scholarly journals Bimetallic Cu/Fe Catalysts for Ibuprofen Mineralization

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1383
Author(s):  
Sajid Hussain ◽  
Eleonora Aneggi ◽  
Daniele Goi ◽  
Alessandro Trovarelli

At present, the use of conventional wastewater processes is becoming increasingly challenging, mainly due to the presence of biorecalcitrant organic matter. Advanced oxidation processes such as Fenton, Fenton-like and hybrid processes have been successfully employed for the treatment of highly concentrated and toxic non-biodegradable pollutants. Here, a series of bimetallic catalysts, based on Cu/Fe supported over ZrO2, were investigated for the mineralization of ibuprofen with a heterogeneous Fenton-like reaction. The materials were prepared by incipient wetness impregnation and characterized by standard techniques. Temperature-programmed experiments highlighted the promotion of the reduction in CuO due to the synergistic effects of the coupled redox cycles of copper (Cu2+/Cu+) and iron (Fe+3/Fe+2). 5%Cu-5%Fe/ZrO2 not only displays the highest ibuprofen mineralization (83%) under optimum conditions but also exploits its activity in a wider range of pH (3–5) with extremely low metal leaching. The recycling of bimetallic catalysts reveals that only the 5%Cu-5%Fe/ZrO2 system is able to provide sustainable activity in heterogeneous Fenton process.

2019 ◽  
Vol 45 ◽  
pp. 146867831987032
Author(s):  
Zhang Jiaying

A series of Ni–Fe/MCM-41 bimetallic catalysts and also Ni/MCM-41 and Fe/MCM-41 catalysts were prepared by the incipient-wetness impregnation method and tested for their activity for CO methanation in a continuous-flow microreactor. The results showed that the catalytic activities of the Ni–Fe/MCM-41 bimetallic catalysts were much higher than those of the Ni/MCM-41 and Fe/MCM-41 catalysts at low temperatures (200°C–325°C). The 10%Ni–5%Fe/MCM-41 catalyst showed the best activity with a CO conversion of almost 100% and a CH4 selectivity of 98% at 350°C under a pressure of 1.5 MPa with a 3:1 molar ratio of H2 to CO and a weight hourly space velocity of 12,000 mL h−1 g−1. The catalysts were characterized by N2 physisorption measurements, X-ray diffraction, and H2-temperature-programmed reduction. The results showed that the addition of Fe will lead to the formation of finer Ni particles and Ni–Fe alloy, which were the main reasons for the activity increase in the Ni–Fe/MCM-41 catalysts.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 54
Author(s):  
Yu-Ming Chu ◽  
Hafiz Muhammad Asif Javed ◽  
Muhammad Awais ◽  
Muhammad Ijaz Khan ◽  
Sana Shafqat ◽  
...  

The photocatalytic pretreatment of lignocellulosic biomass to oxidize lignin and increase biomass stability has gained attention during the last few years. Conventional pretreatment methods are limited by the fact that they are expensive, non-renewable and contaminate the anaerobic digestate later on. The present study was focused to develop a metal-derived photocatalyst that can work with visible electromagnetic spectra light and oxidize commercial lignin liquor. During this project the advanced photocatalytic oxidation of lignin was achieved by using a quartz cube tungsten T3 Halogen 100 W lamp with a laboratory manufactured TiO2-ZnO nanoparticle (nanocomposite) in a self-designed apparatus. The products of lignin oxidation were confirmed to be vanillic acid (9.71 ± 0.23 mg/L), ferrulic acid (7.34 ± 0.16 mg/L), benzoic acid (6.12 ± 0.17 mg/L) and p-coumaric acid (3.80 ± 0.13 mg/L). These all products corresponded to 85% of the lignin oxidation products that were detectable, which is significantly more than any previously reported lignin pretreatment with even more intensity. Furthermore, all the pretreatment samples were supplemented in the form of feedstock diluent in uniformly operating continuously stirred tank reactors (CSTRs). The results of pretreatment revealed 85% lignin oxidation and later on these products did not hinder the CSTR performance at any stage. Moreover, the synergistic effects of pretreated lignin diluent were seen that resulted in 39% significant increase in the methane yield of the CSTR with constant operation. Finally, the visible light and nanoparticles alone could not pretreat lignin and when used as diluent, halted and reduced the methane yield by 37% during 4th HRT.


Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 553
Author(s):  
Mansurbek Urol ugli Abdullaev ◽  
Sungjune Lee ◽  
Tae-Wan Kim ◽  
Chul-Ung Kim

Among the zeolitic catalysts for the ethylene-to-propylene (ETP) reaction, the SSZ-13 zeolite shows the highest catalytic activity based on both its suitable pore architecture and tunable acidity. In this study, in order to improve the propylene selectivity further, the surface of the SSZ-13 zeolite was modified with various amounts of tungsten oxide ranging from 1 wt% to 15 wt% via a simple incipient wetness impregnation method. The prepared catalysts were characterized with several analysis techniques, specifically, powder X-ray diffraction (PXRD), Raman spectroscopy, temperature-programmed reduction of hydrogen (H2-TPR), temperature-programmed desorption of ammonia (NH3-TPD), inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and N2 sorption, and their catalytic activities were investigated in a fixed-bed reactor system. The tungsten oxide-modified SSZ-13 catalysts demonstrated significantly improved propylene selectivity and yield compared to the parent H-SSZ-13 catalyst. For the tungsten oxide loading, 10 wt% loading showed the highest propylene yield of 64.9 wt%, which was 6.5 wt% higher than the pristine H-SSZ-13 catalyst. This can be related to not only the milder and decreased strong acid sites but also the diffusion restriction of bulky byproducts, as supported by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDS) observation.


