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Phenylacetaldehyde (PhA) is an aromatic aldehyde which has a hyacinth‐like floral, sweet and green‐leafy odour. PhA is used as a perfumery chemical and a rate‐controlling additive in cosmeceutical and polymer industries, respectively. The conventional process of PhA manufacturing in industries involve hazardous and costly feedstock and often lead to generation of substantial amount of waste. Moreover, usage of stoichiometric reagents often makes the processes economically impractical. This article illustrates the possibility of production of PhA from low‐cost feedstock styrene through a single‐step, one‐pot method wherein various metal oxides have been utilized as catalysts for styrene oxidation under the influence of cumene hydroperoxide (CHP). Ag2O is found to be the highest PhA‐yielding catalyst and a promising candidate for scaling up for its considerably good reusability up to 6 consecutive uses. A maximum of ~45% PhA selectivity has been observed at ~60% styrene conversion. Interestingly, this process does not require any alkaline/acid wash and hence does not produce any organic/inorganic liquid effluent stream. Furthermore, all the major byproducts found, that is styrene oxide, benzaldehyde and acetophenone, are themselves considered as valorized styrene derivatives. Overall, the metal oxide catalysed styrene oxidation has potential to take over the conventional industrial process(es) for sustainable selective production of PhA Along with a plausible mechanism of styrene oxidation over Ag2O, a conceptualized reaction–separation framework has been reported for intensified production of PhA from CHP‐based styrene oxidation. [ABSTRACT FROM AUTHOR]

This work first proposes a rigorous process model for the industrial production of cumene hydroperoxide (CHP) through cumene oxidation. The research scope covers process design, optimization, and controllability studies. The study began with a comprehensive analysis and supplementation of the required physical properties. The group contribution method or COSMO-based calculations are used to estimate the required mixture properties. With a detailed description of the thermodynamics, the kinetic parameters are re-regressed using the literature data. Subsequently, alternative configurations of the process are designed and compared, including the single-reactor (1R) and three-reactor (3R) designs. After thorough analysis, it is found that employing a 3R-design increases per-pass conversion by 4.8 % and CHP yield by 4.0 %, while reducing reboiler duty by 20.5 % compared to the single-reactor process. Finally, alternative control structures are proposed for the 3R-design. The control strategy employing pressure scheduling in the reactors and controlling the bottom temperature of the stripper (i.e. CS3) is found to be effective in rejecting the specified feed disturbances (i.e. ± 10 % flowrate change and 2 % impurity of CHP, acetone, phenol, and water in the cumene feed, respectively). • Design, optimization, and control of the cumene oxidation process are studied. • The 3 R design leads to an increased conversion and product yield. • The 3 R design significantly saves the energy required for separation. • Pressure scheduling of the reactors help to achieve effective control performances. • Controlling the stripper bottom temperature reduces the deviation of product purity. [ABSTRACT FROM AUTHOR]

A kinetic modeling was carried out for the synthesis of cumene hydroperoxide (an initiator of curing for acrylic adhesives) based on cumene oxidation in the presence of Mg, Ca, Sr, or Ba 2-ethylhexanoate as a catalyst. The kinetic model includes the formation reactions of intermediate components of the reaction mixture–catalyst adducts, the initiation reactions, the propagation and chain termination reactions, and molecular reactions characterizing both noncatalytic and catalytic cumene oxidation, as well as specific reactions caused by the catalytic properties of 2-ethylhexanoates of nontransition metals. The kinetic model reproduces the concentrations of reaction mixture components depending on time within the experimental data error, which confirms the kinetic scheme included in the model. [ABSTRACT FROM AUTHOR]

Kinetic simulation of cumene oxidation leading to the obtaining of cumene hydroperoxide (the curing initiator for acrylic adhesives) in the presence of a Ca, Sr, Ba chloride complex with dibenzo-18-crown-6 ether as a catalyst is performed. The kinetic model involves a mechanism for the formation of intermediate adducts between reaction mixture components and the catalyst, initiation reactions, the reactions of chain propagation and chain termination, and molecular reactions inherent in cumene oxidation with no catalyst and in the presence of a homogeneous catalyst, as well as specific reactions caused by the chemical features of crown ethers. The model is shown to reflect the experimental time dependences for the cumene hydroperoxide concentration to a complete extent and time dependences for the concentrations of by-products at a qualitative level (the calculated curves reproduce the shapes of the experimental curves). This indicates that, on the whole, the mechanism used for to construct the model is quite correct. [ABSTRACT FROM AUTHOR]

