13 research outputs found

    Developing a Slow-Release Permanganate Composite for Degrading Aquaculture Antibiotics

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    Copious use of antibiotics in aquaculture farming systems has resulted in surface water contamination in some countries. Our objective was to develop a slow-release oxidant that could be used in situ to reduce antibiotic concentrations in discharges from aquaculture lagoons. We accomplished this by generating a slow-release permanganate (SR-MnO4-) that was composed of a biodegradable wax and a phosphate-based dispersing agent. Sulfadimethoxine (SDM) and its synergistic antibiotics were used as representative surrogates. Kinetic experiments verified that the antibiotic-MnO4- reactions were first-order with respect to MnO4- and initial antibiotic concentration (second-order rates: 0.056–0.128 s-1 M-1). A series of batch experiments showed that solution pH, water matrices, and humic acids impacted SDM degradation efficiency. Degradation plateaus were observed in the presence of humic acids (\u3e20 mgL-1), which caused greater MnO2 production. A mixture of KMnO4/beeswax/paraffin (SRB) at a ratio of 11.5:4:1 (w/w) was better for biodegradability and the continual release of MnO4-, but MnO2 formation altered release patterns. Adding tetrapotassium pyrophosphate (TKPP) into the composite resulted in delaying MnO2 aggregation and increased SDM removal efficiency to 90% due to the increased oxidative sites on the MnO2 particle surface. The MnO4- release data fit the Siepmann–Peppas model over the long term (t \u3c 48 d) while a Higuchi model provided a better fit for shorter timeframes (t \u3c 8 d). Our flow-through discharge tank system using SRB with TKPP continually reduced the SDM concentration in both DI water and lagoon wastewater. These results support SRB with TKPP as an effective composite for treating antibiotic residues in aquaculture discharge water

    Enrofloxacin and Sulfamethoxazole Sorption on Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, and Antibacterial Activity toward \u3ci\u3eS. aureus\u3c/i\u3e ATCC 25923

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    Excessive antibiotic use in veterinary applications has resulted in water contamination and potentially poses a serious threat to aquatic environments and human health. The objective of the current study was to quantify carbonized leonardite (cLND) adsorption capabilities to remove sulfamethoxazole (SMX)- and enrofloxacin (ENR)-contaminated water and to determine the microbial activity of ENR residuals on cLND following adsorption. The cLND samples prepared at 450oC and 850oC (cLND450 and cLND550, respectively) were evaluated for structural and physical characteristics and adsorption capabilities based on adsorption kinetics and isotherm studies. The low pyrolysis temperature of cLND resulted in a heterogeneous surface that was abundant in both hydrophobic and hydrophilic functional groups. SMX and ENR adsorption were best described using a pseudo-second-order rate expression. The SMX and ENR adsorption equilibrium data on cLND450 and cLND550 revealed their better compliance with a Langmuir isotherm than with four other models based on 2.3-fold higher values of qmENR than qmSMX. Under the presence of the environmental interference, the electrostatic interaction was the main contributing factor to the adsorption capability. Microbial activity experiments based on the growth of Staphylococcus aureus ATCC 25923 revealed that cLND could successfully adsorb and subsequently retain the adsorbed antibiotic on the cLND surface. This study demonstrated the potential of cLND550 as a suitable low-cost adsorbent for the highly efficient removal of antibiotics from water

    Response surface optimization and social impact evaluation of Houttuynia cordata Thunb solar drying technology for community enterprise in Chiangrai, Thailand

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    Drying has emerged as one of the most important ways of preserving high-quality and quantity food goods. A force convection solar drying is considered an ecologically and environmentally friendly alternative. This research presents parameter optimization of greenhouse tunnel dryer  of  Houttuynia cordata Thunb (H. cordata) using response surface methodology with the assessment of economic feasibility and social return on invesment. The influence parameters of the drying process were evaluated to obtain maximum efficiency. The individual parameters were temperature (40 – 60 °C), material length (10 – 30 cm), and relative humidity (30 – 50%). The individual parameters of drying temperature showed an extreme effect on the response of moisture content and color value change, while the relative humidity had only an influence on moisture content. On the other hand, the parameter of material length was not significance in both responses. When compared to open-air drying, solar drying reduced the drying time of H. cordata by 57.14%. The payback period of the dryer was found to be 2.5 years. Furthermore, the results reveal that the social return on investment ratio in 2021 was 2.18, then increasing to 2.52 in 2022 and 2.91 in 2023. According to the findings, solar drying technology has the potential to be an adequate product quality improvement technology for H. cordata. It is a feasible drying technology in terms of economic evaluation

    Implementation of an Integrated Floating Wetland and Biofilter for Water Treatment in Nile Tilapia Aquaculture

