Hydrogen production from catalytic formic acid ecomposition over Zn based catalysts under room temperature

The depletion of petroleum sources and global warming issues has increased awareness among scientists to produce alternative energy other than the one that we always depend on, which is petroleum. Hydrogen (H2) energy is one of the alternatives that was promising as an efficient and green fuel. Meanwhile, formic acid has been detected as one of the convenient H2 source/storage material. Here, we introduce two heterogeneous catalysts for H2 generation from formic acid. Fe0.1 Zn0.9 and Fe0.5 Zn0.5 were synthesized by a modified microwave method. In this study, we report the result of a detailed study undertaken to investigate the decomposition of formic acid to H2 and carbon dioxide (CO2) using gas chromatography with thermal conductivity detector (GC-TCD). The catalyst used to decompose the formic acid was characterized by x-ray diffraction (XRD) to determine their physicochemical properties. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) were also used to determine the surface morphology and the structure of the synthesized catalysts. The result suggested that in the dehydrogenation reaction, 90-96% of H2 was selectively produced from the formic acid with the presence of FeZn catalyst. For Fe0.1Zn0.9 catalyst, FESEM micrograph shows the particle was well dispersed, existing both away from and close proximity to 50-70 nm in size. Both heterogeneous catalysts are able to produce H2 from formic acid at room temperatures (30°C) with no additives added and with high selectivity

Chemical Reduction Behavior of Zirconia Doped to Nickel at Different Temperature in Carbon Monoxide Atmosphere

The reduction behavior of nickel oxide (NiO) and zirconia (Zr) doped NiO (Zr/NiO) was investigated using temperature programmed reduction (TPR) using carbon monoxide (CO) as a reductant and then characterized using X-ray diffraction (XRD), nitrogen absorption isotherm using BET technique and FESEM-EDX. The reduction characteristics of NiO to Ni were examined up to temperature 700 °C and continued with isothermal reduction by 40 vol. % CO in nitrogen. The studies show that the TPR profile of doped NiO slightly shifts to a higher temperature as compared to the undoped NiO which begins at 387 °C and maximum at 461 °C. The interaction between ZrO2 with Ni leads to this slightly increase by 21 to 56 °C of the reduction temperature. Analysis using XRD confirmed, the increasing percentage of Zr from 5 to 15% speed up the reducibility of NiO to Ni at temperature 550 °C. At this temperature, undoped NiO and 5% Zr/NiO still show some crystallinity present of NiO, but 15% Zr/NiO shows no NiO in crystalline form. Based on the results of physical properties, the surface area for 5% Zr/NiO and 15% Zr/NiO was slightly increased from 6.6 to 16.7 m2/g compared to undoped NiO and for FESEM-EDX, the particles size also increased after doped with Zr on to NiO where 5% Zr/NiO particles were 110 ± 5 nm and 15% Zr/NiO 140 ± 2 nm. This confirmed that the addition of Zr to NiO has a remarkable chemical effect on complete reduction NiO to Ni at low reduction temperature (550 °C). This might be due to the formation of intermetallic between Zr/NiO which have new chemical and physical properties

Oxygenated Hydrocarbons from Catalytic Hydrogenation of Carbon Dioxide

Once fundamental difficulties such as active sites and selectivity are fully resolved, metal-free catalysts such as 3D graphene or carbon nanotubes (CNT) are very cost-effective substitutes for the expensive noble metals used for catalyzing CO2. A viable method for converting environmental wastes into useful energy storage or industrial wealth, and one which also addresses the environmental and energy problems brought on by emissions of CO2, is CO2 hydrogenation into hydrocarbon compounds. The creation of catalytic compounds and knowledge about the reaction mechanisms have received considerable attention. Numerous variables affect the catalytic process, including metal–support interaction, metal particle sizes, and promoters. CO2 hydrogenation into different hydrocarbon compounds like lower olefins, alcoholic composites, long-chain hydrocarbon composites, and fuels, in addition to other categories, have been explained in previous studies. With respect to catalyst design, photocatalytic activity, and the reaction mechanism, recent advances in obtaining oxygenated hydrocarbons from CO2 processing have been made both through experiments and through density functional theory (DFT) simulations. This review highlights the progress made in the use of three-dimensional (3D) nanomaterials and their compounds and methods for their synthesis in the process of hydrogenation of CO2. Recent advances in catalytic performance and the conversion mechanism for CO2 hydrogenation into hydrocarbons that have been made using both experiments and DFT simulations are also discussed. The development of 3D nanomaterials and metal catalysts supported on 3D nanomaterials is important for CO2 conversion because of their stability and the ability to continuously support the catalytic processes, in addition to the ability to reduce CO2 directly and hydrogenate it into oxygenated hydrocarbons