To accurately evaluate the thermal hazards of cumene hydroperoxide (CHP) under heterogeneous temperature systems, a pressure vessel test device was employed to analyze the decomposition behavior of CHP in the heterogeneous temperature vessel. The influences of furnace temperature (200°C–300 °C) and sample mass (1 g–5 g) on the decomposition behavior were discussed respectively. The results show that in the 10 groups of experiments, CHP begins to accelerate autocatalytically after a long period of initiation step, with a rapid increase in temperature and pressure, and reach the maximum temperature and pressure rise rates in the later period. The maximum temperature and pressure are 248.39 °C and 324.1 kPa, and the maximum temperature and pressure rise rates reach 8.477 °C/s and 71.6 kPa/s, respectively. At a sample mass of 3 g, with the increase of furnace temperature, the maximum temperature and temperature rise rate increase, while both the maximum pressure and pressure rise rate are close; the thermal decomposition reaction time decreases exponentially, which obeys an equation of Δtd=2.592×107exp(−Te/18.051)+184.325(200°C≤Te≤300°C). At a furnace temperature of 300 °C, the maximum values of temperature, temperature rise rate, pressure, and pressure rise rate all increase with increasing sample mass.

Organic peroxides, due to temperature manipulation failure and/or manner disturbances, had been probable to lead to the prevalence of runaway phenomena, even fire, and explosion. Cumene hydroperoxide (CHP), is a traditional liquid organic peroxide for industrial purposes and is applied as a free radical initiator for polymerization reactions in the petrochemical industry. Its utilization in the industrial processes had certain potential safety hazards. In this work, linearly ramped thermal decomposition in CHP was performed using differential scanning calorimetry under a nitrogen atmosphere. Kinetic analysis is made using data from the ramped measurements with two integral strategies (Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose). The gaseous products of thermal decomposition in CHP are investigated via thermal gravimetric evaluation coupled with Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry. Combined with the experimental results, the possible decomposition path of CHP is discussed. This makes up the gap of unclear decomposition mechanism of CHP in inert atmosphere, and has important reference significance for its industrial production and application. [Display omitted] [ABSTRACT FROM AUTHOR]

The kinetics of cumene oxidation in the presence of Mg, Ca, Sr, Ba 2-ethylhexanoates is studied experimentally. It is established that the Mg 2-ethylhexanoate exhibits the highest catalytic performance. It is shown by the PBEPBE-GD3/def2TZVP method that the intermediate adducts of cumene, cumene hydroperoxide (gauche- and trans-conformers), and dimethyl phenyl carbinol with Mg 2-ethylhexanoate are thermodynamically possible. The data on the structure of intermediate adducts and electron density distribution were obtained by conducting PBEPBE-GD3/def2TZVP quantum chemical calculations. The totality of structural data, energy parameters of the adducts, nature of the electron density distribution, and the strength of the O–O bond show that the intermediate adduct of cumene hydroperoxide (trans-conformer) with Mg 2-ethylhexanoate most rapidly decomposes into free radicals. A mechanism of catalytic activity of Mg 2-ethylhexanoate in cumene oxidation is proposed based on the results of quantum chemical simulation. [ABSTRACT FROM AUTHOR]

Hydroxybenzene, commonly known as phenol, is one of the most important organic commodity chemicals. To produce phenol, the cumene process is the most used process worldwide. A crucial step in this process is the Hock rearrangement, which has a major impact on the overall cumene consumption rate and determines the safety level of the process. The most used catalyst for the cleavage of cumene hydroperoxide (CHP) is sulfuric acid. Besides its strong corrosive property, which increases plant investment costs, it also requires neutralization after the decomposition step to prevent side reactions. In this study, we show that high-temperature-treated Linde Type X (LTX) zeolites exhibit a high activity for the peroxide cleavage step. In addition, the structure–activity relationship responsible for this good performance in the reaction system of the HOCK rearrangement was investigated. XRPD analyses revealed the formation of a new phase after temperature treatment above 900 °C. The Si/Al ratio determined by EDX suggested the formation of extra-framework aluminum, which was confirmed by solid-state NMR analysis. The newly formed extra-framework aluminum was found to be responsible for the high catalytic activity. BET analyses showed that the surface area drops at higher calcination temperatures. This leads to a lower catalytic activity for most known reactions. However, for this study, no decrease in activity has been observed. The newfound material shows extraordinarily high activity as a catalyst in the HOCK cleavage and has the potential to be a heterogeneous alternative to sulfuric acid for this reaction. [ABSTRACT FROM AUTHOR]

