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Decomposition of ethylene

Recklinghausen, K. 1978. Method and Devise for Protecting Ethylene Oxide Producing and Processing Plants Against the Decomposition of Ethylene Oxide. German Patent Submission No. P28.50254.7 (November 20, 1978). [Pg.136]

When ethylene is polymerized, the reactor temperature should be well controlled to avoid the endothermic decomposition of ethylene to carbon, methane, and hydrogen ... [Pg.326]

Fig.3 shows an effect of titanium dioxide loading on the decomposition of ethylene over a 20mesh wire-net photocatalyst. The decomposition rate increased in proportion to the amount of titanium dioxide loaded The specific initial rate (ro=(-dc/dt)t=o) was (1.8 0.2)x 10 ppm s g-catalysf. ... [Pg.242]

Effect of titanium dioxide loading on decomposition of ethylene... [Pg.243]

In this work, effects of atmosphere during calcination process on photoactivities for decomposition of ethylene were investigated. TiOa were prepared by sol-gel and then calcined under Na plus increasing amounts of O2 at temperature 723 K. Conversion of ethylene increased with increasing sirface defect. Increasing this defect occurred when amount of O2 during calcination process increased. Surface defect of Ti02 samples was determined by CO2-TPD and ESR, while XRD, SEM, TEM and BET were used to characterize other physical properties of TiOa samples. [Pg.717]

In our experiment, photocatalytic decomposition of ethylene was utilized to probe the surface defect. Photocatalytic properties of all titania samples are shown in table 2. From these results, conversions of ethylene at 5 min and 3 hr were apparently constant (not different in order) due to the equilibrium between the adsorption of gaseous (i.e. ethylene and/or O2) on the titania surface and the consumption of surface species. Moreover it can be concluded that photoactivity of titania increased with increasing of Ti site present in titania surface. It was found that surface area of titania did not control photoactivity of TiOa, but it was the surface defect in titania surface. Although, the lattice oxygen ions are active site of this photocatalytic reaction since it is the site for trapping holes [4], this work showed that the presence of oxygen vacancy site (Ti site) on surface titania can enhance activity of photocatdyst, too. It revealed that oxygen vacancy can increase the life time of separated electron-hole pairs. [Pg.720]

Other sources indicate that decomposition can take place at 350 C under 170 bar and in the absence of air. In this case, the temperature reaches 1350°C and the pressure is multiplied by six. An estimation of the enthalpy of decomposition gives AH = -4.33 kJ/g. The violent pressure increase also causes the decomposition of ethylene. [Pg.236]

The rate of decomposition of ethylene oxide, C2H4CKA), to CH4 and CO, has been studied by Crocco et al. (1959) at 900-1200 K in a flow reactor. They found the rate constant to be... [Pg.171]

Pesetsky, B., J. N. Cawse, and W. T. Vyn, "Liquid Phase Decomposition of Ethylene Oxide," CEP Technical Manual, Loss Prevention, 13,123 (1980), American Institute of Chemical Engineers, New York, NY. [Pg.191]

The tabulated data have been obtained for the vapor phase decomposition of ethylene oxide (A) into methane and carbon monoxide at 414.5°C (Heppert Mack, JACS 5J 2706, 1929). Show that the rate equation is first order, nt = 2na0-na... [Pg.170]

The chemisorption and thermal decomposition of ethylene over platinum (111) surfaces have been extensively studied by several groups using a range of modern surface science techniques (1-3 ). Chemisorption at low temperatures is molecular, with the... [Pg.131]

Hylin, J.W. Oxidative decomposition of ethylene-bis-dithiocarbamates. Bull. Environ. Contam. Toxicol, 10(4) 227-233,1973. [Pg.1672]

Explosibility. Liquid ethylene oxide is stable to detonating agents, but the vapor will undergo explosive decomposition. Pure ethylene oxide vapor will decompose partially however, a slight dilution with air or a small increase in initial pressure provides an ideal condition for complete decomposition. Copper or other acetylide-forming metals such as silver, magpesium, and alloys of such metals should not be used to handle or store ethylene oxide because of the danger of the possible presence of acetylene. Acetylides detonate readily and will initiate explosive decomposition of ethylene oxide vapor. In the presence of certain catalysts, liquid ethylene oxide forms a poly-condensate. [Pg.156]

