Decomposition Of Formate Research Articles

Synthesis of Ni and rare earth metal (La, Pr, and Nd) oxides from spent Ni–MH batteries by selective precipitation with formic acid an investigation of photoluminescence properties

A new chemical method was developed for the separation of Ni and rare earths (RE = La, Pr, and Nd) from spent Ni–MH batteries using formic acid as leaching and chelating agent. Ni and RE formates were characterized by FTIR, XRD, TG/DTG, SEM, EDS, and ICP-OES. The photoluminescence properties of RE formate were also investigated. When excited at 420, 421, 422, and 435 nm, RE formate exhibited narrow emission bands at 834, 837, 842, and 867 nm, respectively, attributed to 3H4 → 3P2 transitions of Pr3+ and dominated by the abnormally high intensity of the intraconfigurational transition 1D2 → 1G4. Thermal decomposition of Ni formate resulted in the formation of NiO and PrNiO3. The oxides obtained from RE formate consisted mainly of a crystalline phase of Pr2O3.

High‐Performance RuCl3 Catalyst Systems for Hydro‐Esterification of Methyl Formate and Ethylene

Summary of main observation and conclusionRuCl3 catalyst system has many advantages for the hydro‐esterification of methyl formate and ethylene to methyl propionate. However, the unsatisfied performance restricts the development of this route. In this work, high‐performance RuCl3 catalyst systems (RuCl3‐[PPN]Cl‐Et4NI and RuCl3‐NaI) are firstly reported for this reaction. In RuCl3‐[PPN]Cl‐Et4NI catalyst system, the conversion of methyl formate and the selectivity to methyl propionate are 93.9% and 90.9% at mild reaction conditions (165°C, 2.5 MPa), respectively. Noticeably, a simple inorganic RuCl3‐NaI catalyst system achieves 88.8% conversion of methyl formate and 97.6% selectivity to methyl propionate (86.7% yield) at same conditions. NaI, as a promoter, may inhibit the decomposition of methyl formate and be conducive to the formation of methyl propionate. The effects of solvents and promoters are investigated in detail. In addition, the reaction mechanism has been also analyzed. It is hoped to lay a certain foundation for further industrial application.

Rapid low temperature sintering in air of copper submicron particles with synergistic surface-activation and anti-oxidative protection

The technology to sinter copper inks in air is beneficial for the applications in flexible printed electronics. However, copper based ink could hardly produce conductive copper patterns when sintered in air, because copper is easily oxidized. In this study, a convenient fabrication process for conductive copper films with a simple heat treatment on hotplate in air was successfully developed. The ink was prepared by mixing copper submicron particles with formic acid and an amino-alcohol. The copper oxide on the surface of untreated copper submicron particles was converted to decomposable copper formate. More importantly, the copper submicron particles could be activated by the chemisorbed HCOOH to sinter at low temperatures. 3-Dimethylamino-1,2-propanediol (DMAPD) was introduced to protect copper from oxidation when sintered in air. In addition, DMAPD could promote the decomposition of copper formate by forming copper–amine complex. A resistivity of 54 ± 2 μΩ cm was obtained after sintered at 200 °C for 50 s (63 ± 4 μΩ cm for only 10 s). This simple, convenient and rapid sintering of submicron copper inks in air provides an alternative fabrication method of copper patterns in printed electronics.

Application of nickel nanopowders of different morphology for the synthesis of highly porous materials by powder metallurgy

In this work, we studied the morphology of nickel nanopowders synthesized in various ways: by chemical-metallurgical method, by decomposition of nickel formate and by electroexplosive technology. A comparative analysis of the characteristics of these nanopowders has been carried out. A sample carrier was made from the powder synthesized by electroexplosive technology. A porous material with a gradient structure was created by modifying the pore surface of a sample carrier with catalytically active centers of copper oxide.

Synthesis of Ni nanoparticles with controlled pyrophoricity and mean size

This study establishes that nickel formate decomposition in an argon flow at 209°C and subsequent processing of the obtained nanopowder in a hydrogen flow within a specified time interval, make it possible to control the pyrophoricity and average size of Ni particles.