Cu-doped calcium aluminum hydrotalcites of Ca4CuxAl-LDHs（x=0，0. 1，0. 3，0. 5，0. 8，1. 0） were prepared by a coprecipitation method，and its catalytic activity for liquid phase oxidation of cumene to cumene hydroperoxide（CHP） was investigated. Ca4CuxAl-LDHs were characterized by X-ray diffraction， Fourier transform infrared spectroscopy，scanning electron microscope and thermal analysis. The prepared Ca4CuxAl-LDHs remain the layered structure of hydrotalcite. The copper doping results in a smaller pore size and a larger specific surface area. When the feed ratio（catalyst/cumene） is 7. 5 mg/mL，the reaction temperature is 85 ℃，the flow rate of oxygen is 15 mL/min，and the reaction time is 7 h，Ca4Cu0. 5Al-LDHs shows excellent catalytic activity，the conversion of cumene is 34. 5% and the selectivity of CHP is 86. 9%. After being used for five cycles，the conversion of cumene is 31. 2% and the selectivity of CHP is 83. 3%. The study is useful for developing the production method for cumene hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Runaway reactions of organic peroxides (OPs) are a significant issue in process safety, due to their fragile bonds and extensive heat release during abnormal conditions. As one of the typical OPs and an intermediate in the process of producing phenol, cumene hydroperoxide (CHP) is likely to mix with its products and lead to an uncontrollable self‐accelerating decomposition reaction. In this study, the thermal hazard of CHP mixed with four products separately was evaluated and identified using accelerating rate calorimeter technology. Experimental data illustrated that the maximum pressure rise rate had greatly increased from 1.1 to 15.5, 18.3, and 41.5 bar min−1, and the maximum self‐heating rate had dreadfully raised from 5.4 to 107.7, 116.9, and 231.0°C min−1, when CHP mixed with its products from methanol to phenol, acetophenone, or dimethylphenyl carbinol, respectively. These phenomena indicated a precarious and dangerous reaction decomposition mechanism of CHP after its products mixed under runaway conditions. This work is expected to help researchers and even industrial workers to better identify the potential thermal hazard of CHP in the presence of products; in particular, experimental and calculated parameters are necessary for the appropriate choice of safe conditions of application, waste disposal, storage, and transportation of CHP. [ABSTRACT FROM AUTHOR]

Ti-containing Mobil composition of matter-twenty-two (Ti-MWW) zeolite was prepared via a two-step post-synthesis process and then characterized by X-ray fluorescence, nitrogen adsorption-desorption isotherms, Fourier transform infrared absorption spectra, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectra. These results indicate that the textural properties of MWW were well preserved after acid treatment and incorporation of titanium. An adsorptive-oxidative desulfurization (AODS) system was successfully developed on the basis of a model oil containing dibenzothiophene (DBT) with the as-prepared Ti-MWW being the catalyst and adsorbent and cumene hydroperoxide (CHP) being the oxidant. The parameters influencing the desulfurization performance were systematically investigated. These parameters include the Ti-MWW dosage, the reaction temperature, the stirring speed, the molar ratio of CHP to DBT and the additions of olefins and aromatics to the system. The conversion rate of DBT reached 99.6% via the catalytic oxidation process and the turnover frequency was 40.1 h−1. Meanwhile, the oxidation products of DBT were removed by Ti-MWW adsorption. The recycling and regeneration performance of Ti-MWW were also investigated, and the DBT conversion reached 99.5% using the regenerated Ti-MWW. This work provides useful information for the construction of solvent-free oxidative desulfurization systems using a zeolite. [ABSTRACT FROM AUTHOR]

