Removal of ciprofloxacin from hospital wastewater using electrocoagulation technique by aluminum electrode: Optimization and modelling through response surface methodology
Graphical abstract
Major pathways of antibiotics release into the environment which cause antibiotic resistance for human.
Introduction
The 1960s was a decade that for the first times the presence of pharmaceuticals and personal care products (PPCPs) were diagnosed in surface waters in United States and Europe. Antibiotics as one of the most widely used PPCPs are approximately 90% excreted in urine and up to 75% in animal excrement, entering to the wastewater system as their parent forms (El-Shafey et al., 2012). Ciprofloxacin (CIP) as a synthetic antibiotic has been widely used for treatment of bacterial infectious disease in humans and animals. It is noteworthy to mention that drug manufacturers and hospitals are the most important sources of contaminated wastewaters. Inappropriate disposal of unused or expired CIP and its incomplete metabolization severely results in its increasing contamination in surface water during the last decade (Dewitte et al., 2008, El-Shafey et al., 2012). According to the statistics presented by the health communities, the amount of CIP contamination discerned in surface water and underground water were within the concentration range of 1˂ μg L−1, respectively. However, the detected amount of CIP in the wastewater of hospitals and drug manufacturers is much higher up to 150 μg L−1 and 50 mg L−1, respectively, which is extremely harmful to the health of the human beings (El-Shafey et al., 2012). Most of the conventional treatments such as activated sludge and trickling filter applied in wastewater treatment plants were unsuccessful which results in releasing them in environment and consequently contamination of surface water, soil and ground water. It is reported that the presence of CIP in daily drinking water may cause nervousness, nausea, vomiting, headaches, diarrhea and tremors. Higher concentrations may cause serious adverse effects including thrombocytopenia, acute renal failure, and elevation of liver enzymes, eosinophilia and leucopenia. On the other hand, the presence of CIP in water sources results in development of bacteria resistant to antibiotics which seriously emerging threat to public health and requires action across all government sectors and societies (Bajpai et al., 2012, Wang et al., 2010, Wu et al., 2010, Zaidi et al., 2016). The treatments of resistant bacteria are difficult, costly and toxic which require alternative medications or higher doses (Somayajula et al., 2012, Vasudevan, 2014, Vasudevan et al., 2011a, Vasudevan et al., 2011b) (Fig. 1).
Literature surveys revealed that developing an efficient and economical procedure for CIP contamination removal from drinking water supply and wastewaters before releasing them into the environment received a great attention, recently. Since CIP is resistant to microbial metabolism, it cannot be efficiently degraded by means of biological treatment processes (Palmisano et al., 2015). Several techniques such as adsorption (Gandhi et al., 2016, Kamaraj et al., 2015, Kamaraj et al., 2014a, Kamaraj et al., 2014b, Kamaraj et al., 2017, Kamaraj and Vasudevan, 2016), advanced oxidation process (Dewitte et al., 2008), have been studied for removal of CIP from the contaminated water. However, among all of them electrochemical techniques such as electrocoagulation (EC) as an advanced, efficient and economical technique received extensive practical applicability by providing satisfactory result for treating various wastewater contaminants such as heavy metals (Kamaraj and Vasudevan, 2015), fluoride (Emamjomeh and Sivakumar, 2009), dyes (Daneshvar et al., 2006), drug (Khandegar and Saroha, 2013a), phenol (Vasudevan, 2014). EC technique included coagulation process in which coagulant agent gets produced in situ through electrochemical reactions of sacrificial anode dissolution (Khandegar and Saroha, 2013b). Electro-synthesized of coagulant provide competitive advantages of producing less sludge thus lowering the sludge disposal cost, removing many species that chemical coagulation cannot remove and the produced sludge is more readily filterable and can be utilized as a soil additive. Other considerable advantages of EC technique including low cost process and maintenance, no harmful substances generation, producing low amount of TDS and secondary pollutants and removing the smallest size of colloidal particles caused its increasingly usage. However, it does not require any chemical storage like adsorption or biological processes. Besides the current studies using electrochemistry, on the other hand, using electrochemical sensors as a device which provides a certain type of response that is directly related to the quantity of a chemical species such as contaminants, showed a rapid growing scientific studies in environmental monitoring field and practiced by the current research group recently (Ahmadzadeh et al., 2015a, Ahmadzadeh et al., 2015c, Fouladgar and Ahmadzadeh, 2016, Kassim et al., 2011, Pardakhty et al., 2016, Rezayi et al., 2014, Soltani et al., 2016).
To the best of our knowledge, there is not any report on CIP removal using EC process by aluminum electrodes. So far only one report based on EC process was found for CIP removal from aqueous solution using iron electrode (Barışçı and Turkay, 2016). However, the reported EC process suffered from low removal efficiency for CIP contaminants in its optimized concentration of 5 mg L−1 in compare to the current work with optimized concentration of 32.5 mg L−1 CIP contaminants. Hence developing of EC process using aluminum electrodes can be regarded as a new and potential research area for CIP contamination removal from hospital and industrial wastewater. Since, most of the reported studies are based on one factor at the time method, in the current study, RSM was used to evaluate the main effects of parameters, their simultaneous interactions and quadratic effect to achieve the optimum condition for EC process. The effects of various operating parameters such as electrolyte type and concentration, inter-electrode distance, initial CIP concentration, pH, current density and reaction time were investigated to achieve the best efficient and CIP contamination remove condition.