The gaseous products formed on thermal decomposition of ethylene-platinous chloride are ethylene, hydrogen chloride, vinyl chloride, ethyl chloride, ethylene dichloride and ethylidine dichloride. The half life for the decomposition at 130° is 4.5 days, at 172° it is 1.7 hours 98). The hydrolysis of Zeisc s salt K[PtCl3(C2H4)] by water and dilute acids has been studied ... [Pg.98]

For good detergency the length of the ethenoxy chain should carefully balance the hydrophobic part of the molecule. In the above example, from eight to ten such groups appear to be optimum. The ethylene oxide for these products comes from petroleum ethylene, either by direct oxidation or decomposition of ethylene chlorohydrin (17). [Pg.332]

The radical polymerization of ethylene, in practice, is initiated by free-radical initiators, although radiation-induced,155 210 photoinduced,211-213 and thermal213,214 initiations are also possible. The temperature of high-pressure polymerization should not exceed 350°C since above this temperature a rapid exothermic (AH = —30.4kcal/mol) thermal decomposition of ethylene can take place leading to a runaway reaction ... [Pg.744]

Loss prevention of polyethylene plants is outlined in Chapter 7.2. The major hazard that can occur is the runaway of the high-pressure reactor and decomposition of ethylene besides fire and disintegration of high-pressure separators, pipes, and compressors. The critical conditions for runaway and ethylene decomposition during homo- and copolymerization are revealed together with the influence of decomposition sensitizers. Relief devices and venting systems are described. [Pg.405]

Figure 7.1-2. Critical conditions of decomposition of ethylene starting from hot spot. , no decomposition O, decomposition monomer pure ethylene method ignition by hot wire at relative low energies. Figure 7.1-2. Critical conditions of decomposition of ethylene starting from hot spot. , no decomposition O, decomposition monomer pure ethylene method ignition by hot wire at relative low energies.
The major hazard that can occur in the high-pressure polyethylene process is a runaway of the reactor and decomposition of ethylene as well as fires, explosion, and disintegration of high-pressure parts. Although the last incidents are well understood, the reasons for runaway and ethylene decomposition have been evaluated only recently. Experience over twenty years has shown that decomposition mostly takes place in the reactor and in the high-pressure separator, but decompositions have also been reported from ethylene-feed and product lines. [Pg.421]

The exact order of events leading to these familiar aperies still remains obscure, however. Cvetsnovic has called attention to the similarity between the photolytio decomposition of ethylene oxide and the fete of energy-rich intermediates formed during high temperature catalytic ethylene oxidation. 00 4 1... [Pg.337]

Under ordinary conditions, this may not be a major reaction, but for the problem of acetylene formation it is notable that Cvetanovic and Callear (19), and Mitchell and Le Roy (49), in studies of the photosensitized decomposition of ethylene, found a uni-molecular mechanism. Ingold and Stubbs (33) also found that the decomposition of propylene starts with a molecular rearrangement and decomposition ... [Pg.53]


See other pages where Decomposition of ethylene is mentioned: [Pg.460]    [Pg.2313]    [Pg.123]    [Pg.87]    [Pg.87]    [Pg.241]    [Pg.241]    [Pg.242]    [Pg.68]    [Pg.295]    [Pg.296]    [Pg.296]    [Pg.123]    [Pg.135]    [Pg.282]    [Pg.84]    [Pg.337]    [Pg.122]    [Pg.460]    [Pg.329]    [Pg.329]    [Pg.330]    [Pg.27]    [Pg.288]    [Pg.289]    [Pg.289]   
See also in sourсe #XX -- [ Pg.28 , Pg.91 ]

See also in sourсe #XX -- [ Pg.220 , Pg.225 ]




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Ethylene decomposition

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