- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Photocatalytic degradation of organic pollutants from wastewater using aluminium doped titanium dioxide
摘要： The objective of this research was to study the performance of batch and continuous recirculating reactor to photo-degrade dye and synthetic wastewater. Here, Aluminium (Al) was used as the doped metal. The commercially available TiO2 P-25 and Al (NO3)3 was used as a Ti-precursor and doping agent, respectively, via the impregnation method. Various parameters such as the concentration of the doping agent, and calcination temperature were studied. The TiO2 nanocrystal doped with Al was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analyzer (TGA). The photocatalytic performance of Al-doped nanoparticle was quantified by the degradation of methylene blue (MB) solution under a visible light irradiation condition. Its performance was compared against undoped-nano-TiO2. The results showed that Al (NO3)3 solution with a concentration of 0.25% and volume of 100 cm/ml, and calcined at 300 C for 4 h, was the optimum condition of Al-doped nano-TiO2. Furthermore, the highest pseudo-first-order kinetic rate was 0.096 where the doped Al(NO3)3 of 0.75 w/v was used in the batch reactor. The Al-doped nano-TiO2 that was obtained has the potential for use as a photocatalyst for degradation organics pollutant from wastewater under the visible light irradiation. The highest removal of organic pollutants from synthetic wastewater was 75% using TiO2 P-25 alone at 2 g/L dosage. In addition, the removal of organic pollutant by TiO2/doped with Al was 80% at a dosage of 0.5 g/L and was 85% at a dosage of 1 g/L.
关键词： Batch reactor,Photo-catalyst,Titanium dioxide,Advanced oxidation process
更新于2025-09-23 15:23:52
-
Experimental data on the degradation of caffeine by photo-electro-fenton using BDD electrodes at pilot plant
摘要： Emerging contaminants (EC) are an imminent risk due to potential toxicity to aquatic ecosystems and human beings. This type of contaminants is found in low concentrations and usually present incomplete or inefficient removal by conventional treatments, which entail its permanence and constant increase. Advanced Oxidation Processes (AOP) are an alternative for the elimination of dangerous and resistant substances in wastewater. So, this research evaluates the caffeine degradation in aqueous solution by AOP, such as: Fenton, Electro-Oxidation (EO) with boron doped diamond (BDD) electrodes, Electro-Fenton (EF) and Photo-Electro-Fenton (PEF). The influences of pH, concentration of the supporting electrolyte and specific electric charge were investigated using a Taguchi's factorial design, which allowed to identify the contribution of each variable in the process. The data obtained in this work can be useful for scaling process and cost analysis because it provide the information at pilot plant scale.
关键词： Chemical engineering,Taguchi design,BDD electrodes,Advanced oxidation process,Caffeine degradation
更新于2025-09-23 15:23:52
-
Degradation and inactivation of adenovirus in water by photo-electro-oxidation
摘要： The present study analyzed the efficiency of the photo-electro-oxidation process as a method for degradation and inactivation of adenovirus in water. The experimental design employed a solution prepared from sterile water containing 5.107 genomic copies/L (gc/L) of a standard strain of human adenovirus type 5 (HAdV-5) divided into two equal parts, one to serve as control and one treated by photo-electro-oxidation (PEO) for 3 hours and with a 5A current. Samples collected throughout the exposure process were analyzed by real-time polymerase chain reaction (qPCR) for viral genome identification and quantitation. Prior to gene extraction, a parallel DNAse treatment step was carried out to assess the integrity of viral particles. Integrated cell culture (ICC) analyses assessed the viability of infection in a cell culture. The tested process proved effective for viral degradation, with a 7 log10 reduction in viral load after 60 minutes of treatment. The DNAse-treated samples exhibited complete reduction of viral load after a 75 minute exposure to the process, and ICC analyses showed completely non-viable viral particles at 30 minutes of treatment.
关键词： advanced oxidation process,water,adenovirus,photo-electro-oxidation
更新于2025-09-23 15:22:29
-
From micro to macro-contaminants: The impact of low-energy titanium dioxide photocatalysis followed by filtration on the mitigation of drinking water organics
摘要： This study evaluated strategies targeting macro- and micro-organic contaminant mitigation using low-energy titanium dioxide photocatalysis. Energy inputs of 1, 2, and 5 kWh m-3 resulted in incomplete oxidation of macro-organic natural organic matter, signified by greater reductions of UV254 and specific ultraviolet UV absorbance (SUVA) in comparison to dissolved organic carbon (DOC). The rate of UV254 removal was 3 orders of magnitude greater than the rate of DOC degradation. Incomplete oxidation improved operation of downstream filtration processes. Photocatalysis at 2 kWh m-3 increased the bed life of downstream granular activated carbon (GAC) filter by 340% relative to direct filtration pretreatment. Likewise, photocatalysis operated ahead of microfiltration decreased fouling, resulting in longer filter run times. Using 2 kWh m-3 photocatalysis increased filter run time by 36 times in comparison to direct filtration. Furthermore, levels of DOC and UV254 in the membrane permeate improved (with no change in removal across the membrane) using low-energy photocatalysis pretreatments. While high-energy UV inputs provided high levels of removal of the estrogenic micro-organics estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynlestradiol (EE2), low-energy photocatalysis did not enhance removal of estrogens beyond levels achieved by photolysis alone. In the cases of E1 and E3, the addition of TiO2 as a photocatalyst reduced degradation rates of estrogens compared to UV photolysis. Overall, process electrical energy per order magnitude reductions (EEOs) greatly improved using photocatalysis, versus photolysis, for the macro-organics DOC, UV254, and SUVA; however, energy required for removal of estrogens was similar between photolysis and photocatalysis.
