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Content available remote Microstructural, antifungal and photocatalytic activity of NiO–ZnO nanocomposite
EN
In this work, NiO–ZnOnanocomposite (NC)was prepared through a facile, low-temperature,sol–gel route. Zinc acetate dihydrate, nickel chloride hexahydrate, cetyltrimethyl ammonium bromide (CTAB), and citric acid were used in the synthesis of the material. Then, the sample was kept in the muffle furnace at a temperature of 600°C for 2 h. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), UV–Visible spectroscopy, and photocatalytic and antifungal investigations were used to characterize the synthesized nanocrystallites. The XRD data showedthe polycrystalline hexagonal ZnO nanoparticles and cubic NiO crystallites. FTIR studies confirmed the presence of Zn-O and Ni-O bonds in the sample. The FESEM analysis showed the morphology of nanocrystallitescharacterized by their homogeneous shape and size. The absorbance curves from the UV–Visible spectroscopy investigation revealed the bandgap of 3.17 eV. The research findings demonstrate that the NiO–ZnO NC possesses the significant level of selected microbial pathogens. Industrial dyesmake water unhealthy for drinking. Among these dyes, methylene blue (MB) is toxic, carcinogenic, and non-biodegradable, and causes a severe threat to human health and environmental safety. Hence, it is necessary to develop efficient and environmentally friendly technology to remove MB from wastewater. The ZnO–NiO NC degraded the MB dye pollutant under visible irradiation (125 W), according to photocatalytic tests. After 120 min of exposure, the photocatalytic investigations demonstrated 75% degradation efficiency.
EN
Produced water is one of the most dangerous types of pollution for the environment, specifically the soil, since it is full of oil, suspended particulates, dissolved compounds, and various other pollutants. This research describes the advanced oxidation process (AOPs) that were studied to purge the generated water from the Al Khabaz oilfield located in (Northern Iraq – Kirkuk governorate) of any oil content using two photocatalytic homogeneous and heterogeneous processes in the batch system under optimal conditions: homogeneous processes, including Photo-Fenton (hydrogen peroxide, ferrous sulfates, and ultraviolet light), and Fenton process (hydrogen peroxide, and ferrous sulfates), and Direct-Photolysis (ultraviolet only) were used studied the effects of hydrogen peroxide (H2O2) & ferrous sulfate (Fe+2), doses, irradiation time, pH Value, and intensity of UV to the oil removal efficiency. This work investigated the maximum efficiency in Photo Fenton = 85.68%, in Fenton = 75.01%, and in direct UV photolysis = 56.64%. The heterogeneous photocatalytic process (TiO2/UV) studied the effect of titanium dioxide (TiO2) nanoparticles doses and UV intensity. The results show that the optimal efficiency achieved was 60.95%. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier Transforms Infrared Spectroscopy (FT-IR) were used to look into the characteristics of the catalyst titanium dioxide nanoparticles. TiO2 NPs seemed to be spherical in the SEM test, and their FT-IR analysis absorption values ranged from 424.77 to 3403.71 cm-1. Their sizes varied between 31.57 and 38.40 nm, and XRD revealed details regarding their chemical composition.
EN
Improving the selectivity of photocatalysis of LDH pristine (MgAl-LDH) and LDH composite (MgAl-SiW12O40] and MgAl-[PW12O40]) was synthesized and used for degraded malachite green (MG). The effects of the amount of catalyst, pH value, and reaction times on degradation performance were discussed. MG degraded better composites than LDH pristine. The results indicated that MgAl-LDH was successfully synthesized by showing the peak diffractions at angles 10.39°(003), 20.17°(006), and 34.8°(009). Both kinds of attained MgAl-[SiW12O40] and MgAl-[PW12O40] had the typical structure of LDH that proved by appeared diffraction at 2θ angles 7.73°, 28.6°, 35.6° for MgAl-[PW12O40] and at 2θ angles 8.61°, 24.27°, 34.96° and 66.34° for MgAl-[SiW12O40]. The FTIR result indicates materials used for fifth regeneration, which confirmed the LDH composite structure. The photodegradation activity of MG for pristine MgAl LDH (56.1%), composites MgAl-Pw (84.6%) and MgAl-Si (87.8%), respectively. The successful ability of photodegradation process by the percentage of degradation on material LDH-polyoxometalate composite showed the increasing of photodegradation catalytic and the regeneration ability of LDH pristine.
EN
The synthesis and characterization of layered double hydroxide (LDH) and intercalated polyoxometalate were presented.. The growth of polyoxometalate on Ni/Mg layered double hydroxide for degradation procion red (PR) was reported. The degradation parameters and organic dye removal efficiency of Zn/Mg-LDH and both composite LDH-polyoxometalate were determined by considering factors such as pH of dye solution, catalyst dosage, and time as variables of degradation. X-Ray, FTIR, and SEM spectroscopy confirmed the layered double hydroxide structure. XRD and FTIR analysis confirmed the single-phase of the as-made and polyoxometalate intercalated LDH. SEM images show the formation of aggregates of small various sizes. The catalytic activity of the material was evaluated in the degradation of PR as a model pollutant. The result showed that MgAl-SiW12O40 has a good degradation capacity for PR as compared to MgAl-PW12O40, ZnAl-SiW12O40, and ZnAl-PW12O40. The result shows that the LDH composite presents stability and has good photocatalytic activities toward the reduction of methylene blue. The materials utilized for the fifth regeneration are indicated by the FTIR results, which verified the LDH composite structure. The photodegradation process of procion red for immaculate ZnAl-LDH, MgAl-LDH, ZnAl-[PW12O40], ZnAl-[SiW12O40], MgAl-[PW12O40], MgAl-[SiW12O40] amounted to 68%, 70%, 56%, 79%, 74%, and 80%, respectively. The capacity of LDH-polyoxometalate composite material to successfully photodegrade, as measured by the percentage of degradation, revealed an increase in photodegradation catalysis and the ability of LDH to regenerate.