In the present work, the role of the carboxyl group of o-dihydroxybenzoic acids (pyrocatechuic, 2,3-diOH-BA and protocatechuic, 3,4-diOH-BA) on the protection against induced oxidative stress in Saccharomyces cerevisiae was examined. Catechol (3,4-diOH-B) was included for comparison. Cell survival, antioxidant enzyme activities, and TBARS level were used to evaluate the efficiency upon the stress induced by H2O2 or cumene hydroperoxide. Theoretical calculation of atomic charge values, dipole moment, and a set of indices relevant to the redox properties of the compounds was also carried out in the liquid phase (water). Irrespective of the oxidant used, 2,3-diOH-BA required by far the lowest concentration (3–5 µM) to facilitate cell survival. The two acids did not activate catalase but reduced superoxide dismutase activity (3,4-diOH-BA>2,3-diOH-BA). TBARS assay showed an antioxidant effect only when H2O2 was used; equal activity for the two acids and inferior to that of 3,4-diOH B. Overall, theoretical and experimental findings suggest that the 2,3-diOH-BA high activity should be governed by metal chelation. In the case of 3,4-diOH BA, radical scavenging increases, and chelation capacity decreases. The lack of carboxyl moiety (3,4-diOH B) improves to radical scavenging, interaction with lipophilic free radicals, and antioxidant enzymes. The present study adds to our knowledge of the antioxidant mechanism of dietary phenols in biological systems. [ABSTRACT FROM AUTHOR]

The marine foodborne enteropathogen Vibrio parahaemolyticus contains the chief organic peroxide reductases AphC1-AhpC2 and a putative organic hydroperoxide resistance enzyme (Ohr; VPA1681) against different peroxides. This study investigated the function of the Ohr under the presence of AhpC1-AhpC2 in this pathogen by gene mutation. Experimental results demonstrated that the ohr gene product was a weak scavenger of H2O2 only in the mutant strains that lacked the peroxide sensor/regulator oxyR and ahpC1-ahpC2 genes. The Ohr of V. parahaemolyticus was highly effective at scavenging organic peroxide, as demonstrated by assaying the defective changes in the Δohr mutant strain and determining the detoxifying activity of the purified recombinant V. parahaemolyticus Ohrvp protein in the reduced form. The Ohr and ΔhpC1-ΔhpC2 exhibited similar functions against organic peroxides; however, only the DahpC1 DahpC2 mutant strain showed a significant increase in susceptibility to several disinfectants, organic acids, and antibiotics compared with the wild-type strain. The transcription of the ohr gene depended on exogenous cumene hydroperoxide (cumene) stress and was markedly enhanced in the ΔohrR (VPA1682) mutant strains. This study revealed the organic hydroperoxide reductase activity of the Ohr in V. parahaemolyticus, and its role probably depends on sophisticated regulation by OhrR. IMPORTANCE Vibrio parahaemolyticus is the most prevalent foodborne pathogen in Taiwan and some other coastal Asian countries, and its antioxidative activity contributes to the tolerance of this bacterium to different environmental stresses. This study reports on the function of the organic hydroperoxide resistance gene (ohr; VPA1681) and its gene regulator, ohrR (VPA1682), in this pathogen. The strain with the ohr gene had effective protection against organic peroxide, and the recombinant Ohrvp was active in its reduced form. The function of Ohr was significant mostly in strains in which the function of AhpC1-AhpC2 was limited. The ohrR repressor of the ohr gene was effective at low concentrations of organic peroxide. Other common Vibrio species that contain homologous ohr, ohrR, ahpC1, and ahpC2 genes, which are phylogenetically close to those of V. parahaemolyticus, may share similar functions to those revealed in this study. [ABSTRACT FROM AUTHOR]