Catalytic Decomposition of Methyl Formate in the Presence of Transition Metal Complexes, Phosphine Ligands and Water

Catalytic Decomposition of Methyl Formate in the Presence of Transition Metal Complexes, Phosphine Ligands and Water

Unravelling platinum nanoclusters as active sites to lower the catalyst loading for formaldehyde oxidation

Minimizing the use of precious metal remains a challenge in heterogeneous catalysis, such as platinum-based catalysts for formaldehyde oxidation. Here we report the catalyst system Pt/TiO2 with low platinum loading of 0.08 wt%, orders of magnitude lower than conventional catalysts. A volcano-like relationship is identified between reaction rates of formaldehyde and platinum sizes in a scale of single-atoms, nanoclusters and nanoparticles, respectively. Various characterization techniques demonstrate that platinum nanoclusters facilitate more activation of O2 and easier adsorption of HCHO as formates. The activated O facilitates the decomposition of formates to CO2 via a lower reaction barrier. Consequently, this size platinum with such low loading realizes complete elimination of formaldehyde at ambient conditions, outperforming single-atoms and nanoparticles. Moreover, the platinum nanoclusters exhibit a good versatility regardless of supporting on “active” FeOx or “inert” Al2O3 for formaldehyde removal. The identification of the most active species has broad implications to design cost-effective metal catalysts with relatively lower loadings.

Synthesis of Nickel Nanoparticles with Controlled Pyrophoricity and Average Size

The nickel formate decomposition in an argon flow at 209°C with subsequent treatment of the obtained nanopowder in a hydrogen flow for a given time was shown to enable one to control the pyrophoricity and average size of Ni nanoparticles.

Effect of Production Conditions on the Size of Copper Nanoparticles and the Modes of Ignition and Combustion of a Copper Nanopowder in Air

Copper nanoparticles were produced by a chemical metallurgical method and by the thermal decomposition of copper citrate and formate. It was shown that the copper nanopowder obtained from copper citrate is not pyrophoric. Combustion of this copper nanopowder can be initiated by an external source, and the combustion wave velocity is 1.3 ± 0.3 mm/s. The specific surface area (45 ± 5 m2/g) of the copper nanopowder obtained from copper citrate is almost four times as large as that of the nanopowder produced by a chemical metallurgical method. The former nanopowder contains almost no oxides and is stable in atmospheric air, whereas the latter nanopowder is pyrophoric and, therefore, requires passivation, but its passivation gives rise to noticeable amounts of copper oxides. The combustion velocities of the passivated and unpassivated copper nanopowders are almost equal and are 0.3 ± 0.04 mm/s. The dynamics of the temperature fields in ignition and combustion of the copper nanopowders obtained by different methods was studied.

Mechanistic implications of lanthanum-modification on gold-catalyzed formic acid decomposition under SCR-relevant conditions

The use of formate-based ammonia precursors as alternatives to urea in the selective catalytic reduction (SCR) process requires that formic acid released upon their thermolysis in the hot exhaust is rapidly decomposed to carbon dioxide. This work aims at the rational development of a dedicated catalyst that is highly active and selective towards formic acid decomposition to carbon dioxide under SCR-relevant conditions, i.e. under lean conditions and in presence of a large amount of water. The incremental addition of a basic oxide (lanthana) to Au/TiO2 revealed an optimum in the base-induced promotional effect. The base-modification of Au/TiO2 induced a C–H bond weakening of the bidentate formates, which are the dominant surface species and the kinetically relevant intermediates for carbon dioxide formation. At 15 wt% lanthana loading, monodentate formates were substantially suppressed leading to ∼85% reduction in carbon monoxide production. Very high lanthanum surface concentrations lowered the relative coverage of oxygen-derived surface species that are crucial for the decomposition of the abundantly present formates. The linearity of the Constable-Cremer relationship between the apparent activation energy and the natural log of the pre-exponential factor indicates the mechanistic similarity in formic acid decomposition on gold supported on unmodified and lanthanum-modified titania catalysts. Such mechanistic insights helped derive an optimal catalyst. The optimal catalyst exhibited close to three-fold higher activity for ammonium formate decomposition while still maintaining 100% selectivity to ammonia.

Thin Copper Flakes for Conductive Inks Prepared by Decomposition of Copper Formate and Ultrafine Wet Milling

AbstractFabrication of devices by printing conductive interconnections on plastic substrates is of growing interest. Currently, silver flakes are wildly used, however the high cost of silver prevents their wide use in many electrical devices. A new two‐step process for synthesizing thin copper flakes, and their utilization in conductive inks, is reported. In the first step, sub‐micrometer copper particles are formed by thermal decomposition and self‐reduction of copper formate. These copper particles are then milled in a wet bead mill that results in their transformation into thin flakes with an average thickness of 48 nm. X‐ray diffraction results indicate that the copper particles undergo plastic deformation in a mechanism similar to cold rolling. The effect of various process parameters and type of dispersing agents on the morphology and electrical performance is studied. The ink formulations result in printed patterns with 22% of bulk copper conductivity. The optimal ink is used to print functioning near field communication antennas on polyimide film, which is found to have a high bending durability.

