Catalytic oxidation of polymer used in oilfield by bentonite supported Cu(II) complexes in a wide pH range

2021 ◽  
Vol 229 ◽  
pp. 314-321
Author(s):  
Liwa Ma ◽  
◽  
Yuying Xue ◽  
Weichao Du ◽  
Jie Zhang ◽  
...  
Keyword(s):  
Catalytic Oxidation ◽  
Wide Ph Range ◽  
Ph Range

scholarly journals Synthesis of Chitosan-Functionalized Fibrous Membrane for Immobilization of Horseradish Peroxidase: Interfacial Property and Application for Catalytic Oxidation of P-Nitrophenol

2018 ◽  
Vol 13 (2) ◽  
pp. 155892501801300
Author(s):  
Cuie Wang ◽  
Xinhua Liu
Keyword(s):  
Catalytic Oxidation ◽  
Enzyme Catalysis ◽  
Fibrous Membrane ◽  
Interfacial Property ◽  
Mass Loading ◽  
Hydrophobic Polymer ◽  
Immobilization Of Enzymes ◽  
Wide Ph Range ◽  
Ph Range

A hydrophilic fibrous membrane consisting of a network of a non-crystalline hydrophobic polymer and an in situ crosslinked hydrophilic chitosan polymer is studied. This chitosan-functionalized membrane can be employed as a support for immobilization of horseradish peroxidases (HRPs). The immobilized HRPs (mass loading ~110 mg /g) show high stabilities over a wide pH range of 4~10 and temperature range of 25~60°C. In addition, the immobilized HRPs can function as a recyclable biocatalyst for catalytic oxidation of p-nitrophenol (PNP). After 10 cycles, the PNP removal efficiency is 70 percent. The results demonstrate that the chitosan-functionalized fibrous membrane is a promising support for immobilization of enzymes and has applications related to enzyme catalysis.

Cartap wastewater treatment by a microwave-induced catalytic oxidation procedure over Ce/Co/γ-Al2O3

2021 ◽  
Vol 11 (11) ◽  
pp. 1856-1865
Author(s):  
Kaixuan Liu ◽  
Fang Lian ◽  
Guoqi Wang ◽  
Jiaru Dai ◽  
Xuepeng Tian ◽  
...  
Keyword(s):  
Catalytic Oxidation ◽  
Oxidative Degradation ◽  
Degradation Process ◽  
Reaction Rates ◽  
Catalyst Design ◽  
Electron Microscopies ◽  
Transmission Electron ◽  
Wide Ph Range ◽  
Ph Range ◽  
Novel Catalyst

Microwave-assisted catalytic technology is potentially promising in the application of water treatment due to its merits of high reaction rates, simple equipment and operations. In case of the cartap wastewater rarely studied, the easy transformation of cartap into metabolites could induce higher toxicity. This study aimed to develop a novel catalyst Ce/Co/γ-Al2O3 to dispose cartap effectively. The catalyst was prepared by loading Ce and Co on the surface of the support Al2O3, followed by characterization with X-ray diffraction, scanning and transmission electron microscopies. Based on the treatment results, the microwave-induced catalytic oxidation procedure over Ce/Co/γ-Al2O3 could decompose the contaminants efficiently and fast in the case of a low oxidant dosage and a wide pH range. Under the conditions of pH of 5, microwave power of 450 W, catalyst dosage of 0.7 g and hydrogen peroxide dosage of 0.2 mL, the activity of Ce/Co/γ-Al2O3 catalyst could reach up to 86.08%. Importantly, the Ce/Co/γ-Al2O3 catalyst displayed excellent stability after using for 6 times in the degradation process. This work paved a new way for the effective catalyst design for efficient microwave-induced oxidative degradation.

A novel nonheme manganese(ii) complex for (electro) catalytic oxidation of water

2020 ◽  
Vol 4 (6) ◽  
pp. 2656-2660
Author(s):  
Dattaprasad D. Narulkar ◽  
Koteshwar Devulapally ◽  
Anil Kumar U. ◽  
Sunder N. Dhuri ◽  
Vishal M. Dhavale ◽  
...  
Keyword(s):  
Catalytic Oxidation ◽  
Water Oxidation ◽  
Metal Site ◽  
Wide Ph Range ◽  
Ph Range ◽  
Electro Catalytic Oxidation

A nonheme single-metal-site Mn-complex i.e. [Mn(N3Py2)H2O] (ClO4)2; where N3Py2 = N,N′-dimethyl-N-(2-(methyl(pyridin-2-ylmethyl)amino)-ethyl-N′-(pyridin-2-ylmethyl)ethane-1,2-diamine) displays electrochemical water oxidation ability in a wide pH range.