Hydroxybenzene, commonly known as phenol, is one of the most important organic commodity chemicals. To produce phenol, the cumene process is the most used process worldwide. A crucial step in this process is the Hock rearrangement, which has a major impact on the overall cumene consumption rate and determines the safety level of the process. The most used catalyst for the cleavage of cumene hydroperoxide (CHP) is sulfuric acid. Besides its strong corrosive property, which increases plant investment costs, it also requires neutralization after the decomposition step to prevent side reactions. In this study, we show that high-temperature-treated Linde Type X (LTX) zeolites exhibit a high activity for the peroxide cleavage step. In addition, the structure–activity relationship responsible for this good performance in the reaction system of the HOCK rearrangement was investigated. XRPD analyses revealed the formation of a new phase after temperature treatment above 900 °C. The Si/Al ratio determined by EDX suggested the formation of extra-framework aluminum, which was confirmed by solid-state NMR analysis. The newly formed extra-framework aluminum was found to be responsible for the high catalytic activity. BET analyses showed that the surface area drops at higher calcination temperatures. This leads to a lower catalytic activity for most known reactions. However, for this study, no decrease in activity has been observed. The newfound material shows extraordinarily high activity as a catalyst in the HOCK cleavage and has the potential to be a heterogeneous alternative to sulfuric acid for this reaction.

Hole transport layer is one of the primary factors that improve the optical-electric properties of perovskite solar cells. Spiro-OMeTAD is frequently utilized as hole transport materials in PSCs. However, pristine or oxygen oxidized spiro-OMeTAD has low mobility and conductivity. Herein, cumene hydroperoxide is introduced to accelerate the oxidation of spiro-OMeTAD, which improves the carrier mobility, declines the trap-state density and optimizes the energy match with perovskite layer, leading to the enhancement of the performance of device. Kelvin probe force microscopy images and Atomic force microscopy images show the improvement of interface morphology. Multiple electrochemical characterizations demonstrate the acceleration of spiro-OMeTAD oxidation, the enhancement of conductivity of the doped hole transport material, and the decline of trap-state density and carrier annihilation in hole transport layer/perovskite interface after the modification. The perovskite solar cell doped with optimal concentration acquires a power conversion efficiency of 20.33%, while the undoped device gets an efficiency of 18.00%.

The management of reactivity hazards has long been a problem in chemical process and the indexing approach is believed to be an effective solution. However, while most of the reactivity indexes do not consider the runaway scenario and are often quite rough, the assessment criteria used to judge thermal runaway does not take the type of scenario or the severity of the consequences into account. At present, there are no index system that can represent the reactivity hazards in chemical process comprehensively. Therefore, this paper has developed a hazard index for reactivity management (HIRM) in chemical processes. The reactivity hazards could be identified, evaluated and managed through nine steps defined by this method. The HIRM method is able to assess various runaway scenarios and quantify the reactivity hazards based on the consequence and probability. The consequence is rated by the damage radius which represents the damage level caused by fire, explosion, and toxic release due to reaction runaway. The probability indicates the initial event frequency, the initiation time and the controllability of the entire runaway process. The reactivity risks could then be classified by the HIRM index uniformly and comprehensively, with methods to manage the risks proposed. Six sets of equipment in the dicumyl peroxide (DCP) production unit was used as an example to demonstrate the construction of the HIRM index system. The results showed good agreement with the actual risk distribution, meaning that the HIRM method is an effective tool for the management of reactivity hazards in chemical process. [ABSTRACT FROM AUTHOR]

The oxidation of cumene and following cleavage of cumene hydroperoxide (CHP) with sulfuric acid (Hock rearrangement) is still, by far, the dominant synthetic route to produce phenol. In 2020, the global phenol market reached a value of 23.3 billion US$ with a projected compound annual growth rate of 3.4% for 2020–2025. From ecological and economical viewpoints, the key step of this process is the cleavage of CHP. One sought-after way to likewise reduce energy consumption and waste production of the process is to substitute sulfuric acid with heterogeneous catalysts. Different types of zeolites, silicon-based clays, heteropoly acids, and ion exchange resins have been investigated and tested in various studies. For every type of these solid acid catalysts, several materials were found that show high yield and selectivity to phenol. In this mini-review, first a brief introduction and overview on the Hock process is given. Next, the mechanism, kinetics, and safety aspects are summarized and discussed. Following, the different types of heterogeneous catalysts and their performance as catalyst in the Hock process are illustrated. Finally, the different approaches to substitute sulfuric acid in the synthetic route to produce phenol are briefly concluded and a short outlook is given.

