Preparation Of Hydrogen Peroxide Research Articles

Kinetic Study of the Acylation Reaction of Dibutylcarbamyl Chloride and Dibutylamine

AbstractTetrabutylurea (TBU) is mainly used as a working liquid in the preparation of hydrogen peroxide via the anthraquinone process. It is reported that dibutylamine (A) reacts with dibutylcarbamyl chloride (B) to produce TBU in the presence of triphosgene, which is the decisive step of the reaction. In this study, we aimed to investigate the reaction kinetics of the decisive step to gain more insight into the reaction. The reaction order as well as the pre-exponential factors (A) and the activation energies (E a) were determined. The kinetic study suggested that the total order of the reaction is second. E a = 5.4 × 104 J/mol, A = 1.5257 × 107 L/(mol × min), calculated through a second-order kinetics model. The accuracy and applicability of the kinetic model were verified by serval experiments, showing that enhancing reaction temperature could shorten the reaction time and increase the conversion rate.

Construction of a novel heteropoly molybdophosphate/graphitized carbon nitride s-scheme heterostructure with enhanced photocatalytic H2O2 evolution activity

The preparation of hydrogen peroxide using a photochemical energy conversion process is a promising green pathway. Herein, a series of graphite-phase carbon nitride/Polyoxometalate (CN-HMoP) composite photocatalysts were prepared by interlayer coordination and segregation strategies. During the synthesis process, the presence of –NH2 or H ions at the CN terminus makes it display a positive charge, which is capable of attracting HMoP with a polyanionic structure. Subsequently, the N atoms on the triazine ring preferentially coordinate with the Mo ions in HMoP to form Mo-N bonds, and the HMoP nanoparticles are able to be inserted layer by layer into the CN nanosheets by interlayer coordination to make the sheet exfoliation, which contributes to the enhancement of the transmission of photogenerated carriers. Notably, the establishment of the S-Scheme heterostructure facilitates the spatial separation of electron-hole pairs and maintains the strongest redox potential. More importantly, under solar/visible light irradiation, the H2O2 generation rate of CN-HMoP reached 137.1 μmol L-1h−1 and 113.1 μmol L-1h−1, which was 17.7 and 16.8 times higher than pristine CN. Therefore, this work can provide guidance for the synthesis of semiconductor photocatalysts for more efficient and green generation of H2O2.

Structurally Disordered Pd−P Nanoparticles as Effective Catalysts for the Production of Hydrogen Peroxide by the Anthraquinone Method

AbstractThe properties of the catalyst based on structurally disordered Pd−P nanoparticles supported on a carbon support (Pd−P/C) in the preparation of hydrogen peroxide by the anthraquinone method have been studied. It is shown that a high yield of H2O2 is observed upon sequential hydrogenation of 2000 mol of eAQ (mol Pd)−1. The H2O2 yield reaches 96 %–97 %. Pd−P nanoparticles are more active in the hydrogenation of 2‐ethyl‐9,10‐anthraquinone than Pd6P crystalline phosphide. In terms of H2O2 yield, Pd−P/C catalysts are superior to known catalysts: Pd/C, Pd/Al2O3. Based on the data of X‐ray powder diffraction, X‐ray photoelectron spectroscopy, Inductively Coupled Plasma and thermogravimetry, the main reasons for the deactivation of Pd−P/C catalysts have been established. Crystallization of the structurally disordered Pd−P nanoparticles, poisoning by eAQ conversion products and leaching of the active component are considered to be possible reasons of the Pd−P/C catalyst deactivation.

Synthesis of Graphene Oxide Frameworks and their Application in Electrocatalytic Preparation of Hydrogen Peroxide

The electrocatalytic performance of graphene oxide frameworks (GOFs) for producing hydrogen peroxide is reported. Three different GOFs are synthesized by interlinking the graphene oxide sheets with different boronic acid deviates through the hydrothermal method and their electrochemical performance are investigated via cyclic voltammetry (CV) and rotating disk electrode (RDE) experiments. Through these electrochemical experiments, we find GOFs favor a 2e-reduction pathway and perform high activity and selectivity in the hydrogen peroxide production process. Taking advantage of these catalysts for the electrochemical synthesis of hydrogen peroxide has the potential to establish a safe, sustainable, and cheap flow-reactor-based production method.

