Evaluation of solar photovoltaic carport canopy with electric vehicle charging potential.

While sustainable mobility and decarbonization of transportation sector are among the most comprehensive solutions to the problem of climate change, electric vehicles (EV) are becoming increasingly popular as the future mode of transport. In this study, the integration of a solar carport canopy to a potential EV charging station is analyzed using various operating conditions. A detailed analysis has been provided for the carport located in southern Taiwan, Kaohsiung city, where electricity generation, emission impacts, and financial analysis of the solar EV charging station are discussed. The results of a case study showed a potential of 140 MWh/year of solar energy yield, which could provide solar electricity of more than 3000 vehicles per month with 1-h parking time, generating 94% lower total carbon dioxide emission than the electricity produced from traditional grid methods. Taken into account the impact of carbon tax implementation on driver economics, the results demonstrated the viability of such photovoltaic (PV)-based charging stations, particularly for possible higher carbon tax scenarios in the future. The presented results can be implemented on a larger scale, offering guidelines and tools for constructing solar-powered EV charging station infrastructure.

Novel design of amine and metal hydroxide functional group modified onto sludge biochar for arsenic removal.

This study involved novel-designed sludge biochar (SB) adsorbed for arsenic removal with lower operating costs and higher adsorption efficiency properties. Generally, biochar only relies on micropores for pollutant adsorption, but physical adsorption is not highly efficient for arsenic removal. Therefore, in order to improve the removal efficiency of arsenic by SB, diethylenetriamine (DETA) and FeCl3 were used in this study to modify the surface of SB by an immersion method. The objectives of this research are to obtain optimum operation conditions by assessing the effect of different Fe content, pH and initial concentration on adsorbing arsenic. This study is the first to use Density Functional Theory (DFT) to simulate and verify the adsorption mechanism of arsenic by SB. Results showed the presence of amine/iron oxyhydroxides functional groups greatly promoted SB surface activity and its arsenic adsorption potential. The surface area, pore volume and pore size of the SB were estimated to be 525 m2 g-1, 0.35 cm3 g-1 and 8.71 nm, respectively. The DFT model result is the same as the result of arsenic adsorption performance with high adsorption energy (-246.3 kJmol-1) and shorter bond distances (1.42 Å), indicating strong chemical adsorption between arsenic and material. The reaction mechanism is divided into four pathways, including oxidation-reduction, complexation, electrostatic adsorption and pore adsorption.

Preparation of Metal Modified onto Biochar from Hazardous Waste for Arsenic Removal.

Use of urban sludge, hospital sludge, and aquatic product sludge as a biochar adsorbent from wastewater treatment plants was investigated. Microwave carbonization was used to carbonize the sludge and then chemically activated at high temperatures to increase porosity and surface area. Effective of arsenic adsorption in water presents a newly designed metal doped to biochar. The biochar was characterized by scanning electron microscope (SEM) with energy dispersive X-ray (EDS), nitrogen adsorption/desorption isotherm analyzer (BET), thermo gravimetric analysis (TGA) and X-ray diffraction (XRD) analysis. Results display uniform pore sizes and high surface area (>490 m²g-1) of the biochar. Thence, urban sludge, hospital sludge, and aquatic product sludge can be used as carbon sources. The highest amount of Fe, Mn, and Ni loading onto the biochar was determined to be 8.0%, 6.0% and 10.0%, respectively. All biochar samples have arsenic adsorption capacities positively correlated with initial concentration. The corresponding removal efficiency of As(V) is 98% and As(III) is 84% at pH 3 with an adsorption capacity of 4.12 and 3.6 mg g-1, respectively. The adsorption capacity of As(V) and As(III) clearly decreased in the presence of PO43- (2.34 and 1.46 mg g-1, respectively). Due to competition for adsorption sites, the PO43- can effectively reduce arsenic adsorption. The arsenic species adsorption-desorption recycles on biochar are also discussed.

A breakthrough dynamic-osmotic membrane bioreactor/nanofiltration hybrid system for real municipal wastewater treatment and reuse.

This study designed a Dynamic-Osmotic membrane bioreactor/nanofiltration (OsMBR/NF) system for municipal wastewater treatment and reuse. Results indicated that a continuously rotating FO module with 60 RPM in Dynamic-OsMBR system could enhance shear stress and reduce cake layer of foulants, leading to higher flux (50%) compared to Traditional-OsMBR during a 40-operation day. A negligible specific reverse salt flux (0.059 G/L) and a water flux of 2.86 LMH were recorded when a mixture of 0.1 M EDTA-2Na/0.1 M Na2CO3/0.9 mM Triton114 functioned as draw solution (DS). It was found that the Dynamic-OsMBR/NF hybrid system could effectively remove pollutants (∼98% COD, ∼99% PO43-P, ∼93% NH4+-N, > 99% suspended solids) from wastewater. In short, this developed system can be considered a breakthrough technology as it successfully minimizes membrane fouling by shear force, and achieves high water quality for reuse by two membrane- barriers.

