5 (basicity 2.5) versus alum, a synthetic aluminum chloride (AlCl3) solution, and two commercially available PACls, PACl-1.5 and PACl-1.8. The virus removal ratios for AlCl3, alum, PACl-1.5, and PACl-1.8 decreased markedly when the pH of the treated water shifted from 6.8 to 7.8, but was high at both pHs for PACl-2.2 and PACl-2.5. PACl-2.5 contains Al13 species and possibly Al30 species, and has a high colloid charge density. It removed viruses more efficiently than the other aluminum-based coagulants, not only at neutral pH, but also under weakly alkaline conditions. Moreover, the in-line coagulation–ceramic MF process with PACl-2.5 pretreatment removed not only viruses but also dissolved organic carbon and UV260-absorbing natural organic matter more efficiently and resulted in a lower residual aluminum concentration than did commercially available PACls, especially under weakly alkaline conditions. A combination of coagulation pretreatment with a high-basicity PACl and ceramic MF can provide effective treatment of drinking water over a broader pH range than is possible with commercially available aluminum-based coagulants.

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Adsorption of strontium on different sodium-enriched bentonites

Journal of the Serbian Chemical Society ◽

10.2298/jsc161010008m ◽

2017 ◽

Vol 82 (4) ◽

pp. 449-463 ◽

Cited By ~ 6

Author(s):

Sanja Marinovic ◽

Marija Ajdukovic ◽

Natasa Jovic-Jovicic ◽

Tihana Mudrinic ◽

Bojana Nedic-Vasiljevic ◽

...

Keyword(s):

Cation Exchange ◽

Adsorption Capacity ◽

Textural Properties ◽

X Ray Diffraction ◽

Order Model ◽

Surface Areas ◽

Alkaline Conditions ◽

Langmuir Isotherm Model ◽

Pseudo Second Order ◽

Ph Range

Bentonites from three different deposits (Wyoming, TX, USA and Bogovina, Serbia) with similar cation exchange capacities were sodium enriched and tested as adsorbents for Sr2+ in aqueous solutions. X-Ray diffraction analysis confirmed successful Na-exchange. The textural properties of the bentonite samples were determined using low-temperature the nitrogen physisorption method. Significant differences in the textural properties between the different sodium enriched bentonites were found. Adsorption was investigated with respect to adsorbent dosage, pH, contact time and the initial concentration of Sr2+. The adsorption capacity increased with pH. In the pH range from 4.0?8.5, the amount of adsorbed Sr2+ was almost constant but 2?3 times smaller than at pH ?11. Further experiments were performed at the unadjusted pH since extreme alkaline conditions are environmentally hostile and inapplicable in real systems. The adsorption capacity of all the investigated adsorbents toward Sr2+ was similar under the investigated conditions, regardless of significant differences in the specific surface areas. It was shown and confirmed by the Dubinin?Radushkevich model that the cation exchange mechanism was the dominant mechanism of Sr2+ adsorption. Their developed microporous structures contributed to the Sr2+ adsorption process. The adsorption kinetics obeyed the pseudo-second-order model. The isotherm data were best fitted with the Langmuir isotherm model.

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Flotation Behavior of Diatomite and Albite Using Dodecylamine as a Collector

Minerals ◽

10.3390/min8090371 ◽

2018 ◽

Vol 8 (9) ◽

pp. 371 ◽

Cited By ~ 1

Author(s):

Ying Gao ◽

Yuexin Han ◽

Wenbo Li

Keyword(s):

Unit Area ◽

Alkaline Ph ◽

Force Microscopy ◽

Atomic Force ◽

Mineral Flotation ◽

Alkaline Conditions ◽

Negative Surface ◽

Negative Surface Charge ◽

Ph Range ◽

First Time

The flotation behaviors of diatomite and albite using dodecylamine (DDA) as a collector were investigated and compared. The pure mineral flotation results indicate that the flotability difference between albite and diatomite is above 87% at pH 5.5 to 10.5. The recovery of albite improves with increasing DDA dosage at pH 5.5 to 10.5. In the same pH range, diatomite has weaker flotability than albite, particularly in alkaline pH pulp. Zeta potential measurements indicate that diatomite has a higher negative surface charge than albite at pH 7 to 12, DDA interacts strongly with albite and weakly with diatomite. Thus, DDA preferentially absorbs on albite surface rather than diatomite under alkaline conditions. Fourier transform infrared spectra (FTIR) indicate that the amount of DDA adsorbed to albite is greater than that adsorbed to diatomite, under the same conditions. The adsorption of DDA on the surface of diatomite is investigated by using atomic force microscopy (AFM) for the first time. The adsorption of the collector DDA on the surface of albite per unit area is greater than that on diatomite. This accounts for the lower recovery of diatomite than that of albite.