关键词： granular activated carbon (GAC),estrogens,UV photolysis,dissolved organic carbon (DOC),advanced oxidation process (AOP),natural organic matter (NOM)
更新于2025-09-23 15:21:01
-
Pulsed light for a cleaner dyeing industry: Azo dye degradation by an advanced oxidation process driven by pulsed light
摘要： Water pollution by wastewater containing dyes is an environmental issue that can be mitigated by the use of advanced oxidation processes (AOP). Pulsed light (PL) is an emerging food processing technology that uses eco-friendly lamps and can potentially be adapted as light source of an UV-based AOP. In the present work, a PL/H2O2 process was tested for the decolourization of two azo dyes, and a pulsed light/H2O2/ferrioxalate process was tested for the decolourization of one azo dye. The efficiency of the PL/H2O2 process in a batch reactor under different parametric values: dye concentration, pH, H2O2 and salt doses was followed by spectrophotometry and fitted to first-order kinetics; and several degradation products were detected. In the PL/H2O2 process, decolourization rates increased at low dye concentrations and high H2O2 doses, were pH-dependent and were inhibited by the addition of NaCl, Na2SO3 or Na2CO3. More than 50 % decolouration was achieved with the PL/H2O2 process for both dyes after applying 54 J/cm2 (25 light pulses). The PL/H2O2/ferrioxalate process achieved > 95 % decolouration for Methyl orange when applying 21 J/cm2 (10 pulses); that level of energy can be supplied by PL commercial systems in nine and four seconds respectively. No known toxic degradation products were detected. Results show that a PL/H2O2 process has potential to be used for the efficient degradation of dyes from wastewater. Furthermore, the efficacy of this process can be improved by the use of ferrioxalate. PL technology could become an alternative light source to contribute to decrease the environmental impact of wastewater produced by the dyeing industry.
关键词： pulsed light,ferrioxalate,advanced oxidation process,azo dye,wastewater remediation
更新于2025-09-19 17:15:36
-
Facile, Gram-Scale and Eco-friendly Synthesis of Multi-Color Graphene Quantum Dots by Thermal-Driven Advanced Oxidation Process
摘要： Graphene quantum dots (GQDs) have been demonstrated of great potential and benefits in the fields of bioimaging and white light-emitting-diodes (WLEDs). However, it is still highly demanding at the current level to solve the dilemma of achieving high-yield GQDs of good quality and superior fluorescent property using low-cost sustainable and industrializable production procedure. In this work, we for the first time report the gram-scale synthesis of well-crystalline GQDs with ultra-small size based on thermal-driven Advanced Oxidation Process (AOP) under facile green hydrothermal conditions. The average yield calculated from 20 trials reached up to 60%, and the average size of the dots was measured to be ~3.7 nm. Furtherly, GQDs with the photoluminescence (PL) emission of blue, green, yellow, orange, and red have been prepared by expanding the π-conjugation and introducing graphite nitrogen in the carbon skeleton based on chemical structure engineering. The PL-tunable GQDs have an average size distribution of 2~5 nm and a lamellar structure of 2~6 layers. Structure analysis results have indicated that the red shift of PL emission is attributed to bandgap narrowing. This approach successfully converts the easily available and cheap precursor into high-valued products with great application potentials. The PL-tunable GQDs have been successfully used as fluorescent probes of good biocompatibility for in vitro/ in vivo bio-imaging and to produce highly-photostable white-light-emitting composite film with a quantum yield (QY) of 24%.
关键词： Gram-scale synthesis,White light-emitting-diodes,Photoluminescence,Bioimaging,Advanced Oxidation Process,Graphene quantum dots
更新于2025-09-19 17:13:59
-
In situ photoelectrochemical activation of sulfite by MoS2 photoanode for enhanced removal of ammonium nitrogen from wastewater
摘要： The advanced oxidation processes (AOPs) based on oxysulfur radicals (SO3??, SO4?? and SO5??) has been receiving growing attention in wastewater treatment. In this study, we report the in situ photoelectrochemical activation of sulfite to produce oxysulfur radicals with MoS2 nanosheets as a wide spectrum absorptive photoanode. At alkaline condition, the selective and efficient conversion of ammonia to dinitrogen was exclusively achieved in the presence of sulfite electrolyte under visible light irradiation. The sulfite plays multiple roles such as working as hole scavenger for improving stability of MoS2 electrode by inhibiting photo-corrosion and serving as precursor of oxysulfur radicals in the meantime. The influences of radical scavenger, dissolved oxygen and electrolyte on the photoelectrochemical, electrochemical and photochemical conversion of ammonia verified that oxysulfur radicals are more powerful than hydroxyl radicals in terms of ammonia conversion. The proposed system appears to be applicable to in situ treatment of wastewater containing of ammonia and sulfite pollutants, such as wastewater from ammonia-absorption-desulfurization of combustion smoke. This work also provides a new protocol in the design of new AOPs, where oxysulfur radicals can work together with hydroxyl radicals for simultaneous pollutants degradation and detoxification.