Section snippets
Chemicals
CIP (C17H18FN3O3·HCl·H2O, 385.8 mol wt.) purchased from Darou Pakhsh Pharmaceutical Company, Mashhad, Iran. The mobile phase was prepared using HPLC grade acetonitrile and analytical grade hydrochloric acid. Electrolytes including MgSO4, NaCl, KNO3, Na2SO4, and CaCl2 were purchased from Merck Company. Hydrochloric acid and sodium hydroxide from Sigma-Aldrich were used for pH adjustments. Acetic acid and ethanol were obtained from Merck Company. All reagents used are analytical reagent grade with
Preliminary evaluation of electrocoagulation process
The effect of electrolyte type and concentration on the removal efficiency of CIP were investigated. The maximum removal was obtained using NaCl as electrolyte at equilibrium time of 20 min (see Fig. 2). Literature surveys revealed that addition of appropriate electrolyte significantly improved the efficiency of EC process due to increasing the conductivity of the wastewater which affects the Faradic yield, cell voltage and consequently energy consumption of the process.
The presence of NaCl
Conclusions
The current work was aimed to investigate the effect of independent variables on the removal efficiency of CIP from hospital wastewater using response surface methodology. The experimental obtained results revealed that under optimal condition of pH 7.78, inter-electrode distance 1 cm, reaction time 20 min, current density 12.5 mA cm−2 and electrolyte dose of 0.07 M NaCl with the initial CIP concentration of 32.5 mg L−1, the CIP removal efficiency of 88.57% was achieved which is in satisfactory
Acknowledgments
The authors express their appreciation to Neuroscience Research Center and Pharmaceutics Research Center both affiliated to Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.
References (43)
- et al.
A conductometric study of complexation reaction between meso-octamethylcalix [4] pyrrole with titanium cation in acetonitrile-ethanol binary mixtures
Int. J. Electrochem. Sci
(2011) - et al.
Highly selective detection of titanium(III) in industrial waste water samples using meso-octamethylcalix [4] pyrrole-doped PVC membrane ion-selective electrode
Electrochim. Acta
(2015) - et al.
Conductometric measurements of complexation study between 4-isopropylcalix [4] arene and Cr3+ cation in THF-DMSO binary solvents
Measurement
(2015) - et al.
Integrated ozone—electrocoagulation process for the removal of pollutant from industrial effluent: optimization through response surface methodology
Chem. Eng. Process.: Process Intensif.
(2016) - et al.
Ozone assisted electrocoagulation for the treatment of distillery effluent
Desalination
(2012) - et al.
Combination of electrocoagulation with advanced oxidation processes for the treatment of distillery industrial effluent
Process Saf. Environ. Prot.
(2016) - et al.
Decolorization of basic dye solutions by electrocoagulation: an investigation of the effect of operational parameters
J. Hazard. Mater.
(2006) - et al.
Ciprofloxacin adsorption from aqueous solution onto chemically prepared carbon from date palm leaflets
J. Environ. Sci.
(2012) - et al.
Fluoride removal by a continuous flow electrocoagulation reactor
J. Environ. Manag.
(2009) - et al.
Boron removal from produced water using electrocoagulation
Process Saf. Environ. Prot.
(2014)
Application of a nanostructured sensor based on NiO nanoparticles modified carbon paste electrode for determination of methyldopa in the presence of folic acid
Appl. Surf. Sci.
Adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) from water by in situ generated metal hydroxides using sacrificial anodes
J. Taiwan Inst. Chem. Eng.
An in situ electrosynthesis of metal hydroxides and their application for adsorption of 4-chloro-2-methylphenoxyacetic acid (MCPA) from aqueous solution
J. Environ. Chem. Eng.
Kinetics, thermodynamics and isotherm modeling for removal of nitrate from liquids by facile one-pot electrosynthesized nano zinc hydroxide
J. Mol. Liq.
Evaluation of electrocoagulation process for the removal of strontium and cesium from aqueous solution
Chem. Eng. Res. Des.
Electrocoagulation for the treatment of textile industry effluent—a review
J. Environ. Manag.
Electrocoagulation for the treatment of textile industry effluent—a review
J. Environ. Manag.
Synthesis of CuO nanoparticles through green route using Citrus limon juice and its application as nanosorbent for Cr(VI) remediation: process optimization with RSM and ANN-GA based model
Process Saf. Environ. Prot.
Highly sensitive and efficient voltammetric determination of ascorbic acid in food and pharmaceutical samples from aqueous solutions based on nanostructure carbon paste electrode as a sensor
J. Mol. Liq.
Determination of hydroquinone in food and pharmaceutical samples using a voltammetric based sensor employing NiO nanoparticle and ionic liquids
J. Mol. Liq.
Sonoelectrochemical oxidation for decolorization of Reactive Red 195
Ultrason. Sonochem.
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