Copper nickel co-impregnation of Moroccan yellow clay as promising catalysts for the catalytic wet peroxide oxidation of caffeine

Abstract

Copper and nickel were incorporated into the prepared yellow clay (YC) using one of the most widely used methods, for the preparation of heterogeneous catalysts, which is the wet impregnation method (IPM) and its application as a heterogeneous catalyst for Caffeine (CAF). Several catalysts Cooper Nickel's Catalysts (Cu-Ni) were applied to the yellow clay with different weight ratio of Cu and Ni, in order to explore the role of both metals during the catalytic oxidation process CWPO. Furthermore, the CuNi-YC catalysts, were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), Langmuir's surface area, Brunauer Emmett Teller (BET), scanning electron microscope (SEM) and inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES), so as to get a better understanding concerning the catalytic activity's behavior of CuNi-YC catalysts. The optimization of the catalytic activity's effects on the different weight ratios of Cu and Ni, temperature and H 2 O 2 were also examined, using Box-Behnken Response Surface Methodology RSM to enhance the CAF conversion. The analysis of variances (ANOVA) demonstrates that Box-Behnken model was valid and the CAF conversion reached 86.16%, when H 2 O 2 dosage was equal to 0.15 mol.L À1 , copper impregnated (10%) and temperature value attained 60 C. In addition, the regeneration of catalyst's cycles under the optimum conditions, indicated the higher stability up to four cycles without a considerable reduction in its conversion performance.

Preparation and Characterization of CuO/Clay Composite for Methyl Orange Photodegradation

“…This is agreed with the previous study using copper nitrate salt as a CuO catalyst starter compound [24]. In addition, this is may be due to the strong immobilized CuO on the natural clay support [26]. The results obtained are also confirmed by the results of XRD analysis which will be discussed further.…”

Degradation of pollutants in water by Fenton-like oxidation over LaFe-catalysts: Optimization by experimental design

“…𝑋 𝑖 and 𝑋 𝑗 are the coded independent variables and 𝜀 is the random error [21,23]. J o u r n a l P r e -p r o o f 9…”

“…A high performance liquid chromatograph (HPLC), equipped with an isocratic pump (Jasco PU-980 Intelligent HPLC Pump) and a double on-line detection including an UVvis detector (Jasco Intelligent), was used for quantifying Caf at 272 nm, i.e. at the maximum of Caf absorption reported in the literature [21,30,31]. An ion exchange column (Aminex HPX-87H by Biorad) and a mobile phase consisting of 1.8x10 -3 M sulfuric acid with a flow of 0.8 mL/min were used for the separation of reaction products.…”

“…For this study, the experimental reaction conditions were optimized using a J o u r n a l P r e -p r o o f statistical model. The Response Surface Methodology (RSM) is a statistical approach to analyze and reduce the number of experiments to give the optima of independent parameters in the reaction [21,22]. Central composite, Doehlert and Box-Behnken design (BBD) are three classes of response surface designs.…”

Synthesis, characterization, and photocatalytic activities of green sol-gel ZnO nanoparticles using Abelmoschus esculentus and Salvia officinalis: A comparative study versus co-precipitation-synthesized nanoparticles

“…However, these methods come with inherent challenges and limitations during the cleanup process. Issues such as high operational costs, inefficiency at low pollutant concentrations, lack of selectivity, and the potential release of harmful substances into the aquatic environment have been observed [ 14 , 15 ].…”