CeO2-Based Heterogeneous Catalysts in Dry Reforming Methane and Steam Reforming Methane: A Short Review

Transitioning to lower carbon energy and environment sustainability requires a reduction in greenhouse gases such as carbon dioxide (CO2) and methane (CH4) that contribute to global warming. One of the most actively studied rare earth metal catalysts is cerium oxide (CeO2) which produces remarkable improvements in catalysts in dry reforming methane. This paper reviews the management of CO2 emissions and the recent advent and trends in bimetallic catalyst development utilizing CeO2 in dry reforming methane (DRM) and steam reforming methane (SRM) from 2015 to 2021 as a way to reduce greenhouse gas emissions. This paper focus on the identification of key trends in catalyst preparation using CeO2 and the effectiveness of the catalysts formulated

CeO₂-Based Heterogeneous Catalysts in Dry Reforming Methane and Steam Reforming Methane: A Short Review

Transitioning to lower carbon energy and environment sustainability requires a reduction in greenhouse gases such as carbon dioxide (CO2) and methane (CH4) that contribute to global warming. One of the most actively studied rare earth metal catalysts is cerium oxide (CeO2) which produces remarkable improvements in catalysts in dry reforming methane. This paper reviews the management of CO2 emissions and the recent advent and trends in bimetallic catalyst development utilizing CeO2 in dry reforming methane (DRM) and steam reforming methane (SRM) from 2015 to 2021 as a way to reduce greenhouse gas emissions. This paper focus on the identification of key trends in catalyst preparation using CeO2 and the effectiveness of the catalysts formulated

Oxygenated Hydrocarbons from Catalytic Hydrogenation of Carbon Dioxide

Once fundamental difficulties such as active sites and selectivity are fully resolved, metal-free catalysts such as 3D graphene or carbon nanotubes (CNT) are very cost-effective substitutes for the expensive noble metals used for catalyzing CO2. A viable method for converting environmental wastes into useful energy storage or industrial wealth, and one which also addresses the environmental and energy problems brought on by emissions of CO2, is CO2 hydrogenation into hydrocarbon compounds. The creation of catalytic compounds and knowledge about the reaction mechanisms have received considerable attention. Numerous variables affect the catalytic process, including metal–support interaction, metal particle sizes, and promoters. CO2 hydrogenation into different hydrocarbon compounds like lower olefins, alcoholic composites, long-chain hydrocarbon composites, and fuels, in addition to other categories, have been explained in previous studies. With respect to catalyst design, photocatalytic activity, and the reaction mechanism, recent advances in obtaining oxygenated hydrocarbons from CO2 processing have been made both through experiments and through density functional theory (DFT) simulations. This review highlights the progress made in the use of three-dimensional (3D) nanomaterials and their compounds and methods for their synthesis in the process of hydrogenation of CO2. Recent advances in catalytic performance and the conversion mechanism for CO2 hydrogenation into hydrocarbons that have been made using both experiments and DFT simulations are also discussed. The development of 3D nanomaterials and metal catalysts supported on 3D nanomaterials is important for CO2 conversion because of their stability and the ability to continuously support the catalytic processes, in addition to the ability to reduce CO2 directly and hydrogenate it into oxygenated hydrocarbons

Inhibition of Mild Steel Corrosion by 4-benzyl-1-(4-oxo-4-phenylbutanoyl)thiosemicarbazide: Gravimetrical, Adsorption and Theoretical Studies

