Climate change has been described to raise outbreaks of water-born infectious diseases and increases public health concerns. This study aimed at finding out these impacts on cholera infections by ...using Artificial Neural Networks (ANNs) from 2021 to 2050. Daily data for cholera infection cases in Qom city, which is located in the center of Iran, were analyzed from 1998 to 2016. To determine the best lag time and combination of inputs, Gamma Test (GT) was applied. General circulation model outputs were utilized to project future climate pattern under two scenarios of Representative Concentration Pathway (RCP2.6 and RCP8.5). Statistical downscaling was done to produce high-resolution synthetic time series weather dataset. ANNs were applied for simulating the impact of climate change on cholera. The observed climate variables including maximum and minimum temperatures and precipitation were tagged as predictors in ANNs. Cholera cases were considered as the target outcome variable. Projected future (2020-2050) climate in previous step was carried out to assess future cholera incidence. A seasonal trend in cholera infection was seen. Our results elucidated that the best lag time was 21 days. According to the results of downscaling tool, future climate in the study area by 2050 will be warmer and wetter. Simulation of cholera cases indicated that there is a clear trend of increasing cholera cases under the worst scenario (RCP8.5) by the year 2050 and the highest cholera cases observe in warmer months. The precipitation was recognized as the most effective input variable by sensitivity analysis. We observed a significant correlation between low precipitation and cholera infection. There is a strong evidence to show that cholera disease is correlated with environment variables, as low precipitation and high temperatures in warmer months could provide the swifter bacterial replication. These conditions in Iran, especially in the central parts, may raise the cholera infection rates. Furthermore, ANNs is an executive tool to simulate the impact of climate change on cholera to estimate the future trend of cholera incidence for adopting protective measures in endemic areas.
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•g-C3N4/Fe3O4/Ag photocatalyst was successfully synthesized.•A complete removal efficiency of diazinon was accomplished.•Hydroxyl radicals (OH˚) highly facilitated the photocatalytic ...removal of diazinon.
Herein, a well-known pesticide named diazinon was successfully removed from aqueous solutions by the UV photocatalytic process in which g-C3N4/Fe3O4/Ag was applied as a nanocomposite. Initially, g-C3N4/Fe3O4/Ag nanocomposite was synthesized by a hydrothermal method and XRD, FT-IR, SEM, EDX and PL analyses were employed to identify the nanocomposite structure. The best conditions for the complete removal of diazinon (DZN) (i.e., 100 %) were obtained after 60 min under the following conditions: pH = 7, catalyst dosage of 0.5 g/L and DZN concentration of 5 mg/L. The removal reaction followed the first order kinetic model (k, 0.067; R2, 0.9982). Furthermore, the effects of several scavengers such as ammonium oxalate (AO), tert-butanol (TB) and benzoquinone (BQ) on the performance of the removal reaction were investigated revealing that the hydroxyl ions played an active role in the reaction. Finally, the photocatalytic process using the nanocomposite g-C3N4/Fe3O4/Ag proved to be promising for the removal of DZN pesticide from aqueous media.
Abstract
Antibiotics are resistant compounds with low biological degradation that generally cannot be removed by conventional wastewater treatment processes. The use of yolk-shell nanostructures in ...spinning disc photocatalytic reactor (SDPR) enhances the removal efficiency due to their high surface-to-volume ratio and increased interaction between catalyst particles and reactants. The purpose of this study is to investigate the SDPR equipped to Fe
3
O
4
@void@CuO/ZnO yolk-shell thin film nanostructure (FCZ YS) in the presence of visible light illumination in the photocatalytic degradation of amoxicillin (AMX) from aqueous solutions. Stober, co-precipitation, and self-transformation methods were used for the synthesis of FCZ YS thin film nanostructure and the physical and chemical characteristics of the catalyst were analyzed by XRD, VSM,, EDX, FESEM, TEM, AFM, BET, contact angle (CA), and DRS. Then, the effect of different parameters including pH (3–11), initial concentration of AMX (10–50 mg/L), flow rate (10–25 mL/s) and rotational speed (100–400 rpm) at different times in the photocatalytic degradation of AMX were studied. The obtained results indicated that the highest degradation efficiency of 97.6% and constant reaction rate of AMX were obtained under LED visible light illumination and optimal conditions of pH = 5, initial AMX concentration of 30 mg/L, solution flow rate of 15 mL/s, rotational speed of 300 rpm and illumination time of 80 min. The durability and reusability of the nanostructure were tested, that after 5 runs had a suitable degradation rate. Considering the appropriate efficiency of amoxicillin degradation by FCZ YS nanostructure, the use of Fe
3
O
4
@void@CuO/ZnO thin film in SDPR is suggested in water and wastewater treatment processes.