Adsorption Configurations of Iron Complexes on As(III) Adsorption Over Sludge Biochar Surface.

Waste recycling and reuse will result in significant material and energy savings. In this research, usage of hospital sludge as a biochar adsorbent for wastewater treatment plants was investigated. Microwave carbonization was used to carbonize the sludge and then chemically activated with ZnCl2to increase surface area and porosity. A newly designed iron metal doped sludge biochar carbon (SBC) has effective adsorption of inorganic arsenic (As(III), As2O3) in water. The findings clearly demonstrate the viability and utility of using hospital sludge as a source of carbon to generate SBC. The adsorption mechanism of As(III) on SBC's iron-metal-modified surface has been studied using density functional theory (DFT) to understand the impact of functional complexes on adsorption As(III). Tests showed physical as well as chemical adsorption of As(III) on Fe-SBC surface. Fe's involvement in functional complexes greatly fostered SBC surface activity and it's As(III) adsorption ability. The physical adsorption energies of As(III) with Fe functional complexes on the SBC surface were -42.3 KJ mol-1. Other hand, the chemical adsorption energies of As(III) on Fe-SBC surface was -325.5 KJ mol-1. As(III) is capable of interacting in a bidentate fashion with the dopants through the protonated oxygen atoms and this conformation of the cyclic structure is higher in the adsorption energy than the others.

Aqueous Oxytetracycline and Norfloxacin Sonocatalytic Degradation in the Presence of Peroxydisulfate with Multilayer Sheet-Like Zinc Oxide.

Multilayer ZnO sheet-like flakes were synthesized by a simple method of precipitation and characterized by the techniques of X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The findings are proven that the SEM images show the overall morphology of a single sheet-like ZnO nanostructure made from uniformly thick nano-sheets. In an aqueous environment, the acoustic ability of the prepared material was assessed using ultrasound (US) radiation to degrade oxytetracycline (OTC) and norfloxacin (NF). To increase the degradation efficiency, a US/ZnO/peroxodisulfate system was developed by introducing ammonium persulfate ((NH4)2S2O8) and sodium persulfate (Na2S2O8), exhibiting excellent synergistic effects. Result show the decomposition efficiency for NF removal with Na2S2O8 (64%) appeared to be slightly better than with (NH4)2S2O8 (56%). By contrast, the ultrasonic catalytic efficiency of Na2S2O8 (98%) was slightly better than that of (NH4)2S2O8 (94%) for OTC removal. The addition of scavengers to the US/ZnO/peroxodisulfate system through the NF and OTC results in the largest effect of holes. The degradation is considered to be often caused by holes. In this system, the Na2S2O8 can have two roles to increase the rate of degradation: (1) The SO4- formed by Na2S2O8 under ultrasonic irradiation directly degraded to norfloxacin on ZnO surface; and (2) S2O82- behaved as an electron acceptor, inhibiting recombination of electron hole pairs, enabling the development of more ·OH. Therefore, the synergistic effect significantly increases US/ZnO/peroxodisulfate sonocatalytic activity (Hu, S.B., et al., 2017. Aqueous norfloxacin sonocatalytic degradation with multilayer flower-like ZnO in the presence of peroxydisulfate. Ultrasonics Sonochemistry, 38(1), pp.446-454).

Augmentation of Photocatalytic Degradation of Oxytetracycline by Cu-CdS and Deciphering the Contribution of Reactive Oxygen Species.

Production of Copper (Cu) modified Cadmium sulfide (CdS) nanomaterial, named as Cu-CdS, was successfully synthesized through hydrothermal and photo deposition method to degrade oxytetracycline (OTC) antibiotics in aqueous solution. Uniform surface loading of copper was observed on CdS using Scanning Electron Microscopy-mapping (SEM-mapping). The Cu induced improvement in the visible light absorption was observed using UV-vis absorption spectrum. Thus, this material can exhibit excellent oxytetracycline (OTC) degradation by photocatalysis. The best OTC degradation efficiency of 90% was be achieved under the optimal concentration of 4% Cu-CdS, with 0.1 g L-1 dosage (pH 5) under UV irradiation. 0.167 mg L-1 min-1 was observed as the reaction kL-H on the peripheral of the catalyst. In addition, OTC can also be degraded under visible light with removal efficiency approximately 90%. Moreover, the contribution of main reactive oxygen species (ROS), including hydroxyl radicals, superoxide radical and holes, is evaluated as 18%, 43% and 29%.

Feasibility Study of Activated Sludge/Contact Aeration Combined System Treating Oil-Containing Domestic Sewage.

