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Yihwen Wang - One of the best experts on this subject based on the ideXlab platform.
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thermal runaway hazards of Cumene Hydroperoxide with contaminants
Industrial & Engineering Chemistry Research, 2001Co-Authors: Yihwen WangAbstract:Cumene Hydroperoxide (CHP) has been used in producing phenol and acetone by catalytic cleavage and as an initiator in polymerization. However, many severe fires and explosions have occurred because of its thermal instability and incompatibility. In fact, CHP has been given a hazard classification of flammable type or Class III by the National Fire Protection Association (NFPA). To date, however, its reactive and incompatible hazards have not yet been clearly identified. In this study, the thermal decomposition and runaway behaviors of CHP with about 1 wt % incompatibilities such as H2SO4, HCl, NaOH, KOH, Fe2O3, FeCl3, and Fe2(SO4)3 were analyzed by DSC thermal analysis and VSP2 adiabatic calorimetry. The thermokinetic data obtained via calorimetry, such as onset temperature, heat of decomposition, adiabatic temperature rise, and self-heat rate, were also compared with those of CHP in Cumene. Hydroxide ion and ferric ion were found to be quite incompatible with CHP. The worst case of thermal runaway of CHP...
A. Van Der Laarse - One of the best experts on this subject based on the ideXlab platform.
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Cumene Hydroperoxide induced changes in calcium homeostasis in cultured neonatal rat heart cells
Cardiovascular Research, 1992Co-Authors: M. Persoon-rothert, J.m. Egas-kenniphaas, E.j.m. Van Der Valk-kokshoorn, A. Van Der LaarseAbstract:Objective: The relationship between oxidative stress induced cell necrosis and perturbation of intracellular calcium homeostasis was investigated in cultured myocytes. Methods: Cultured neonatal rat heart cells were loaded with fura-2 AM to measure cytosolic free calcium ([Ca2+]i). Probenecid, an inhibitor of organic anion transport, was present during the experiment to reduce efflux of fura-2 from the cytoplasm. Cells were exposed to Cumene Hydroperoxide, a toxic organic Hydroperoxide that is known to induce oxidative stress in myocytes. The efficacy of the protective agents Trolox C (a vitamin E analogue) and chlorpromazine (a phospholipase inhibitor) on Cumene Hydroperoxide induced cell injury was determined. Results: [Ca2+]i in control cells was constant (60 nM) during an incubation time of 45 min. Probenecid did not affect [Ca2+]i levels or cell viability under the experimental conditions. Cumene Hydroperoxide caused a sustained rise in [Ca +]i starting after 5-10 min, to a level of 1300 nM at 45 min. After 20-25 min the viability of the heart cells started to decline and after 45 min 44% of the cells were irreversibly injured. The loss of cell viability was expressed as percentage decrease of the fluorescence at 360 nm (the calcium independent wavelength), since the percent release of cellular α-hydroxybutyrate dehydrogenase (α-HBDH) activity equalled the percent decrease of the fluorescence at 360 nm. Trolox C and chlorpromazine almost completely prevented the Cumene Hydroperoxide induced α-HBDH release. The [Ca2+]i of myocytes incubated with Cumene Hydroperoxide in combination with Trolox C rose to 1000 nM without affecting cell viability. The Cumene Hydroperoxide induced rise in [Ca2+]i was markedly reduced by chlorpromazine (at t=45 min, [Ca2+]i=360 nM). Addition of Trolox C to untreated cells did not influence [Ca2+]i, whereas chlorpromazine alone induced a slight increase of [Ca2+]i up to 360 nM with complete preservation of cell viability. Conclusions: Trolox C and chlorpromazine are very effective inhibitors of Cumene Hydroperoxide induced perturbation of calcium homeostasis and subsequent cell death. A role for peroxidation of membrane phospholipids and activation of calcium dependent phospholipase in the cascade of events leading to irreversible injury is suggested.
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Prevention of Cumene Hydroperoxide induced oxidative stress in cultured neonatal rat myocytes by scavengers and enzyme inhibitors.
Journal of Molecular and Cellular Cardiology, 1990Co-Authors: M. Persoon-rothert, J.m. Egas-kenniphaas, E.j.m. Van Der Valk-kokshoorn, I. Mauve, A. Van Der LaarseAbstract:Abstract Oxidative stress induced by Cumene Hydroperoxide was studied in cultured neonatal rat myocytes. A progressive increase of irreversible cell injury as determined by leakage of the cytoplastic enzyme α-hydroxybutyrate dehydrogenase (α-HBDH) from the cells was noted at concentrations ranging from 25–100 μ m Cumene Hydroperoxide (incubation time 90 min). Cumene Hydroperoxide-induced damage was reduced or prevented by several compounds: the application of Trolox C, a water-soluble vitamin E analogue, and of phospholipase A 2 inhibitors chlorpromazine and (to a lesser extent) quinacrine prevented α-HBDH release. ICRF-159, a chelator of divalent cations, ascorbic acid, a potent antioxidant, and the cysteine protease inhibitor leupeptin did not reduce the Cumene Hydroperoxide-induced cytotoxicity. Detoxification of Hydroperoxides by the glutathione peroxidase system results in an increased flux through the pentose phosphate shunt and loss of NADPH. Glucose inhibited the Cumene Hydroperoxide-induced α-HBDH release, probably by replenishing NADPH. These results indicate that Cumene Hydroperoxide, after exhaustion of the glutathione system, induces irreversible injury in cultured myocytes by a mechanism that depends to a large extent on deterioration of cellular membranes caused by lipid peroxidation and phospholipase activation.
