Removal of bacteriophage f2 in water by nanoscale zero-valent iron and parameters optimization using response surface methodology
Introduction
As the population has increased dramatically and the urbanization has been accelerated, water shortage is increasingly intensified. In order to solve the shortage of water resources, wastewater reclamation and reuse seems to be an effective way [1], [2]. However, lots of issues pose significant risks to human health in the process of wastewater reuse, such as interferon, hormone, suspended solids, heavy metals and microbiological load, especially pathogenic enteric viruses [3], [4]. It is presumed that viruses are responsible for waterborne diseases [5], [6]. In the US, a few outbreaks of waterborne diseases were attributed to viruses which are more difficult to be analyzed than bacterial pathogens [7]. Every year approximately 600,000 children worldwide die from Rotavirus infection [8]. Virus removal has become an essential problem to be solved in water use.
Traditional chlorination, as a dominant disinfection method, would produce disinfection by-products (DBPs), such as trihalomethanes, haloacetic acids and haloacetonitriles [9]. Although UV disinfection can inactivate some virus without forming DBPs [10], it requires significant energy and sometimes photoreactivation phenomenon would occur [11], [12]. Microfiltration is highly effective for controlling pathogenic bacteria and protozoa; however, the outcome turns to be reverse for viruses because their sizes are far smaller than those of membrane [13], [14], [15]. What’s more, the cost and fouling of membrane is a severe issue that may limit its application to some extent [16].
For the past decades, zero-valent iron (ZVI) has been applied in permeable reactive barriers (PRBs) for groundwater remediation [17]. And some studies showed that commercial iron granules could inactivate and remove virus [18], [19]. However, surface passivation of iron is one of the major problems, which seriously affects the activity of zero-valent iron and its working life [20], [21].
Owing to its small size, high specific surface and surface activity [22], nanoscale zero-valent iron (NZVI) was studied in removing bacteria and viruses, e.g., Escherichiacoli, Ad41, MS2 and ΦX174 from drinking water [23], [24]. However, the study of NZVI in removing phage f2 under different conditions was rather limited. And to our best knowledge, multiple factor experiment which could examine the effect of multiple factors on the process has not yet been studied or reported. Bacteriophage f2 is a non-enveloped virus with a single-stranded RNA genome. Its structural properties such as the property of nucleic acid, particle size, surface shape, and stability to pH value are very close to those of enteric viruses, especially HAV and poliovirus. The amount of colibacteriophage in natural environment is close to that of enteric viruses, and the seasonal variation, survival ability, resistance to disinfectants, behavior in water are also similar. Moreover, bacteriophage f2 infects bacteria only, and is harmless to human and other living beings. So bacteriophage f2 was selected as a model virus in this study to examine the removal of virus by NZVI. Usually, the effect of experimental parameters was studied with single factor experiments. In fact, more than two parameters would influence the reaction process, and the interactions between the parameters are significant in statistics. So the multiple factor experiment is needed to study the main effect of the parameters and the interactions.
In this study, a series of single factor experiments were performed to examine the ability of NZVI to remove bacteriophage f2 in water. And the effects of NZVI dose, virus concentration, pH value, and rotation rate on the removal rate of virus were studied. In addition, response surface methodology (RSM), one of the multiple factor experiment methods, was applied to optimizing the experimental variables for virus inactivation by employing a three-level, four-variable Box–Behnken design (BBD).
Section snippets
Chemicals
The chemicals used were: sodium borohydride, ferrous sulfate, hydrochloric acid, sodium hydroxide, nutrient agar medium, nutrient broth, and agar. All chemicals were of reagent grade and used without further purification. All chemicals were purchased from the Sinopharm Chemical Reagent Beijing (Beijing, China). And all solutions were prepared with ultrapure water from a MΩ Milli Q system (Millipore, US).
Preparation and characterization of NZVI
NZVI particles were synthesized by aqueous-phase reduction of ferrous sulfate with sodium
Comparison between NZVI and ZVI on bacteriophage f2 removal
The removal of bacteriophage f2 by NZVI and ZVI under the same conditions was shown in Fig. 1. The dose of NZVI and ZVI were both 100 mg L−1. The results were expressed as −log (N/N0), where N and N0 were residual and initial concentration of viable viruses (PFU/mL), respectively. And a control test suggested that the concentration of virus did not change without iron.