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    Due to the high nutrient and organic matter contents of fish pond water, the water must be treated before disposal to prevent the eutrophication and deterioration of natural receiving waters. Floating wetlands (FTWs) and biofilters are environmentally friendly ecological treatments that can be used for this water. Thus, this study aimed to investigate the performance of FTWs with biofilters (FTW/Bs) for nutrient and organic compound removal. Two FTW/ Bs were applied in a pond with 5,000 Nile tilapia. The macrophyte species in the FTWs were Cyperus (Cyperus spp.) and Heliconia (Heliconia spp.). The buoyant mats of the FTWs were made from bamboo, and 200 bioballs were loaded below the mats. The water quality parameters in the pond were monitored for 5 weeks between the control test without the FTW/Bs and the experimental test with FTW/Bs at sites 1 (S1) to 8 (S8). The FTW/Bs were located at sites 2 (S2) and 3 (S3). The results showed reductions in all water quality parameters except orthophosphate (ortho-P) at S2 and S3. The COD, BOD, NH4-N, and SS at S2 and S3 parameters during the experimental test were significantly lower than those during the control test, in the ranges of 20.34–33.96, 25.47–29.41, 25.86–27.87, and 26.00–28.44%, respectively

    Dataset on the optimization by response surface methodology for dried banana products using greenhouse solar drying in Thailand

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    The banana industry in Thailand holds immense potential, driven by favorable growing conditions, robust domestic consumption, and active participation in the export market. Solar dryers have the potential to revolutionize fruit processing by providing a sustainable, cost-effective, and nutritionally rich solution. This research aims to optimize the greenhouse solar drying process for bananas using response surface methodology. The specific variables under investigation are drying temperature and drying time. A designed greenhouse solar dryer, tailored for commercial use in the target area, was employed for the experiment. Statistical analysis and response surface methodology were utilized to evaluate the effects of the experimental variables on two key outputs: moisture content and color change of the dried banana product. The findings of this study contribute to a deeper understanding of the potential of solar drying in the context of banana processing. The research outcomes provide valuable insights for optimizing the solar drying process, thereby facilitating the development of the banana industry and its applicability

    Enhanced Photo-Fenton Activity Using Magnetic Cu<sub>0.5</sub>Mn<sub>0.5</sub>Fe<sub>2</sub>O<sub>4</sub> Nanoparticles as a Recoverable Catalyst for Degrading Organic Contaminants

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    Interest in using various nanoparticle catalysts to activate H2O2 with light for organic contaminant and wastewater treatment is steadily increasing. We successfully synthesized magnetically recoverable Cu0.5Mn0.5Fe2O4 nanoparticles using a simple co-precipitation method followed by melamine-assisted calcination. Material characterization revealed that melamine acted as a coordinating agent during the calcination process that promoted a ferrite structure. Copper (Cu)-substitution effectively decreased material aggregation and promoted catalytic activities. Cu0.5Mn0.5Fe2O4 nanoparticles showed outstanding catalytic performance on several organic contaminants (87.6–100.0% removal within 2 h). Using oxytetracycline (OTC) as a surrogate wastewater constituent, we found that the hydroxyl radical (•OH) and superoxide anions (•O2−) were the active radical species involved in OTC degradation. Cu0.5Mn0.5Fe2O4 nanoparticles exhibited excellent photo-Fenton catalytic ability in real wastewater and demonstrated high material stability, even after four consecutive uses (i.e., fourth cycle). In a pilot-scale experiment (10 L), we provide proof that our rigorous treatment system was able to remove remnant OTC, TOC, and also any available colloidal particles to only 1 NTU. Ecotoxicity studies using an aquatic plant (Hydrilla verticillata) and zooplankton revealed that treated water could be reused in various ratios. Furthermore, at 5% of treated water, rapid leaf recovery and a significant increase in rotifer numbers were reported. These observations support the use of Cu0.5Mn0.5Fe2O4/H2O2/light as an efficient and environmentally friendly catalytic system for treatment of organic contaminants, and a radical generating mechanism is proposed

    Developing a Slow-Release Permanganate Composite for Degrading Aquaculture Antibiotics

    No full text
    Copious use of antibiotics in aquaculture farming systems has resulted in surface water contamination in some countries. Our objective was to develop a slow-release oxidant that could be used in situ to reduce antibiotic concentrations in discharges from aquaculture lagoons. We accomplished this by generating a slow-release permanganate (SR-MnO4−) that was composed of a biodegradable wax and a phosphate-based dispersing agent. Sulfadimethoxine (SDM) and its synergistic antibiotics were used as representative surrogates. Kinetic experiments verified that the antibiotic-MnO4− reactions were first-order with respect to MnO4− and initial antibiotic concentration (second-order rates: 0.056–0.128 s−1 M−1). A series of batch experiments showed that solution pH, water matrices, and humic acids impacted SDM degradation efficiency. Degradation plateaus were observed in the presence of humic acids (>20 mgL−1), which caused greater MnO2 production. A mixture of KMnO4/beeswax/paraffin (SRB) at a ratio of 11.5:4:1 (w/w) was better for biodegradability and the continual release of MnO4−, but MnO2 formation altered release patterns. Adding tetrapotassium pyrophosphate (TKPP) into the composite resulted in delaying MnO2 aggregation and increased SDM removal efficiency to 90% due to the increased oxidative sites on the MnO2 particle surface. The MnO4− release data fit the Siepmann–Peppas model over the long term (t < 48 d) while a Higuchi model provided a better fit for shorter timeframes (t < 8 d). Our flow-through discharge tank system using SRB with TKPP continually reduced the SDM concentration in both DI water and lagoon wastewater. These results support SRB with TKPP as an effective composite for treating antibiotic residues in aquaculture discharge water