Yu Lin-hong - One of the best experts on this subject based on the ideXlab platform.
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Novel Technology for Synthesis of Propylene Oxide Using Cumene Hydroperoxide as Oxidant
Chemical Propellants & Polymeric Materials, 2007Co-Authors: Yu Lin-hongAbstract:The uses, synthesis technology and economic situations at home and abroad of propylene oxide are introduced. The propylene oxide synthesis process of Sumitomo Chemical Corporation using Cumene Hydroperoxide as oxidant is introduced in detail. It includes Cumene oxidation, propylene epoxidation, recovery and purification of propylene and propylene oxide, dehydration and hydrogenation of cumyl alcohol as well as harmful impurities removal, and so on. The integrated process does not produce any co- products. The plant cost is lower about one third than that of the traditional Halcon process.
Huang Da-gang - One of the best experts on this subject based on the ideXlab platform.
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Decomposition of Cumene Hydroperoxide Catalyzed by Resins——II.Reaction Process
The Chinese Journal of Process Engineering, 2001Co-Authors: Huang Da-gangAbstract:Since Na+ exists in the water phase rather than the oil phase (Cumene Hydroperoxide), the separation of oil and water for Na+ removal reaches equilibrium after water washing and standing for 30 min. When the volumetric ratio of oil to water is 5, nearly 100% of Na+ can be removed from Cumene Hydroperoxide. When the solid catalyst hold-up in a reactor is less than 0.8%, the rate of decomposition reaction increases linearly with the increase of the solid hold-up. However, when the solids hold-up of catalyst is more than 0.8%, the rate of decomposition hardly increases with the increase of the solid hold-up because mass transfer is now the rate-determining step. Similarly, the influence of reaction temperature on the reaction rate is not as remarkable as expected because mass transfer is depressed. In addition, with the increase of water content, the reaction rate decreases, so the water content in raw material must be controlled to a very low level. Based on the reaction conditions, a novel three-phase circulating fluidized-bed (TPCFB) is proposed and used as the reactor for the decomposition of Cumene Hydroperoxide. The hot model experiments show that the reaction pr℃eeds steadily and Cumene Hydroperoxide in the product is less than 0.1% which can meet industrial requirement.
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Decomposition of Cumene Hydroperoxide Catalyzed by Resin Catalysts
The Chinese Journal of Process Engineering, 2001Co-Authors: Huang Da-gangAbstract:Comparing different sulfonic resin catalysts, it was found that CT-175 has a higher activity and is suitable catalyst for the decomposition of Cumene Hydroperoxide. After the wet resin is dipped in acetone for more than 80 min, nearly 100% water can be removed when the ratio of acetone to resin is 40 ml/g. The main reason of resin fragmentation is mechanical stirring, so it is not suited for a reactor with a mechanical stirrer. The deactivation of resin is caused by Na+ in the resin, and the deactivated catalyst must be regenerated after the Na+ concentration is more than 3%. The optimal regeneration condition is room temperature and 3.5% (() H2SO4 solution by which more than 95% Na+ in the resin can be removed.
Mohammad Reza Eskandari - One of the best experts on this subject based on the ideXlab platform.
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hepatoprotective activity of cucumis sativus against Cumene Hydroperoxide induced oxidative stress
Research in Pharmaceutical Sciences, 2012Co-Authors: H Heidari, Mohammad Kamalinejad, Mohammad Reza EskandariAbstract:Background and Aims: The fruit of Cucumis sativus a plant that has long been used in oriental medicine for its anti inflammatory, antidiabetic, and abortifacient effects. Cucumis sativus belonging to Cucurbitaceae family is commonly known as Cucumber. Based on its traditional use the fruit of the plant was selected for free radical scavenging and antioxidant activities. In this study we planned to study hepatoprotective effect of aqueous extract of Cucumis sativus fruit against cytotoxicity and reactive oxygen species (ROS) production, using accelerated cytotoxicity mechanisms screening (ACMS) techniques in isolated Sprague–Dawley rat hepatocytes as a cellular model. Method: Fresh fruits of Cucumis sativus were cleaned, and then dried in shade at room temperature and aqueous extract of the fruit was obtained. Hepatocytes were obtained by collagenase perfusion of the liver and viability was assessed by plasma membrane disruption determined by trypan blue (0.2 w/ v) exclusion test. To determine the rate of hepatocyte reactive oxygen species (ROS) generation induced by Cumene Hydroperoxide, dichlorofluorescin diacetate (DCFH-DA) was added to the hepatocytes. The latter then reacts with ROS to form the highly fluorescent dichlorofluorescein (DCF), which effluxes the cell. The fluorescence intensity of DCF was measured. Results: In the present study, the antioxidative potential of Cucumis sativus was evaluated in isolated rat hepatocytes and we tried to figure out whether Cucumis sativus could protect hepatocytes against Cumene Hydroperoxide (CHP) induced-cytotoxicity and ROS formation. Our results showed that when isolated hepatocytes were incubated with CHP, there was an initial rapid increase in ROS formation, which was prevented by aqueous extract of Cucumis sativus fruit. Conclusions: Our results showed that aqueous extract of Cucumis sativus acts as a hepatoprotective and antioxidant agent against CHP-induced hepatotoxicity suggesting that antioxidants and radical scavenging components of Cucumis sativus fruit extract can easily cross the cell membrane and cope with the intracellular ROS formation.