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Application of Composite Pre-Polymerized Coagulants for the Treatment of High-Strength Industrial Wastewaters

Water ◽

10.3390/w12051258 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1258 ◽

Cited By ~ 1

Author(s):

Athanasia K. Tolkou ◽

Anastasios I. Zouboulis

Keyword(s):

High Strength ◽

Aluminum Concentration ◽

The Novel ◽

Industrial Wastewaters ◽

Residual Aluminum ◽

Yeast Production ◽

Wastewater Samples ◽

Composite Coagulant ◽

Inorganic Composite

The aim of this study was the investigation of alternative pre-polymerized coagulants for the treatment of high-strength industrial wastewaters, such as those created by tanneries, or by yeast production industries. The novel inorganic composite coagulant examined in this study (as well as variations of it) was denoted as PSiFAC1.5-10-15. The contribution of a typical polyelectrolyte to improve the effectiveness of the coagulation/flocculation (C/F) process was additionally studied, either by adding it separately (i.e., as a flocculant aid) or by co-polymerizing it within the structure of inorganic coagulant (denoted as PAPEFAC1.5-10-15). It was found that the PSiFAC1.5:10:15 coagulant, either with or without the addition of polyelectrolyte, can provide better efficiency for the C/F process than the conventional coagulants. For example, the addition of 80 mg Al/L in yeast production wastewater samples resulted in a 56% reduction of COD, 40% of turbidity, and 43% of phosphates, regarding the pre-treated anaerobically wastewater samples and reduced by an extra 22%, 14%, and 38% for the pre-treated anaerobically plus aerobically wastewater samples, respectively. The residual aluminum concentration in the treated wastewaters was found to be below the legislation limit of 200 μg Al/L. The characterization of coagulants showed the relatively higher Al13 content of 51% and 43% for the cases of PSiFAC1.5-10-15 and PAPEFAC1.5-10-15, respectively, accompanied by the high zeta-potential measurements (50.5 and 39.5 mV).

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Fate and fractionation of aluminum in a full-scale Al-based drinking water treatment plant

Journal of Water Supply Research and Technology—AQUA ◽

10.2166/aqua.2020.005 ◽

2020 ◽

Vol 69 (5) ◽

pp. 469-477

Author(s):

Hongyuan Liu ◽

Haoran Liu ◽

Yawei Xie

Keyword(s):

Drinking Water ◽

Treatment Plant ◽

Drinking Water Treatment ◽

Water Treatment Plant ◽

Aluminum Concentration ◽

Average Water Temperature ◽

Treated Water ◽

Residual Aluminum ◽

Average Water ◽

Particle Counts

Abstract Residual aluminum in drinking water is widely concerning due to its potentially harmful effect on human health and drinking water distribution systems. The fate and fractionation of aluminum and the factors influencing residual aluminum in a full-scale Al-based drinking water treatment plant (DWTP) was presented in Jiaxing, China. The results showed that treated water residual aluminum concentration was less than 0.1 mg/L regardless of the seasonal change of raw water aluminum concentration. The addition of secondary flocculation had a negligible influence on treated water residual aluminum concentration due to the efficient removal of particulate aluminum by sand filter. Residual aluminum concentration of treated water was lower (mean 0.037 mg/L) in summer (average water temperature was 29 °C) than that (mean 0.067 mg/L) in winter (average water temperature was 16 °C). Significant positive relationships between particulate aluminum concentration and particle counts, as well as the total aluminum concentration of treated water and turbidity, were found. Those relationships provided the possibility to estimate residual aluminum concentration by monitoring particle counts and turbidity.

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Enhanced virus filtration in hybrid membranes with MWCNT nanocomposite

Royal Society Open Science ◽

10.1098/rsos.181294 ◽

2019 ◽

Vol 6 (1) ◽

pp. 181294 ◽

Cited By ~ 7

Author(s):

Zoltán Németh ◽

Gergő Péter Szekeres ◽

Mateusz Schabikowski ◽

Krisztina Schrantz ◽

Jacqueline Traber ◽

...

Keyword(s):

Electron Microscopy ◽

Drinking Water ◽

Electrostatic Interactions ◽

Membrane Separation ◽

Area Measurement ◽

Hybrid Membranes ◽

Potential Measurement ◽

Virus Removal ◽

Multi Walled Carbon Nanotubes ◽

Ph Range

Membrane separation is proved to be a powerful tool for several applications such as wastewater treatment or the elimination of various microorganisms from drinking water. In this study, the efficiency of inorganic composite-based multi-walled carbon nanotube (MWCNT) hybrid membranes was investigated in the removal of MS2 bacteriophages from contaminated water. With this object, multi-walled carbon nanotubes were coated with copper(I) oxide, titanium(IV) oxide and iron(III) oxide nanoparticles, respectively, and their virus removal capability was tested in both batch and flow experiments. Considering the possible pH range of drinking water, the filtration tests were carried out at pH 5.0, 7.5 and 9.0 as well. The extent of MS2 removal strongly depended on the pH values for each composite, which can be due to electrostatic interactions between the membrane and the virus. The most efficient removal (greater than or equal to 99.99%) was obtained with the Cu 2 O-coated MWCNT membrane in the whole pH range. The fabricated nanocomposites were characterized by X-ray diffraction, specific surface area measurement, dynamic light scattering, zeta potential measurement, Raman spectroscopy, transmission electron microscopy and scanning electron microscopy. This study presents a simple route to design novel and effective nanocomposite-based hybrid membranes for virus removal.