The kinetics of the reaction methionine+cumene hydroperoxide in the presence of nonionic surfactant was studied both in the pre-micellar and post-micellar regions at different temperatures by iodometry. It was established that the rate of the methionine + cumene hydroperoxide reaction depends on the molecular/ionic/micellar form of surfactant in the reaction system. In the post-micellar region the rate of methionine+cumene hydroperoxide reaction slows down due to solubilization of the reacting substances in the micelles. Quantification of solubilization of cumene hydroperoxide and methionine in the micelles has been studied by HPLC analysis. It was obtained that about 30% of cumene hydroperoxide, which is more hydrophobic than methionine, is solubilized in the micelles, as a result the concentration of cumene hydroperoxide in the reaction environment decreases and the rate of reaction in the post-micellar region also decreases. Based on the kinetic studies the reaction rate constant was determined and the value of activation energy was obtained. [ABSTRACT FROM AUTHOR]

Microcapsules containing initiator of cumene hydroperoxide or tert-butyl peroxy-2-ethylhexanoate as core material and polyurea as shell material were prepared by condensation polymerisation in oil-in-water emulsion at different agitation speeds. And their effects on the polymerisation of methyl methacrylate were investigated by isothermal differential scanning calorimetry. In comparison to unencapsulated initiators, the use of encapsulated initiators significantly delayed the reaction, reduced the maximum heat flow, relatively reduced the maximum reaction rate, and made the conversion smaller. In addition, the encapsulated initiator shortened the time lag, increased the heat flow at the maximum point as the reaction temperature increased, and further delayed the appearance time of the maximum reaction point as the agitation speed decreased. The theoretical values calculated by the modified Kamal model, including the nth-order reaction formula and the autoacceleration reaction, were in good agreement with our experimental data. We observed the more prominent autoacceleration reaction at a higher conversion. [ABSTRACT FROM AUTHOR]

Objectives: A rapid, sensitive and selective analytical method has been developed and validated by liquid chromatography tandem Mass spectrometry (LC-MS/MS) for the quantification of traces of Cumene Hydroperoxide in Esomeprazole magnesium trihydrate active pharmaceutical ingredient. Materials and Methods: The chromatographic separation was carried out on a Develosil Phenyl phase-UG-5 150 x 4.6mm, 3μm column. The mobile phase consisting of 1% Ammonia solution buffer and acetonitrile, the flow rate was 0.9 mL/min with isocratic elution. Results: The retention time of Cumene Hydroperoxide was found 9.25 mins. The developed method was validated according to ICH guidelines. The system suitability was found 4.8% RSD and the linearity calibration curve was linear over the concentration range of 2.309 ppm to 12.747 ppm (r = 0.999). The intraday and inter-day precision (RSD %) was 2.1% and the obtained recovery (%) was at LOQ to 150% is in between 92.4% to 102.8% respectively. Conclusion: The low RSD values and high recoveries of the method confirms the suitability of the method for quantification of Cumene Hydroperoxide in Esomeprazole magnesium trihydrate API. [ABSTRACT FROM AUTHOR]

Dermal exposure to cumene hydroperoxide (CumOOH) during manufacturing processes is a toxicological issue for the industry. Its genotoxicity, mutagenic action, ability to promote skin tumour, capacity to induce epidermal hyperplasia, and aptitude to induce allergic and irritant skin contact dermatitis are well known. These toxic effects appear to be mediated through the activation to free radical species such as hydroxyl, alkoxyl, and alkyl radicals characterised basically by electron paramagnetic resonance (EPR) and spin-trapping (ST) techniques. To be a skin sensitiser CumOOH needs to covalently bind to skin proteins in the epidermis to form the antigenic entity triggering the immunotoxic reaction. Cleavage of the O–O bond allows formation of unstable CumO•/CumOO• radicals rearranging to longer half-life specific carbon-centred radicals R• proposed to be at the origin of the antigen formation. Nevertheless, it is not still clear which R• is precisely formed in the epidermis and thus involved in the sensitisation process. The aim of this work was to elucidate in conditions closer to real-life sensitisation which specific R• are formed in a 3D reconstructed human epidermis (RHE) model by using 13C-substituted CumOOH at carbon positions precursors of potentially reactive radicals and EPR-ST. We demonstrated that most probably methyl radicals derived from β-scission of CumO• radicals occur in RHE through a one-electron reductive pathway suggesting that these could be involved in the antigen formation inducing skin sensitisation. We also describe a coupling between nitroxide radicals and β position 13C atoms that could be of an added value to the very few examples existing for the coupling of radicals with 13C atoms. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Microchannel reactor has been introduced into the CHP decomposition. • The present process affords almost quantitative yield of phenol. • Reduced acid amount and shortened time are required in comparison with kettle reactor. • The microchannel process could also provide higher security of CHP cleavage. • The possible reaction pathway for the CHP cleavage has been proposed. Abstract Phenol is commercially produced through cumene hydroperoxide (CHP) cleavage in kettle reactor, having the disadvantages of hazard potential, low selectivity, low efficiency and complicated process. In the study, microchannel reactor has been introduced into the decomposition using sulfuric acid as the catalyst. The influences of various reaction conditions, including temperature, the ratio of sulfuric acid/CHP and residence time, on the reaction have been studied. Compared with kettle reactor, the present process can afford almost quantitative yield of phenol with reduced acid amount and shortened reaction time under higher reaction temperature. The microchannel process can also provide higher security of CHP cleavage. The microtechnology probably gives an alternative protocol for the production of phenol through CHP decomposition. In addition, the possible main reaction pathways for the CHP cleavage in microchannel reactor have been discussed according to the obtained results. [ABSTRACT FROM AUTHOR]