The present study aimed to model and optimize the dimethyl phthalate (DMP) degradation from aqueous solution using UV
C
/ Na
2
S
2
O
8
/Fe
2+
system based on the response surface methodology (RSM). A ...high removal efficiency (97%) and TOC reduction (64.2%) were obtained under optimum conditions i.e. contact time = 90 min, SPS concentration = 0.601 mM/L, Fe
2+
= 0.075 mM/L, pH = 11 and DMP concentration = 5 mg/L. Quenching experiments confirmed that sulfate radicals were predominant radical species for DMP degradation. The effect of CO
3
−
on DMP degradation was more complicated than other aquatic background anions. The possible pathway for DMP decomposition was proposed according to HPLC and GC–MS analysis. The average oxidation state (AOS) and carbon oxidation state (COS) values as biodegradability indicators demonstrated that the UV
C
/SPS/Fe
2+
system can improve the bioavailability of DMP over the time. Finally, the performance of UV
C
/SPS/Fe
2+
system for DMP treatment in different aquatic solutions: tap water, surface runoff, treated and raw wastewater were found to be 95.7, 88.5, 80.5, and 56.4%, respectively.
Graphical abstract
Ciprofloxacin (CIP) is one of the most important antibiotics in pharmaceutical companies’ industrial drains and causes environmental pollution. In this work, a new photocatalyst based on g-C3N4/N, P ...CQD/ZIF-67 was synthesized for CIP photocatalytic degradation. The synthesized sample was characterized by field emission scanning electron microscopy, Fourier transform infrared spectrometer, and X-ray powder diffraction. Synthesized photocatalytic can degrade CIP as 98%. This degradation occurred in 90 mins. The results showed OH° and °O2− radicals have an important role in CIP degradation in pH = 6. Moreover, the bandgap evaluated for g-C3N4/N, P-CQD/ZIF-67 nanocomposite (1.3 eV) is less than g-C3N4 and g-C3N4/N,P CQD, which indicates the faster movement of electrons in the synthesized nanocomposite, so g-C3N4/N,P CQD/ZIF-67 nanocomposite has good application in CIP degradation. The products of CIP degradation were analyzed by LC/MS-MS.
Millions of tons of plastic are consumed annually in the world due to its significant characteristics such as durability, flexibility, and low weight. High consumption has made plastic one of the ...most important municipal solid waste compounds, the quantity of which has increased in recent decades. Plastic solid wastes are known as a threat to the environment, and its efficient management in various aspects such as cost–benefit requires decision-making tools. This study was assessing the cost–benefit of plastic solid waste management by development of an economic model, and definition of different scenarios to change plastic solid waste management status. The results showed that 8971 tons of plastic solid waste were generated annually in the studied city. The plastic solid wastes were finally transferred to either recycling or landfilling site through 5 identified routes. 83 percent of the total recycled plastic solid waste was due to post-separation routes, and only 7.7 percent of the total plastic solid waste was recycled from the source separation route. The economic comparison of scenarios showed that with the aggregation of post-separation routes, the net revenue of plastic solid waste management increases by 334,000 euro per year while increasing the public participation and the ratio of source separation route raises net revenue by 875,000 euro per year, which was the best economic condition among the scenarios. Using life cycle cost method and it’s respected developed economic model truly satisfied the conditions of both, the current plastic solid waste management and the alternative scenarios, and hence can be adopted as a tool for decision-making.