EN
This study successfully synthesized a core-shell-shell in the form of CoFe2O4-SiO2-TiO2 catalyst magnetic and recyclable. The catalyst was employed for the photocatalytic degradation of methyl orange (MO) dye. Subsequently, the catalyst was subjected to XRD, FTIR, SEM-EDS, VSM, as well as UV-DRS characterizations. The photocatalytic degradation was studied as a function of the solution pH, MO concentration, and irradiation time, while the kinetics of photocatalytic degradation and the catalyst reusability were also evaluated. On the basis of the XRD, FTIR, and SEM-EDS characterizations, the CoFe2O4 coating was successfully carried out using SiO2 and TiO2. CoFe2O4-SiO2-TiO2 was discovered to possess magnetic properties with a saturation magnetization of 17.59 emu/g and a bandgap value of 2.4 eV. The photocatalytic degradation of MO followed the Langmuir-Hishelwood model. The optimum degradation was obtained at the MO concentration of 25 mg/L, solution pH of 4, catalyst dose of 0.05 g/L, irradiation time of 160 minutes, MO removal efficiency achieved 93.46%. The regeneration study showed CoFe2O4-SiO2-TiO2 after 5 cycles were able to catalyze the photocatalytic degradation with an MO removal efficiency of 89.96%.
PL
Właściwości samoczyszczące powierzchni cieszą się dużym zainteresowaniem ze względu na szerokie możliwości ich zastosowań w różnych gałęziach przemysłu (tekstylia, budownictwo, urządzenia sanitarne, części samochodowe, panele fotowoltaiczne, urządzenia elektroniczne, lotnictwo, kosmonautyka i in.). Powierzchnie samoczyszczące mogą mieć właściwości hydrofobowe lub hydrofilowe. Samoczyszczące tekstylia umożliwiają oszczędzanie wody, środków piorących, energii i czasu. Ponadto, są odporne na przenikanie wody i kumulowanie zanieczyszczeń na ich powierzchni. Opracowano metodę modyfikacji tkaniny bawełnianej w celu nadania jej właściwości samoczyszczących. Metoda ta opiera się na aplikacji poli(dimetylosiloksanu) oraz nanometrycznego dwutlenku tytanu na tkaninę bawełnianą.
EN
Self-cleaning properties of surfaces are of great interest due to the wide range of their applications in various industries (textiles, construction, sanitary equipment, automotive parts, photovoltaic panels, electronic devices, aviation, aerospace, etc.). Self-cleaning surfaces can have hydrophobic or hydrophilic properties. Self-cleaning textiles allow saving water, detergents, energy and time. Moreover, they are resistant to water penetration and accumulation of contaminants on their surface A method of modifying cotton fabric in order to make it self-cleaning has been developed. This method is based on the application of poly(dimethylsiloxane) with terminal hydroxyl groups and nanometric titanium dioxide to cotton fabric.
EN
The extraction of palm oil fruit (E. guineensis) is achieved by a combination of methods such as pressing, sterilizing, digesting, peeling, grading, purifying, and vacuum drying the extracted oil. This process requires excessive use of water and produces a large amount of wastewater with a high concentration of pollutants, called palm oil mill efluent (POME). This waste water is a high-viscosity liquid with a brown color and a temperature of 80–90 °C. It has a very low pH value, between 4.2–4.5, has a high chemical and biochemical oxygen demand, and is extremely toxic. POME treatment has adopted a variety of methods and technologies, including coagulation-flocculation, anaerobic-aerobic treatment and membrane technology. Biological treatment is mainly used to treat POME, and the POME treated through biological treatment is called palm oil mill secondary effluent (POMSE). Unfortunately, the treated wastewater still contains high concentrations of organic matter. The color of the effluent is still dark brown. The remaining pollutants from this biological process are generally difficult to degrade biologically, thus requiring suitable processing methods for its removal, so that it can be discharged to the environment safely or even reused orrecycled. One of the challenging processing methods is photocatalytic process. This method is able to utilize abundant resources in the form of sunlight, and is also effective to degrade a wide variety of recalcitrant organic pollutants in the wastewater. This paper presents the current research and development of photocatalytic degradation process for processing of palm oil mill secndary effluent. The review and analysis are focused on synthesis of photocatalyst and the photoreactor design. Based on the results of the literature review and analysis, some recommendations are formulated for future research for their application in advanced POMSE management so that it can be reused for various purposes.
EN
This article describes the design of photo catalyst reactor for oil removing from produced water. Real produced water containing a combination of organic compounds was treated with zinc oxide nanoparticles. In this study, ultraviolet radiations were used to find the efficiency of removing the oil content from the water produced that brought from the Al-Ahdab oilfield in kut/ Iraq by advanced oxidation process (AOP) using (ZnO/UV) in batch system and continuous system. In batch system were studied the effect of zinc oxide concentration (nanoparticles), time of irradiation, and pH. The highest removal rate of oil from the produced water (100%) was obtained during the following optimal conditions: ZnO NPs as catalyst = 55 mg/L, pH =3, at the time of irradiation of 90 minutes in batch experiments. In the continuous system, the effects of flowrate, number of UV-A lamp and time of reaction were studied, the results obtained were the efficiency of decomposition decreases with increasing the flow rate of solution in reactor, the maximum removal efficiency of the process (ZnO/UV) was 80% at 20 mL/min and irradiation time 120 min. In general, zinc oxide is beneficial through its high oil adsorption capacity in addition, It lowers the amount of oil in the produced water.
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