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Complexation of Th(IV) and Eu(III) by α-isosaccharinic acid under alkaline conditions

Radiochimica Acta ◽

10.1524/ract.2001.89.6.393 ◽

2001 ◽

Vol 89 (6) ◽

Cited By ~ 45

Author(s):

K. Vercammen ◽

M.A. Glaus ◽

Luc R. Van Loon

Keyword(s):

Stability Constants ◽

Data Sets ◽

Complexation Reaction ◽

Sorption Data ◽

Alkaline Conditions ◽

The Stability ◽

Ph Range ◽

Complexation Reactions ◽

Best Fit ◽

Isosaccharinic Acid

The complexation of Th(IV) and Eu(III) by α-isosaccharinic acid (ISA) has been studied in the pH range from 10.7 to 13.3 by batch sorption experiments, and the influence of Ca on the complexation was investigated. Sixteen data sets – each determined at variable ISA concentrations – are used to determine the stoichiometry of the complexation reactions and the stability constants. Based on best-fit analysis of the sorption data, it is postulated that 1:1 Th:ISA complexes are formed in the absence of Ca according to the complexation reaction: Th+ISA↔(ThISA)

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Purification and characterization of Al13 species in coagulant polyaluminum chloride

Journal of Environmental Sciences ◽

10.1016/s1001-0742(09)60005-x ◽

2009 ◽

Vol 21 (1) ◽

pp. 18-22 ◽

Cited By ~ 17

Author(s):

Baoyu GAO ◽

Yongbao CHU ◽

Qinyan YUE ◽

Yan WANG

Keyword(s):

Purification And Characterization ◽

Polyaluminum Chloride ◽

Al13 Species

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Fe3O4nanoparticles coated with a guanidinium-functionalized polyelectrolyte extend the pH range for phosphate binding

Journal of Materials Chemistry A ◽

10.1039/c7ta04054g ◽

2017 ◽

Vol 5 (35) ◽

pp. 18476-18485 ◽

Cited By ~ 15

Author(s):

Laura Paltrinieri ◽

Min Wang ◽

Sumit Sachdeva ◽

Nicolaas A. M. Besseling ◽

Ernst J. R. Sudhölter ◽

...

Keyword(s):

Phosphate Adsorption ◽

Functional Coatings ◽

Phosphate Binding ◽

Alkaline Conditions ◽

Ph Range

This work shows the enhanced effect of functional coatings on phosphate adsorption at alkaline conditions using Fe3O4NPs.

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Factors affecting germination of horseweed (Conyza canadensis)

Weed Science ◽

10.1614/ws-06-006r2.1 ◽

2006 ◽

Vol 54 (5) ◽

pp. 898-902 ◽

Cited By ~ 104

Author(s):

Vijay K. Nandula ◽

Thomas W. Eubank ◽

Daniel H. Poston ◽

Clifford H. Koger ◽

Krishna N. Reddy

Keyword(s):

Seedling Emergence ◽

Soil Surface ◽

Conyza Canadensis ◽

Light Conditions ◽

Complete Darkness ◽

Continuous Darkness ◽

Factors Affecting ◽

Nacl Concentration ◽

Alkaline Conditions ◽

Ph Range

The influence of environmental factors on germination and emergence of horseweed was examined in growth chamber experiments. Germination was highest (61%) under 24/20 C day/night temperature under light. Horseweed seed germination was observed under both light (13 h photoperiod) and complete darkness (24 h), but germination under continuous darkness was only 0 to 15% compared with 0 to 61% under light. All other experiments were conducted under 24/20 C and 13-h light conditions. Germination was 19 to 36% over a pH range from 4 to 10, with a trend toward higher germination under neutral-to-alkaline conditions. Horseweed germination was > 20% at < 40 mM NaCl concentration and lowest (4%) at 160 mM NaCl. These data suggest that even at high soil salinity conditions, horseweed can germinate. Germination of horseweed decreased from 25% to 2% as osmotic potential increased from 0 (distilled water) to −0.8 MPa, indicating that germination can still occur under moderate water stress conditions. Horseweed seedling emergence was at its maximum on the soil surface, and no seedlings emerged from seeds placed at a depth of 0.5 cm or higher.

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