Ethylene Consumption Research Articles

Ligand field effects on kinetic profiles in ethylene, alpha-olefin copolymerization

One of the more popular fields of study in inorganic chemistry revolves around the examination of the effects of ligand field changes on the reactivity patterns of transition metal ions. By varying the size, number and type of first coordination sphere ligand fields, a variety of reactivities can be induced to occur at the metal center. Employing this approach, a series of novel Ti(IV) complexes having different ligand fields has been synthesized, characterized and employed as Ti sources in high efficiency, high temperature heterogeneous Ziegler style alpha-olefin polymerization catalysts. Dramatic changes in catalyst efficiencies,exotherms and ethylene consumption rates can be induced by altering the ligand field of the Ti center. These effects are discussed in detail.

Effect of various factors on the kinetics of ethylene consumption during its polymerization on the surface of kaolin particles treated with organo-aluminium compounds

The effect of the following factors on the kinetics of ethylene consumption during its polymerization on the surface of kaolin particles has been studied: the temperature of drying pressure of ethylene; temperature; duration of the pre-contact treatment of the kaolin. Methods and the type of kaolin; the concentration and type of organo-aluminium compound; the for best carrying out the process of polymerization filling are proposed.It is suggested that the catalytic activity of treated kaolin is determined by titanium, vanadium and (or) chromium compounds that are present in the kaolin.

Kinetics of ethylene polymerization at high temperature with Ziegler–Natta catalysts

A kinetic technique is developed for the study of ethylene polymerization reaction at high temperature with Ziegler–Natta catalysts. The technique is based on the calculation of polymerization rate parameters from the data on ethylene consumption vs. time. It takes into account increase of reaction temperature at the beginning of the reaction. Kinetic data in coordinates “polymerization rate–time” are presented for several pseudohomogeneous catalysts (TiCl4AlEt2Cl, Ti(OiC3H7)4AlEt2Cl), heterogeneous catalysts (δ-TiCl3AlEt3, δ-TiCl3AlEt2Cl, TiCl4/MgCl2AlEt3, TiCl4/MgCl2AlEt2Cl) and solubilized catalysts (δ-TiCl3poly-1-hexeneAlEt2Cl) at 180°C and reaction pressure 14.6 atm for first 10 min of the reaction. These data are useful for the selection of Ziegler–Natta catalysts for testing in ethylene polymerization reaction in continuous high pressure reactors at short residence times.

A comparative study of ethylene oxidation inVicia faba andMycobacterium paraffinicum

Vicia faba L. ‘Herz Freya’ (fababean) cotyledons andMycobacterium paraffinicum Bardane strain (MPB) cells were studied to describe and compare physiological and biochemical factors regulating ethylene oxidation. Both organisms demonstrated a linear rate of ethylene uptake as a function of concentration from 1 ppm to 1,000 ppm. CO2 did not influence ethylene oxidation by either organism. Zero degree temperatures and CO inhibited ethylene oxidation by fababeans but not by MPB. An N2 gas phase blocked ethylene consumption by fababeans. In contrast, MPB continued to consume ethylene at a reduced rate under anaerobic conditions. Hydrocarbon oxidation was limited to alkenes. Alkanes were not oxidized by either organism. Both organisms were sensitive to diethyldithiocarbamic acid, o-phenanthroline, carbonyl cyanidem-chlorophenyl hydrazone, and CS2. The possibility that CS2 acted as a suicide substrate is discussed. Evidence is presented that hydrocarbon gas oxidation by fababeans is not a part of, or reflection of, the way ethylene acts as a hormone.

Main reaction of peroxy radicals in the gas-phase oxidation of ethylene

Experimental data for the free radical concentration and the rates of ethylene consumption and ethylene oxide formation indicate that the peroxy radicals in the gas-phase oxidation of ethylene are mainly involved in the epoxidation of ethylene, whose rate constant is $$k = 2.1 \times 10^{ - 12} \exp ( - \frac{{13760}}{{RT}})cm^3 particle^{ - 1} s^{ - 1} $$

The role of slow electrons in the effect of alcohols on the γ-radiolysis of ethylene

Abstract When ethylene, containing a small amount of gaseous alcohol, was irradiated by gamma rays, the G(- C2H4) had a maximum value at the addition of ethyl, isopropyl or t-butyl alcohol less than 0.03 electron fraction. The total concentration of mixtures was 1.1 × 10−4 mole/cc. On the other hand, the appearance potential of negative ions, formed by dissociative-resonance-electron-capture processes of slow-electron impact, was measured by mass spectrometer. The lowest value for ethanol (2.7 eV) was much lower than that for ethylene (7.9 eV). This fact suggests that slow electrons in the system are more or less captured by alcohols added to retard the neutralization of positive ethylene ions. The enhancement of the ethylene consumption by adding alcohols is, therefore, attributed to the ion-molecule reactions, that is, the ionic polymerization of ethylene.

Ethylene production and consumption in Japan

Ethylene production and consumption in Japan