Synthesis and characterization of carbon nanotubes synthesized over NiO/Na-montmorillonite catalyst and application to a hydrogen peroxide sensor

In this study, we demonstrate the synthesis of carbon nanotubes (CNTs) on clay mineral layers, and the preparation of hydrogen peroxide (H2O2) sensor based on CNT/Nafion/Na-montmorillonite (Clay) composite film for the detection of H2O2. The nickel oxide metallic catalyst (NiO) has been prepared by the polyol method and then dispersed onto the clay mineral layers. The CNTs were successfully synthesized over the NiO/Clay catalyst onto clay layers to form a three-dimensional CNT/Clay network by thermal chemical vapor deposition method. From field-emission scanning electron microscope images, the results of X-ray diffraction and Fourier transfer infrared spectra; the layered clay platelets are apparently delaminated and exfoliated after the growth of CNTs onto the surface of clay minerals. The mixed hybrid film of Nafion and CNT/Clay is coated on the glassy carbon electrode to detect hydrogen peroxide (H2O2). This composite film performs a detection limit of 1.0×10−4M for H2O2 and the current is linear for H2O2 concentrations from 0.1 to 12.8mM. Furthermore, the sensitivity of the GCE modified with the CNT/Clay/Nafion hybrid film to H2O2 was calculated to be 1.71×105μAM−1cm−2. Consequently, the CNT/Clay/Nafion medium can probably be a useful electrode for the development of sensors due to its high sensitivity and applicability.

Reactive extraction for preparation of hydrogen peroxide under pressure

The preparation of hydrogen peroxide from anthrahydroquinone by reactive extraction was investigated. The integration process of oxidation of anthrahydroquinone by air and extraction of hydrogen peroxide from the organic phase with water was carried out in a sieve plate column under pressure. The conversion of anthrahydroquinone increased with increasing pressure resulting in an increase of hydrogen peroxide concentration in the aqueous phase. However, no change in extraction efficiency of hydrogen peroxide was observed. A mathematical model for gas-liquid-liquid reactive extraction was established. In themodel, the effects of pressure and gas superficial velocity on reaction were considered.With increasing gas superficial velocity, the conversion of anthrahydroquinone increased, and the fraction of hydrogen peroxide extracted reached a plateau with a maximum of 72.94%. However, both the conversion of anthrahydroquinone and the fraction of hydrogen peroxide extracted decreased with increasing organic phase superficial velocity.

GAS-AGITATED LIQUID AND OXIDATIVE EXTRACTION IN THE ALKYL ANTHRAQUINONE PROCESS FOR THE PREPARATION OF HYDROGEN PEROXIDE

As preliminary investigations on oxidative extraction in the alkyl anthraquinone process for the production of hydrogen peroxide, the air-agitated liquid extraction of hydrogen peroxide from the working solution was studied and the dynamics of the extraction was measured as a function of the oil/water ratio and gas flow rate. The investigations were carried out either in an empty column or in a packed column. The results proved that the use of gas-agitated oxidative liquid extraction was a good way to integrate the oxidative operation unit with the extraction unit in the alkyl anthraquinone process for the preparation of hydrogen peroxide.

Calculation of equlibrium composition in more concentrated systems H2O2-KOH (or NaOH)-H2O

From relations for acid-base equilibria in more concentrated systems H2O2-KOH (or NaOH)-H2O equations were derived for the calculation of the concentrations of OH- and HO2- ions and undissociated H2O2 during preparation of hydrogen peroxide by cathodic reduction of oxygen in alkali hydroxide solution and during spontaneous decomposition of alkaline hydrogen peroxide solutions. Mass changes of the solutions due to the consumption or evolution of gaseous oxygen were taken into account. The role of various parameters is discussed.

Preparation of hydrogen peroxide by cathodic reduction of oxygen in porous electrodes made of different carbonaceous materials

Preparation of hydrogen peroxide by cathodic reduction of oxygen in porous electrodes made of different carbonaceous materials

Preparation of hydrogen peroxide from the peroxides formed on oxidizing propane

AbstractAn investigation is described of the conversion of the peroxide solution, obtained on oxidizing propane, into hydrogen peroxide. The method of doing this is based on the conversion of the said peroxide solution into calcium or barium peroxide by means of calcium or barium hydroxide, which process gives a high yield. Following this conversion, the calcium or barium peroxide is transferred into a dilute hydrogen peroxide solution by means of carbon dioxide, whereas the carbonate is precipitated and filtered off. This conversion, too, proceeds with a high yield.