Highlights • Incorporation of kinetic model into CFD code for CHP decomposition modelling. • Study of reaction course of CHP in CPVT through CFD simulation. • CFD approach is used to visualize the complex phenomena occurred in CHP decomposition. • CFD approach is proposed for scale-up and reactive hazards assessment in industry. Abstract Cumene hydroperoxide (CHP) is prone to thermal decomposition in chemical industry, but there are few reports on the related phenomena in the reactor when decomposition occurs. In order to reveal the complex phenomena of fluid-solid coupled heat transfer, two-phase flow and multi-phase chemical reaction in the CHP decomposition, computational fluid dynamics (CFD) approach was applied to simulate the decomposition of CHP with different mass in a closed pressure vessel. Based on a known reaction scheme and the kinetics evaluated from differential scanning calorimeter (DSC) results, a comprehensive CFD model of CHP decomposition was created. As a result, detailed information on the reaction course was obtained, and distribution of temperature, pressure, reaction rate, and flow velocity in the vessel were also investigated. Finally, closed pressure vessel tests (CPVT) were conducted to verify the validity of the CFD model. This work is conducive to deeply understand the thermal decomposition and reactive hazards assessment of CHP. [ABSTRACT FROM AUTHOR]

We investigated the effects of toxic wastewater generated during the production of phenol-acetone on activated sludge and tested pretreatment methods to selectively remove the toxicity. We found that the microbial activity in the activated sludge was inhibited by the wastewater, in which cumene hydroperoxide (CHP) with a medium effective concentration (EC50) of 225 mg L−1 was the main toxic substance. We tested one pretreatment method with ferrous iron to selectively remove the CHP. The CHP decomposition process, which mainly produced acetophenone, was very quick. The CHP was selectively transformed into low-toxicity organics, and a maximum of 92% was removed when 1.08 mmol L−1 of ferrous iron was added, for a reaction time of 10 min, a pH of 5, and a temperature of 25 °C, and the resulting wastewater only slightly inhibited the oxygen uptake rate of activated sludge. The acclimation of activated sludge was accelerated, and a COD removal rate of more than 85% was achieved within a week. Our results confirm that ferrous iron provides a cost-effective method to selectively remove toxins from wastewater. [ABSTRACT FROM AUTHOR]

In the petrochemical industry, estimation methods based on isothermal micro-calorimetry are used to precisely analyze the thermal hazards and risks associated with chemicals and to develop an inherently safer design (ISD). Here, a thermal activity monitor III (TAM III) was used under various isothermal conditions to obtain the thermokinetics parameters of reaction mechanisms. Cumene hydroperoxide (CHP), a typical organic peroxide, is decomposed by the action of sulfuric acid to yield phenol and acetone in equimolar quantities. CHP undergoes multiple complex reactions when an autocatalytic reaction occurs under isothermal decomposition. The following reaction scheme was considered in this study: A + nB ⇌ (n + 1) B, A ⇌ B, B → C. This type of reaction generally accelerates as the reactant is consumed, and an autocatalytic substance is produced. As a result, an ISD is required for preparation, manufacturing, transportation, storage, and even elimination. The rich behavioral patterns of these autocatalytic reactions were revealed through multiple specific illustrations. [ABSTRACT FROM AUTHOR]