Heterogeneous amino-functionalized particles boost hydrogen production from Formic Acid by a ruthenium complex

Silica Amino –Functionalized H2N@SiO2 nanoparticles are shown to boost by >700% the TONs of H2 production by the [Ru/P(CH2CH2PPh2)3] homogeneous catalyst, using Formic Acid (FA) as substrate. Thermodynamic analysis reveals that a significant decrease of the activation energy from Ea = 41±9 kJ/mol to Ea = 28±5 kJ/mol occurs when the H2N@SiO2 solid material is used as cocatlasyt vs. the corresponding propylamine in homogeneous phase. The molecular basis of this thermodynamic mechanism was traced using EPR and variable-Temperature UV–Vis spectroscopy. It is shown that H2N@SiO2 particles play a dual role: [i] they act as cocatalyst, and [ii] they serve as a template which assembles the [Ru/P(CH2CH2PPh2)3] catalyst on its surface, thus promoting rapid formate decomposition via [RuII-hydride] species. Moreover we exemplify, for the first time, that the use of heterogenised H2N@SiO2 cocatalyst alleviates the –so far required-need of excess of amines as additives i.e. a ratio [amine (H2N@SiO2): Ru complex] = [1:1] is adequate to promote high TONs, instead of [50:1] typically needed for liquid amines.

Synthesis of 3,6‐Dihydro‐2H‐[1, 2]‐Oxazines from Nitroarenes and Conjugated Dienes, Catalyzed by Palladium/Phenanthroline Complexes and Employing Phenyl Formate as a CO Surrogate

AbstractPalladium/phenanthroline catalyzed reduction of nitroarenes by in situ‐generated carbon monoxide, from the decomposition of phenyl formate, affords the corresponding nitrosoarenes. The latter are trapped by conjugated dienes to give the corresponding 3,6‐dihydro‐2H‐[1, 2]‐oxazines (hetero Diels‐Alder adducts). Many functional groups are well tolerated. Yields are higher than those obtainable by any previously reported method, including the direct reaction of the diene with the pure nitrosoarene. The reaction can be performed in a single standard glass pressure tube, without the need for autoclaves or high‐pressure CO lines.

Synthesis of α-Alumina Nano-Onions by Thermal Decomposition of Aluminum Formate

A simplified route to prepare α-Al2O3 nano-onions and alumina powders with an excellent surface area through the thermal decomposition of aluminum formate (Al(O2CH)3) precursor is proposed. The calcined powders were characterized by infrared and 13C MAS NMR spectroscopy. Coordination numbers and chemical interactions were determined by 27Al MAS NMR spectroscopy. The 27Al MAS NMR spectra showed the presence of η-Al2O3 at 1000°C, and the transformation to α-Al2O3 at 1100°C. The spectral data also showed that while the precursor contained 6-coordinated aluminum ions, four-, five-, and six-coordinated aluminum species were present after calcination at 400°C. SEM images and BET measurements of α-Al2O3 revealed aggregated particles with a specific surface area of 118 m2/g. A nano-onion structure of α-Al2O3 was evident from the HRTEM image.

Synthesis of supported nickel catalysts in dynamic vacuum using nickel formate as precursor

The innovative method of synthesis of supported nickel catalysts from nickel formate as a precursor is proposed. The conditions of dynamic vacuum allow one to reduce the temperature of nickel formate decomposition, to minimize the agglomeration of metal particles, and to exclude the high-temperature stage of hydrogen reduction. The derived catalysts demonstrate high catalytic activity and are easily regenerated.

Self-Reducible Cu Nanoparticles for Conductive Inks

Copper nanoparticles (Cu NPs) are a potential material for conductive inks because of their low price, high conductivity, and high electromigration resistance. However, Cu NPs are prone to be oxidized in air, which is lethal to conductivity. In this work, we report on the self-reduction of Cu NPs which are synthesized by the thermal decomposition of copper formate (Cuf) using oleylamine (OAM) as the complexing ligand and stabilizing agent. Although the particle surface partially oxidized to Cu2O in air, the cuprous oxide could be reduced to copper during sintering, because of the release of H2 through the decomposition of OAM adsorbed on Cu NPs. This self-reduction ability without the help of additional reduction agent makes the Cu NPs a promising material for conductive inks. The feasibility to formulate conductive ink with the prepared Cu NPs is demonstrated.