    Enhanced Photo-Fenton Activity Using Magnetic Cu\u3csub\u3e0.5\u3c/sub\u3eMn\u3csub\u3e0.5\u3c/sub\u3eFe\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e4\u3c/sub\u3e Nanoparticles as a Recoverable Catalyst for Degrading Organic Contaminants

    Get PDF
    Interest in using various nanoparticle catalysts to activate H2O2 with light for organic contaminant and wastewater treatment is steadily increasing. We successfully synthesized magnetically recoverable Cu0.5Mn0.5Fe2O4 nanoparticles using a simple co-precipitation method followed by melamine-assisted calcination. Material characterization revealed that melamine acted as a coordinating agent during the calcination process that promoted a ferrite structure. Copper (Cu)-substitution effectively decreased material aggregation and promoted catalytic activities. Cu0.5Mn0.5Fe2O4 nanoparticles showed outstanding catalytic performance on several organic contaminants (87.6–100.0% removal within 2 h). Using oxytetracycline (OTC) as a surrogate wastewater constituent, we found that the hydroxyl radical (•OH) and superoxide anions (•O2−) were the active radical species involved in OTC degradation. Cu0.5Mn0.5Fe2O4 nanoparticles exhibited excellent photo-Fenton catalytic ability in real wastewater and demonstrated high material stability, even after four consecutive uses (i.e., fourth cycle). In a pilot-scale experiment (10 L), we provide proof that our rigorous treatment system was able to remove remnant OTC, TOC, and also any available colloidal particles to only 1 NTU. Ecotoxicity studies using an aquatic plant (Hydrilla verticillata) and zooplankton revealed that treated water could be reused in various ratios. Furthermore, at 5% of treated water, rapid leaf recovery and a significant increase in rotifer numbers were reported. These observations support the use of Cu0.5Mn0.5Fe2O4/H2O2/light as an efficient and environmentally friendly catalytic system for treatment of organic contaminants, and a radical generating mechanism is proposed

    Optimization of Liquid Hot Water Pretreatment and Fermentation for Ethanol Production from Sugarcane Bagasse Using <i>Saccharomyces cerevisiae</i>

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    Sugarcane bagasse can be considered a potential raw material in terms of quantity and quality for the production of alternative biofuels. In this research, liquid hot water (LHW) was studied as a pretreatment process to enhance the digestibility of pretreated material for further conversion into bioethanol. Different variables (temperature, residual time, and acid concentration) were determined to predict the optimized condition. LHW pretreatment showed an impact on the hemicellulose structure. The optimized condition at 160 °C for 60 min with 0.050 M acid concentration reached the highest glucose yield of 96.86%. Scanning electron microscopy (SEM) showed conspicuous modification of the sugarcane bagasse structure. The effect of LHW pretreatment was also demonstrated by the changes in crystallinity and surface area analysis. FTIR techniques revealed the chemical structure changes of pretreated sugarcane bagasse. The prepared material was further converted into ethanol production with the maximized ethanol concentration of 19.9 g/L

    Enrofloxacin and Sulfamethoxazole Sorption on Carbonized Leonardite: Kinetics, Isotherms, Influential Effects, and Antibacterial Activity toward <i>S. aureus</i> ATCC 25923

    No full text
    Excessive antibiotic use in veterinary applications has resulted in water contamination and potentially poses a serious threat to aquatic environments and human health. The objective of the current study was to quantify carbonized leonardite (cLND) adsorption capabilities to remove sulfamethoxazole (SMX)- and enrofloxacin (ENR)-contaminated water and to determine the microbial activity of ENR residuals on cLND following adsorption. The cLND samples prepared at 450 °C and 850 °C (cLND450 and cLND550, respectively) were evaluated for structural and physical characteristics and adsorption capabilities based on adsorption kinetics and isotherm studies. The low pyrolysis temperature of cLND resulted in a heterogeneous surface that was abundant in both hydrophobic and hydrophilic functional groups. SMX and ENR adsorption were best described using a pseudo-second-order rate expression. The SMX and ENR adsorption equilibrium data on cLND450 and cLND550 revealed their better compliance with a Langmuir isotherm than with four other models based on 2.3-fold higher values of qmENR than qmSMX. Under the presence of the environmental interference, the electrostatic interaction was the main contributing factor to the adsorption capability. Microbial activity experiments based on the growth of Staphylococcus aureus ATCC 25923 revealed that cLND could successfully adsorb and subsequently retain the adsorbed antibiotic on the cLND surface. This study demonstrated the potential of cLND550 as a suitable low-cost adsorbent for the highly efficient removal of antibiotics from water
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