• Kinetics model of CHP decomposition was created based on isothermal data. • Kinetics approach and appropriate heat balance for scale up simulation. • Safety parameters from results can provide information for loss prevention. • Kinetics parameters determined through model-fitting method. • Simulation method for SADT determination was confirmed. In the petrochemical industry, estimation methods based on isothermal micro-calorimetry are used to precisely analyze the thermal hazards and risks associated with chemicals and to develop an inherently safer design (ISD). Here, a thermal activity monitor III (TAM III) was used under various isothermal conditions to obtain the thermokinetics parameters of reaction mechanisms. Cumene hydroperoxide (CHP), a typical organic peroxide, is decomposed by the action of sulfuric acid to yield phenol and acetone in equimolar quantities. CHP undergoes multiple complex reactions when an autocatalytic reaction occurs under isothermal decomposition. The following reaction scheme was considered in this study: A + nB ⇌ (n + 1) B, A ⇌ B, B → C. This type of reaction generally accelerates as the reactant is consumed, and an autocatalytic substance is produced. As a result, an ISD is required for preparation, manufacturing, transportation, storage, and even elimination. The rich behavioral patterns of these autocatalytic reactions were revealed through multiple specific illustrations. [ABSTRACT FROM AUTHOR]

Summary: Oxidation–reduction potential (ORP) is a newer integrated measure of the balance between total oxidants (reactive oxygen species—ROS) and reductants (antioxidants) that reflects oxidative stress in a biological system. This study measures ORP and evaluates the effect of exogenous induction of oxidative stress by cumene hydroperoxide (CH) on ORP in fresh and frozen semen using the MiOXSYS Analyzer. Semen samples from healthy donors (n = 20) were collected and evaluated for sperm parameters. All samples were then flash‐frozen at −80°C. Oxidative stress was induced by CH (5 and 50 μmoles/ml). Static ORP (sORP—(mV/106 sperm/ml) and capacity ORP (cORP—μC/106 sperm/ml) were measured in all samples before and after freezing. All values are reported as mean ± SEM. Both 5 and 50 μmoles/ml of CH resulted in a significant decline in per cent motility compared to control in pre‐freeze semen samples. The increase in both pre‐freeze and post‐thaw semen samples for sORP was higher in the controls than with 50 μmoles/ml of CH. The change from pre‐freeze to post‐thaw cORP was comparable. The system is a simple, sensitive and portable tool to measure the seminal ORP and its dynamic impact on sperm parameters in both fresh and frozen semen specimens. [ABSTRACT FROM AUTHOR]

Intracellular redox status influences the oxidation and enzyme activity of the tumor suppressor phosphatase and tensin homolog on chromosome 10 (PTEN). Cumene hydroperoxide (CuHP), an organic hydroperoxide, is a known tumor promoter. However, molecular targets and action mechanism of CuHP in tumor promotion have not been well characterized. In this study, we investigated the effect of CuHP on the redox state of PTEN in HeLa cells. In addition, the intracellular reducing system of oxidized PTEN was analyzed using a biochemical approach and the effect of CuHP on this reducing system was also analyzed. While PTEN oxidized by hydrogen peroxide is progressively converted to its reduced form, PTEN was irreversibly oxidized by exposure to CuHP in HeLa cells. A combination of protein fractionation and mass analysis showed that the reducing system of PTEN was comprised of NADPH, thioredoxin reductase (TrxR), and thioredoxin (Trx). Although CuHP-mediated PTEN oxidation was not reversible in cells, CuHP-oxidized PTEN was reactivated by the exogenous Trx system, indicating that the cellular Trx redox system for PTEN is inactivated by CuHP. We present evidence that PTEN oxidation and the concomitant inhibition of thioredoxin by CuHP results in irreversible oxidation of PTEN in HeLa cells. In addition, ablation of peroxiredoxin (Prdx) enhanced CuHP-induced PTEN oxidation in cells. These results provide a new line of evidence that PTEN might be a crucial determinant of cell fate in response to cellular oxidative stress induced by organic hydroperoxides. [ABSTRACT FROM AUTHOR]