As shown in Fig. 1, approximately 5.1 log of bacteriophage f2 was removed by NZVI within 30 min; while less than 0.5 log of
Conclusions
Nanoscale zero-valent iron particles showed a brilliant ability in terms of removing bacteriophage f2 and were definitely more efficient than commercial iron particles.
A series of single factor experiments were carried out to examine the effect of various parameters on the removal rate of bacteriophage f2. The removal rate was increased with the increase of NZVI dose and rotation rate, but decreased with the increase of pH value and virus concentration. The removal process involved reversible
Acknowledgements
This work was supported by the National Natural Science Foundation (Grant No. 51108454), the Fundamental Research Funds for the Central Universities, and the Research Funds of Renmin University of China (Grant No. 11XNK016), which are greatly acknowledged.
References (44)
Chlorination disinfection by-products, public health risk trade-offs and me
Water Res.
(2009)- et al.
Advanced treatment for municipal wastewater reuse in agriculture. UV disinfection: parasite removal and by-product formation
Desalination
(2003) - et al.
Photoreactivation of Legionella pneumophila after inactivation by low-or medium-pressure ultraviolet lamp
Water Res.
(2004) - et al.
Virus removal from water and wastewater using membranes
J. Membr. Sci.
(1995) - et al.
Performance evaluation of a permeable reactive barrier for remediation of dissolved chlorinated solvents in groundwater
J. Hazard. Mater.
(1999) - et al.
Predicting longevity of iron permeable reactive barriers using multiple iron deactivation models
J. Contam. Hydrol.
(2012) - et al.
Comparison of reductive dechlorination of p-chlorophenol using Fe0 and nanosized Fe0
J. Hazard. Mater.
(2007) - et al.
Removal of viruses and bacteriophages from drinking water using zero-valent iron
Sep. Purif. Technol.
(2012) - et al.
Optimization for decolorization of azo dye acid green by 20 ultrasound and H2O2 using response surface methodology
J. Hazard. Mater.
(2009) - et al.
Response surface methodology (RSM) as a tool for optimization in analytical chemistry
Talanta
(2008)
Virus removal by iron coagulation microfiltration
Water Res.
Inactivation of MS2 coliphage by Fenton’s reagent
Water Res.
The Fenton reagents
Free Radical Biol. Med.
Oxygen reduction on iron. Part III. An analysis of the rotating disk-ring electrode measurements in near neutral solutions
J. Electroanal. Chem.
Oxygen reduction on iron. Part IV. The reduction of hydrogen peroxide as the intermediate in oxygen reduction reaction in alkaline solutions
Electrochim. Acta
On the mechanism of microbe inactivation by metallic iron
J. Hazard. Mater.
An analysis of the evolution of reactive species in Fe0/H2O system
J. Hazard. Mater.
Optimizing aerobic biodegradation of dichloromethane using response surface methodology
J. Environ. Sci.
Water reuse in Japan
Water. Sci. Technol.
Water from (waste) water—the dependable water resource
Water. Sci. Technol.
Virus persistence in groundwater
Appl. Environ. Microbial.
Occurrence of viruses in US groundwaters
J. Am. Water. Works. Assoc.
Cited by (33)
Application of response surface methodology for hazard analysis of 2-butanol oxidation to 2-butanone using RC1 calorimetry
2022, Journal of Loss Prevention in the Process IndustriesCitation Excerpt :In order to identify the interactions between these parameters on the output variable (heat release), response surface methodology (RSM) was used. The purpose of RSM is to optimize a response of interest which is influenced by several variables (Ahmad et al., 2011; Cheng et al., 2014; Danmaliki et al., 2017; Liu et al., 2015; Montgomery, 2012; Xu et al., 2015; Zhang and Pan, 2014; Zheng et al., 2011, 2015). This is described in detail in Section 3.
Electrochemical membrane technology for disinfection
2022, Electrochemical Membrane Technology for Water and Wastewater TreatmentProcess optimisation through Response Surface Methodology for treatment of acid mine drainage using carbon nanotubes-infused thin film nanocomposite membranes
2021, Physics and Chemistry of the EarthCitation Excerpt :This method had the best fit of data obtained from experimental design for determining the main and mutual effects between the effective parameters and used for developing, improving and optimising the process (Danmaliki et al., 2017; Safari et al., 2019). The main purpose of RSM is to determine the operational condition of the response that is affected by various factors of the process (Cheng et al., 2014). This method is widely used in Chemical engineering particularly to optimise membrane-based processes (Fan et al., 2019; Safari et al., 2019).