Complete oxidation of formaldehyde over TiO2 supported subnanometer Rh catalyst at ambient temperature

Catalytic oxidation of formaldehyde (HCHO) to CO2 and H2O under ambient condition is highly desired for purifying indoor air quality. In this work, it was found for the first time that TiO2 supported subnanometer Rh catalyst exhibited a remarkable activity with complete removal of HCHO at room temperature. The humidity under ambient condition can significantly improve the activity, stability and specific rates but result in lower activation energy for the oxidation of HCHO on this catalyst. A combination of characterizations, such as H2 temperature programmed reduction, adsorption microcalorimetry and in situ diffuse reflectance infrared Fourier transform spectroscopy, demonstrated the importance of Rh species for the dissociative adsorption of O2 and the key role of water on the oxidation of HCHO. The O atoms facilitated the transformation of HCHO adsorbed on TiO2 into intermediate of formates, while the presence of water led to the production of hydroxyl probably from the reaction with the adsorbed O species, which promoted the decomposition of formates to CO2. This study can provide an important implication into the design and fabrication of more economic Rh-based catalysts for ambient HCHO oxidation.

Effect of Carboxylic Acids on Reactive Transfer Printing of Copper Formate Ink

ABSTRACTDuring decomposition of copper formate, a volatile intermediate is formed, that can be utilized to fabricate conductive copper lines for electrical interconnections. By the method called Reactive Transfer Printing (RTP), a pattern of copper (II) formate was printed, and placed adjacent to a second surface; decomposition of the printed pattern led to a transfer of copper to the second substrate. It was found that the yield of the transfer process improved due to presence of several carboxylic acids which are liquid with a high boiling point. Furthermore we found that the transport of copper starts at a lower temperature than previously reported, indicating that the first decomposition step of copper formate is related to the catalytic decomposition of formic acid on a copper surface. The findings enable printing of conductive copper patterns onto the interior surface of a glass vessel.

Thermal decomposition of FC(O)OCH3 and FC(O)OCH2CH3.

The thermal decomposition of methyl and ethyl formates has been extensively studied due to their importance in the oxidation of several fuels, pesticidal properties and their presence in interstellar space. We hitherto present the study of the thermal decomposition of methyl and ethyl fluoroformates, which could help in the elucidation of the reaction mechanisms. The reaction mechanisms were studied using FTIR spectroscopy in the temperature range of 453-733 K in the presence of different pressures of N2 as bath gas. For FC(O)OCH3 two different channels were observed; the unimolecular decomposition which is favored at higher temperatures and has a rate constant kFC(O)OCH3 = (5.3 ± 0.5) × 1015 exp[-(246 ± 10 kJ mol-1/RT)] (in units of s-1) and a bimolecular channel with a rate constant kFC(O)OCH3 = (1.6 ± 0.5) × 1011 exp[-(148 ± 10 kJ mol-1/RT)] (in units of s-1 (mol L)-1). However for ethyl formate, only direct elimination of CO2, HF and ethylene operates. The rate constants of the homogeneous first-order process fit the Arrhenius equation kFC(O)OCH2CH3 = (2.06 ± 0.09) × 1013 exp[-(169 ± 6 kJ mol-1/RT)] (in units of s-1). The difference between the mechanisms of the two fluoroformates relies on the stabilization of a six-centered transition state that only exists for ethyl formate. First principles calculations for the different channels were carried out to understand the dynamics of the decomposition.

Experimental and RRKM Investigations on the Degradation of Ethyl Formate

AbstractA Single pulse shock tube was used to investigate the thermal decomposition of ethyl formate over the temperature range of 909–1258 K and pressure range of 9–17 atm. RRKM (Rice‐Ramsperger‐Kassel‐Marcus) theory was used to estimate the temperature (500–2500 K) and pressure dependent (0.01–100 atm) rate coefficients. The products identified were methane, ethylene, and propane. The initial elementary step for the decomposition of ethyl formate is the unimolecular elimination of ethylene via the reaction CH3CH2OC(O)H → CH2=CH2 + HCOOH. The formed formic acid is further decomposed within the studied temperature range. A detailed reaction mechanism proposed with 21 species and 22 elementary reactions was used to simulate reactant and product distribution over the investigated temperature range. The temperature dependent rate coefficient for the total decomposition of ethyl formate was found to be (909–1258 K)=2.68 × 1011 (s−1) exp (‐42.9 ± 2.2 kcal mol−1/RT). The bond dissociation energies were calculated for the various types of bonds. The calculated total rate coefficient for the thermal decomposition of ethyl formate is (500–2500 K)=3.61 × 1013 (s−1) exp (‐53.4 kcal mol−1/RT) at high pressure limit.