2010 ◽  
Vol 10 (1) ◽  
pp. 1-6 ◽  
Author(s):  
R. Murillo ◽  
J. Sarasa ◽  
M. Lanao ◽  
J. L. Ovelleiro

The degradation of chlorpyriphos by different advanced oxidation processes such as photo-Fenton, TiO2, TiO2/H2O2, O3 and O3/H2O2 was investigated. The photo-Fenton and TiO2 processes were optimized using a solar chamber as light source. The optimum dosages of the photo-Fenton treatment were: [H2O2]=0.01 M; [Fe3 + ]=10 mg l−1; initial pH = 3.5. With these optimum conditions total degradation was observed after 15 minutes of reaction time. The application of sunlight was also efficient as total degradation was achieved after 60 minutes. The optimum dosage using only TiO2 as catalyst was 1,000 mg l−1, obtaining the maximum degradation at 20 minutes of reaction time. On the other hand, the addition of 0.02 M of H2O2 to a lower dosage of TiO2 (10 mg l−1) provides the same degradation. The ozonation treatment achieved complete degradation at 30 minutes of reaction time. On the other hand, it was observed that the degradation was faster by adding H2O2 (H2O2/O3 molar ratio = 0.5). In this case, total degradation was observed after 20 minutes.


Author(s):  
Gülin Ersöz ◽  
Süheyda Atalay

AbstractOne of the advanced oxidation processes, the Oxone process, was studied to determine its effects on the decolorization of Reactive Black 5 (RB5) in an aqueous solution. Ferrous ion was chosen as the transition metal due to its potential catalytic effect and wide availability in dye containing industrial effluents. The effects of the operating parameters such as Fe(II) and Oxone concentration, initial pH, and temperature on the process performance were investigated. The optimum conditions were determined as: 0.5 mM of Oxone concentration, 0.5 mM of Fe


2018 ◽  
Vol 78 (5) ◽  
pp. 1159-1167 ◽  
Author(s):  
Behnam Heidari ◽  
Mohsen Soleimani ◽  
Nourollah Mirghaffari

Abstract The Fenton process is a useful and inexpensive type of advanced oxidation process for industrial wastewater treatment. This study was performed with the aim of using the steel slag as a catalyst in the heterogeneous Fenton process in order to reduce the chemical oxygen demand (COD) of oil refinery wastewater. The effects of various parameters including the reaction time (0.5, 1.0, 2.0, 3.0 and 4.0 h), pH (2.0, 3.0, 4.0, 5.0, 6.0 and 7.0), the concentration of steel slag (12.5, 25.0 and 37.5 g/L), and H2O2 concentration (100, 250, 400 and 500 mg/L) on the Fenton process were investigated. Furthermore, the effect of microwave irradiation on the process efficiency was studied by considering the optimum conditions of the mentioned parameters. The results showed that using 25.0 g/L of steel slag and 250 mg/L H2O2, at pH = 3.0, could reduce COD by up to 64% after 2.0 h. Also, microwave irradiation decreased the time of the process from 120 min to 25 min in the optimum conditions, but it consumed a high amount of energy. It could be concluded that steel slags had a high potential in the treatment of oil refinery wastewater through the Fenton process.


2019 ◽  
Vol 79 (12) ◽  
pp. 2357-2365 ◽  
Author(s):  
Huaisu Guo ◽  
Weilin Guo ◽  
Yang Liu ◽  
Xiaohua Ren

Abstract In this work, quinone-modified metal-organic framework MIL-101(Fe)(Q-MIL-101(Fe)), as a novel heterogeneous Fenton-like catalyst, was synthesized for the activation of persulfate (PS) to remove bisphenol A (BPA). The synthetic Q-MIL-101(Fe) was characterized via X-ray diffraction, scanning electron microscope, Fourier transform infrared, electrochemical impedance spectroscopy, cyclic voltammetry and X-ray photoelectron spectroscopy. As compared to the pure MIL-101(Fe), Q-MIL-101(Fe) displayed better catalytic activity and reusability. The results manifested that the Q-MIL-101(Fe) kept quinone units, which successfully promoted the redox cycling of Fe3+/Fe2+ and enhanced the removal efficiency. In addition, the reaction factors of Q-MIL-101(Fe) were studied (e.g. pH, catalyst dosage, PS concentration and temperature), showing that the optimum conditions were [catalyst] = 0.2 g/L, [BPA] = 60 mg/L, [PS] = 4 mmol/L, pH = 6.79, temperature = 25 °C. On the basis of these findings, the probable mechanism on the heterogeneous activation of PS by Q-MIL-101(Fe) was proposed.


Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2909 ◽  
Author(s):  
Xiaofan Lv ◽  
Yiyang Ma ◽  
Yangyang Li ◽  
Qi Yang

Fe0@Fe3O4 nanoparticles with dispersibility and stability better than single nano zero-valent iron (nZVI) were synthesized and combined with hydrogen peroxide to constitute a heterogeneous Fenton-like system, which was creatively applied in the degradation of 2,4-dichlorophenoxyacetic acid (2,4-D). The effects of different reaction conditions like pH, hydrogen peroxide concentration, temperature, and catalyst dosage on the removal of 2,4-D were evaluated. The target pollutant was completely removed in 90min; nearly 66% of them could be mineralized, and the main intermediate product was 2,4-dichlorophenol. Synergistic effects between nZVI and Fe3O4 made the 2,4-D degradation efficiency in the Fe0@Fe3O4/H2O2 system greater than in either of them alone. More than a supporter, Fe3O4 could facilitate the degradation process by releasing ferrous and ferric ions from the inner structure. The reduction of 2,4-D was mainly attributed to hydroxyl radicals including surface-bound ∙OH and free ∙OH in solution and was dominated by the former. The possible mechanism of this Fe0@Fe3O4 activated Fenton-like system was proposed.


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