Both activated sludge/contact aeration (AS/CA) and AS-only systems for treating oil-containing domestic sewage were tested. The results of these tests indicate that the oil and grease removal ratios of the AS/CA system exceeded those of the AS-only system. When the influent oil and grease concentration reached 60 mg/L, the effluent concentration of the AS system was 13 mg/L, which exceed 10 mg/L, the Taiwan Effluent Standard for oil and grease. However, in the AS/CA system, the effluent oil and grease concentration was 8 mg/L, which was below the required standard. This study analyzes the biological phases of the AS-only system and the combined AS/CA system using a scanning electronic microscope and a denatured gradient gel electrophoresis method when the inflow concentration of oil and grease is increased to 120 mg/L. The results of the Chemical Oxygen Demand (COD) experiment reveal that the AS/CA system is affected less than the AS system, and the COD removal rate of the AS/CA system is maintained at 81%, which exceeds that (61.5%) of the AS-only system. The analytical results thus obtained suggest that both the amounts of biological phase and the biomass in the combined AS/CA system exceed those of an AS-only system.

Regeneration and reuse of leachate from a municipal solid waste landfill.

Landfill leachate is deep brown in color with extremely complex composition and difficult to treat in order to meet the effluent standards. The leachate of Keelung City Tien Wai Tien landfill has an average flow of 350 CMD. In the present study following serially connected devices: Activated sludge/contact aeration (AS/CA) combined system, reverse osmosis (RO) and an ammonia stripping tower were used to treat the leachate. After treatment, the COD (removal rate of 91%), BOD (removal rate of 83%), SS (removal rate of 86%) and NH(4+)-N level (removal rate of 98%) significantly reduced in the leachate. The treated effluent was further recycled and used as RO back washing water and for sprinkling roads and watering plants in Keelung City. It is further required to evaluate whether the treated effluent can be reutilized for agriculture and extinguishing fire during shortage of water.

Photocatalytic degradation of reactive red 141 in the presence of Cr(VI) using TiO2 nanotubes.

TiO2 nanotubes were prepared by hydrothermal process, then characterized using Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-Visible spectroscopy measurements. The photodegradation performance assessment of Reactive Red 141 (RR141) with near visible light irradiation (lambda = 380 nm) was carried out under different catalyst doses, dye concentrations, pH and initial Cr(VI) concentrations by TiO2 powder and nanotubes. The results showed that the specific surface area of TiO2 nanotubes were 152 m2 g(-1), about three times larger than that of TiO2 powder which was roughly 51 m2 g(-1). The TiO2 nanotubes did not affect the lattice structure of the TiO2. The adsorption amount increases as the dosage and RR141 concentration increases. However, the decolonization efficiency decreased with increasing initial RR141 concentration. Results also showed that an acidic solution is more favorable for photocatalytic degradation of RR141. On the other hand, Cr(VI) can be adsorbed on the surface of TiO2 nanotubes to affect the decolonization efficiency of RR141.

Study on the degradation of the dye wastewater with polyaniline on titanium nanotubes.

Polyaniline/titanium nanotube composite (PANI/TNT) photocatalysts were prepared by 'in situ'chemical oxidative polymerization of aniline. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform IR spectra (FTIR) and UV-Visible spectroscopy measurements were used to characterize the obtained photocatalysts, and their photocatalytic activities were investigated by degrading Reactive Green19 (RG19) under near visible light irradiation (lambda = 365 nm). The content of PANI, pH, dosage, and concentration of RG19 were also investigated. The results showed that the inner diameter of the PANI/TNT was 6 nm and that the PANI did not change the structure of the TNT. The PANI was coated on the surface of the TNT. The light response of the PANI/TNT was extended to the visible-light regions. Among the six different kinds of photocatalysts, the 1.17 wt% PANI/TNT had the best performance in treating 10 ppm RG19. The best pH is 3 for the largely protonated surface of the composite at low pH. The adsorption amount was increased as the dosage increased. The decolonization efficiency decreased with increasing initial RG19 concentration. The performance of the photocatalyst in decomposing RG19 was stable after 5 time cycles.

Catalytic decomposition of CF4 over iron promoted mesoporous catalysts.

A series of mesoporous catalysts (MCM-41) promoted by iron nanoparticles were prepared by the co-precipitation method and tested for the decomposition of carbon tetrafluoride (CF4). The addition of iron oxide nanoparticles to MCM-41 led to an improvement in the catalytic activity for CF4 decomposition. The catalyst was the most active around 5 wt% iron added to MCM-41. Methods of X-ray Powder Diffractometer, Scanning Electron Microscope-Energy Dispersive Spectrometer, BET, and high resolution transmission electron microscopy were used to characterize the MCM-41 catalysts. The analytical results indicated that the addition of over 2 wt% iron nanoparticles increased the surface area of MCM-41, which was the rate-determining factor of CF4 decomposition over MCM-41 catalyst. In conclusion, the addition of iron was responsible for the enhancement of catalytic activity of MCM-41.