Gravimetric measurements were applied to study the inhibitory effect of 4-benzyl-1-(4-oxo-4-phenylbutanoyl)thiosemicarbazide (BOT) on the corrosion of mild steel in 1.0 M HCl. BOT has a good inhibitory efficacy of 92.5 percent at 500 ppm, according to weight loss results. The effect of inhibitor concentration on the mild corrosion behavior of steel was investigated and it was discovered that the higher the inhibitor concentration, the higher the damping efficiency. The results confirm that BOT is an effective corrosion inhibitor for mild steel in the presence of 1.0 M HCl. Furthermore, the higher protection efficiency with increasing temperature and the free energy value showed that BOT molecules participate in both chemisorption (coordination bonds between the active sites of BOT molecules and d-orbital of iron atoms) and physisorption (through the physical interactions on the mild steel surface). The adsorption mechanism on the mild steel surface obeys the Langmuir adsorption isotherm model. Quantum chemical calculations based on the DFT calculations were conducted on BOT. DFT calculations indicated that the protective efficacy of the tested inhibitor increased with the increase in energy of HOMO. The theoretical findings revealed that the broadly stretched linked functional groups (carbonyl and thionyl) and heteroatoms (sulfur, nitrogen and oxygen) in the structure of tested inhibitor molecules are responsible for the significant inhibitive performance, due to possible bonding with Fe atoms on the mild steel surface by donating electrons to the d-orbitals of Fe atoms. Both experimental and theoretical findings in the current investigation are in excellent harmony

Comparison of different heterogeneous catalysts for the estolides synthesis from oleic acid

Different catalysts, namely various loading of perchloric acid on various supports; HClO 4/silica (SiO 2), HClO 4/silica gel (SG) and HClO 4/alumina (Al 2O 3) were tested for the direct addition reaction of oleic acid (OA) to form estolide compounds. The reactions were carried out under vacuum (2 mBar) for 10 hours at 70 °C under solvent-less conditions. LC-MS ToF of reaction products results showed chromatographic peaks for the presence of two new estolide compounds, oleic-oleic monoestolide acid (m/z 563.51, as [M-H]-), and oleic-oleic diestolide acid (m/z 845.77 [M-H]-). The optimum loading of HClO 4 for every support are 15 wt.% HClO 4/SiO 2 (SiO 215), 10 wt.% HClO 4/SG (SG10) and 35 wt.% HClO 4/Al 2O 3 (Al 2O 335). The SG10 turned out to be the best catalyst, achieving a final conversion of 97.5 % with 79.8 % selectivity to oleic-oleic monoestolide acid and 17.7 % selectivity to oleic-oleic diestolide acid. The activity and selectivity of the SG10 have been investigated and compared with homogeneous HClO 4. The optimum catalysts for every support were characterized by XPS analysis, BET, TEM and TPD-NH 3

The role of tin species in doped iron (III) oxide for photocatalytic degradation of methyl orange dye under UV light

Iron (III) oxide, a stable semiconductor with versatile applications, was synthesized alongside Sn-doped Fe2O3 (Sn–Fe2O3) using the sol-gel technique. Characterization via X-ray diffraction, field-emission scanning electron microscopy, and UV–visible spectroscopy confirmed the presence of α- and γ-Fe2O3 phases in the synthesized powders. Incorporation of the dopant reduced the initial band gap energy of Fe2O3 (2.2 eV) by approximately 0.1 eV. To evaluate photocatalytic performance, Fe2O3 and Sn–Fe2O3 were tested for decolorization efficiency of a methyl orange solution. Results revealed the 5 wt% Sn-doped catalyst as optimal, achieving complete degradation of methyl orange within 120 min under simulated solar light. The addition of small amounts of Sn effectively reduced the Fe2O3 band gap and significantly enhanced photocatalytic performance. Investigation of pH and dye concentration impact on photocatalytic degradation revealed superior activity under acidic conditions compared to alkaline. Furthermore, maintaining a moderate concentration of methyl orange (10 ppm) ensured optimum photocatalytic activity

Nano-Titanium Oxide in Polymeric Contact Lenses: Short Communication

Many individuals suffer from myopia or hyperopia and astigmatism owing to the refractive defects of the eye optics or because of the use of inappropriate contact lenses. This study dealt with three polymers Poly(methyl methacrylate) (PMMA), Poly(Hydroxyl methacrylate) (PHEMA), and Poly(glycidyl methacrylate) (PGMA) and doping them with TiO2 nanoparticles to evaluate the difference between the effect of each lens on the human eye. The TiO2 NPs were prepared in this work by the sol–gel method to obtain 70–90 nm sized particles. Modulation transfer (MTF) and spot diagram were assessed to measure ocular performance. The PGMA-TiO2 contact lens provided the highest image quality at the lowest probability (P) of about p < 0.0001 when inserted on an aberrated eye system because of its ability to eliminate the chromatic aberrations created inside the eyes having a smaller spot size