Conventional wastewater treatment processes are often unable to remove antibiotics with resistant compounds and low biological degradation. The need for advanced and sustainable technologies to ...remove antibiotics from water sources seems essential. In this regard, the effectiveness of a spinning disc photocatalytic reactor (SDPR) equipped with a visible light-activated Fe
O
@SiO
-NH
@CuO/ZnO core-shell (FSNCZ CS) thin film photocatalyst was investigated for the decomposition of amoxicillin (AMX), a representative antibiotic. Various characterization techniques, such as TEM, FESEM, EDX, AFM, XRD, and UV-Vis-DRS, were employed to study the surface morphology, optoelectronic properties, and nanostructure of the FSNCZ CS. Key operating parameters such as irradiation time, pH, initial AMX concentration, rotational speed, and solution flow rate were fine-tuned for optimization. The results indicated that the highest AMX decomposition (98.7%) was attained under optimal conditions of 60 min of irradiation time, a rotational speed of 350 rpm, a solution flow rate of 0.9 L/min, pH of 5, and an initial AMX concentration of 20 mg/L. Moreover, during the 60 min irradiation time, more than 69.95% of chemical oxygen demand and 61.2% of total organic carbon were removed. After the photocatalytic decomposition of AMX, there is a substantial increase in the average oxidation state and carbon oxidation state in SDPR from 1.33 to 1.94 and 3.2, respectively. Active species tests confirmed that ·OH and ·O
played a dominant role in AMX decomposition. The developed SDPR, which incorporates a reusable and robust FSNCZ CS photocatalyst, demonstrates promising potential for the decomposition of organic compounds.
Here, a combined pretreatment oxidation process (O3/H2O2) was investigated to enhance the biodegradability of raw landfill leachate (RLL) and biomethane potential (BMP) in anaerobic reactors. The ...central composite design (CCD) and response surface methodology (RSM) were employed to optimize the operational parameters influencing on RLL bioavailability in O3/H2O2 process: pH, Oxygen Flow rate, Reaction Time, and H2O2 concentration. The findings revealed that the O3/H2O2 increased biodegradability index (BOD5/COD) of RLL from 0.41 to 0.68 under optimized condition (pH=8, Oxygen flow= 0.25 L.min−1, Reaction Time= 25 min, H2O2 concentration= 2.5 g.L−1). Furthermore, the effects of O3/H2O2 process on BMP of RLL were surveyed under mesophilic anaerobic reactors (Temperature: 37 ± 1 °C) in viewpoints of operational performance and methane yield in a batch mode for incubation period of 24 days. The results showed that O3/H2O2 process simultaneously improve the BMP by 2.99 times higher in a shorter lag-phase period (5 days) compared with control. The pretreatment O3/H2O2 and mesophilic anaerobic digestion process revealed a feasible and efficient method for enhance BMP of RLL.
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•Oxidation pretreatment process (O3/H2O2) was employed to enhance RLL bioavailability.•O3/H2O2 revealed efficient technology to lower lag-phase of RLL anaerobic digestion.•Methane yield of 0.158 LH4/gsCOD removed achieved from O3/H2O2-assisted anaerobic reactor.
This study investigated the recycling of freshly-smoked cigarette butts (FCBs) and unsmoked cigarette filters (UCFs) into a cellulose acetate (CA) membrane. The both samples were prepared by means of ...a combination of seven cigarette brands, and the phase inversion method was used to recycle each sample into a membrane using N-methyl-2-pyrrolidone. The efficiency of the prepared membranes for the removal of chromium, cadmium, and lead from an aqueous solution in a forward osmosis reactor was investigated. The results showed that the both membranes had a smooth surface and macrovoids. The flux of the prepared membranes from the UCFs and FCBs recycling were 14.8 and 13.2 LMH, respectively. The porosity and reverse salt of the UCFs membrane were 61% and 3.5 gMH, while those for FCBs membrane were 58% and 3.9 gMH. The observed metal removal efficiency of the both membranes was in the range of 85 to 90%. However, increasing the concentration of metals up to five times caused a slight decrease in the removal efficiency (less than 5%).
The enhancement of composting technology to stabilize sludge pretreated by ozonation and ultrasonic was tested for 35 days. Secondary sludge produced by biological process are characterized with ...endogenous residue and inert solid matter which inhibit fully degrade bacterial cell walls. The composting process was performed with sludge pretreated with ozonatian and ultrasonics and green waste in a ratio of 2:1. The composting characteristics was evaluated for different physico-chemical and microbiological parameters in five different reactors. A high degree of composting quality was achieved with respect to significant reduction in volatile solids (VS) (32%), total organic carbon (TOC) (35.0%), C/N ratio (23.74), total coliform (TC) (168) along with the substantial increase in availability of nutrients like N (1.2%) and P (8.77%). High removal efficiency of TC and Fecal Coliform (FC) were observed in composting results, where simultaneous ultrasonic and ozonation were considered as primary-stabilization process. Therefore, applying integrated ultrasonic/ozonation with composting system for sludge stabilization is potentially useful technology in sustainable land restoration practices to meet standards and produce soil conditioner.
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