Polarographic and spectrophotometric behaviour of some N-p-phenyl substituted benzamidines

1991 ◽  
Vol 56 (12) ◽  
pp. 2791-2799 ◽  
Author(s):  
Juan A. Squella ◽  
Luis J. Nuñez-Vergara ◽  
Hernan Rodríguez ◽  
Amelia Márquez ◽  
Jose M. Rodríguez-Mellado ◽  
...  
Keyword(s):  
Spectrophotometric Study ◽  
Absorption Bands ◽  
Electrochemical Parameters ◽  
Wide Ph Range ◽  
Group A ◽  
Substituent Constants ◽  
Ph Range ◽  
The Waves

Five N-p-phenyl substituted benzamidines were studied by DC and DP polarography in a wide pH range. Coulometric results show that the overall processes are four-electron reductions. Logarithmic analysis of the waves indicate that the process are irreversible. The influence of the pH on the polarographic parameters was also studied. A UV spectrophotometric study was performed in the pH range 2-13. In basic media some variations in the absorption bands were observed due to the dissociation of the amidine group. A determination of the pK values was made by deconvolution of the spectra. Correlations of both the electrochemical parameters and spectrophotometric pK values with the Hammett substituent constants were obtained.

High degradation efficiency of sulfamethazine with the dual-reaction-center Fe-Mn-SiO2 Fenton-like nanocatalyst in a wide pH range

2021 ◽  
Author(s):  
Manoj Kumar Panjwani ◽  
Qing Wang ◽  
Yueming Ma ◽  
Yuxuan Lin ◽  
Feng Xiao ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Reaction Center ◽  
Degradation Efficiency ◽  
Heterogeneous Fenton ◽  
Wide Ph Range ◽  
Ph Range

The development of a heterogeneous Fenton-like catalyst, possessing high degradation efficiency in a wide pH range, is crucial for wastewater treatment. The Fe-Mn-SiO2 catalyst was designed, and prepared by a...

scholarly journals Defect-Rich Heterogeneous MoS2/rGO/NiS Nanocomposite for Efficient pH-Universal Hydrogen Evolution

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 662 ◽  
Author(s):  
Guangsheng Liu ◽  
Kunyapat Thummavichai ◽  
Xuefeng Lv ◽  
Wenting Chen ◽  
Tingjun Lin ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Hydrogen Evolution ◽  
Hydrogen Evolution Reaction ◽  
Active Sites ◽  
Reduced Graphene ◽  
Heterogeneous Interfaces ◽  
Wide Ph Range ◽  
Ph Range ◽  
A Current ◽  
Poor Stability

Molybdenum disulfide (MoS2) has been universally demonstrated to be an effective electrocatalytic catalyst for hydrogen evolution reaction (HER). However, the low conductivity, few active sites and poor stability of MoS2-based electrocatalysts hinder its hydrogen evolution performance in a wide pH range. The introduction of other metal phases and carbon materials can create rich interfaces and defects to enhance the activity and stability of the catalyst. Herein, a new defect-rich heterogeneous ternary nanocomposite consisted of MoS2, NiS and reduced graphene oxide (rGO) are synthesized using ultrathin αNi(OH)2 nanowires as the nickel source. The MoS2/rGO/NiS-5 of optimal formulation in 0.5 M H2SO4, 1.0 M KOH and 1.0 M PBS only requires 152, 169 and 209 mV of overpotential to achieve a current density of 10 mA cm−2 (denoted as η10), respectively. The excellent HER performance of the MoS2/rGO/NiS-5 electrocatalyst can be ascribed to the synergistic effect of abundant heterogeneous interfaces in MoS2/rGO/NiS, expanded interlayer spacings, and the addition of high conductivity graphene oxide. The method reported here can provide a new idea for catalyst with Ni-Mo heterojunction, pH-universal and inexpensive hydrogen evolution reaction electrocatalyst.

Sign in / Sign up

Export Citation Format

Share Document