关键词： photoelectrocatalysis,sulfite activation,MoS2,advanced oxidation process,ammonia oxidation
更新于2025-09-10 09:29:36
-
Degradation of bisphenol-a using a sonophoto Fenton-like hybrid process over a LaFeO$_{3}$ perovskite catalyst and a comparison of its activity with that of a TiO$_{2}$ photocatalyst
摘要： Oxidation of bisphenol-A (BPA) was investigated using a sonophoto Fenton-like hybrid process under visible light irradiation in the presence of iron-containing perovskite LaFeO3 catalysts. For this purpose, firstly the perovskite catalyst (LaFeO3) was prepared by the sol-gel method and calcined at different temperatures (500, 700, and 800 ?C). The prepared catalysts were characterized using XRD, SEM, FTIR, nitrogen adsorption, UV-vis DRS, and ICP/OES measurements. Among the prepared catalysts the catalyst that was calcined at 500 ?C showed better catalytic activity with respect to degradation and chemical oxygen demand (COD) reduction (of 21.8% and 11.2%, respectively, after 3 h of reaction duration) than the other catalysts calcined at 700 ?C and 800 ?C. The catalytic activity of the LaFeO3 perovskite catalyst calcined at 500 ?C was compared with that of a TiO2 photocatalyst containing Fe and prepared by the sol-gel method. Better photocatalytic activity in terms of degradation of BPA, total organic carbon (TOC), and COD reductions was observed with the LaFeO3 perovskite catalyst under visible light. The degradation, COD, and TOC reductions after 6 h of oxidation were 34.8%, 26.9%, and 8.8% for the LaFeO3 perovskite catalyst, and 33.1%, 19.7%, and 4.9% for the Fe/TiO2 catalyst, respectively.
关键词： perovskite catalyst,Bisphenol-A,sonophoto Fenton-like process,hybrid advanced oxidation process
更新于2025-09-10 09:29:36
-
Synthesis and characterization of Poly (azomethine)/ ZnO nanocomposite towards photocatalytic degradation of Methylene blue, Malachite green and Bismarck brown
摘要： This research was carried out based on the significance of protecting the environment by preventing the contamination of water caused from effluents discharge from dyeing industries, effective nanocomposite were prepared to solve this problem. The poly(azomethine), ZnO and poly(azomethine)/ZnO nanocomposites were prepared and characterized by Fourier Transform-Infra red spectroscopy, UV-Visible spectroscopy, Powder X-ray diffraction, EDAX, SEM and TEM techniques. Methylene blue, malachite green and Bismarck brown were degraded from water using poly (azomethine) (PAZ), Zinc oxide (ZnO), PAZ/ZnO (PNZ) nano composites as photocatalyst in presence of natural sunlight. The degradation efficiency and reaction kinetics was calculated and the outcome of the photocatalytic experiments proved that the PAZ/ZnO nanocomposites reveals excellent photocatalytic activity and effective for decolorisation of dye containing waste water than PAZ and ZnO in presence of natural sunlight. The maximum degradation efficiency 97%, 96% and 95% was obtained for PNZ nanocomposites at optimum dosage of catalyst as 500 mg and 50 ppm of methylene blue, malachite green and Bismarck brown dye concentration respectively. The maximum degradation time was 5 h. After photocatalytic study the samples were characterized by FT-IR and UV-Visible spectroscopy.
关键词： degradation efficiency,advanced oxidation process,Poly(azomethine),ZnO,Nanocomposites,Photocatalyst
更新于2025-09-10 09:29:36
-
Degradation of cyanotoxins (microcystin) in drinking water using photoelectrooxidation
摘要： The discharge of sewage and industrial effluents containing high concentrations of pollutants in water bodies increases eutrophication. Cyanobacteria, some of the organisms whose growth is promoted by high nutrient concentrations, are resistant and produce several types of toxins, known as cyanotoxins, highly harmful to human beings. Current water treatment systems for the public water supply are not efficient in degradation of toxins. Advanced oxidation processes (AOP) have been tested for the removal of cyanotoxins, and the results have been positive. This study examines the application of photoelectrooxidation in the degradation of cyanotoxins (microcystins). The performance of the oxidative processes involved was evaluated separately: Photocatalysis, Electrolysis and Photoelectrooxidation. Results showed that the electrical current and UV radiation were directly associated with toxin degradation. The PEO system is efficient in removing cyanotoxins, and the reduction rate reached 99%. The final concentration of toxin was less than 1 μg/L of microcystin in the treated solution.
关键词： microcystin,advanced oxidation process,photoelectrooxidation,cyanotoxin
更新于2025-09-10 09:29:36