Abstract: The present invention relates to a method for reducing/suppressing sheeting or agglomerates during polymerization of olefins, especially during the fluidized bed gas phase polymerization of olefins. In particular, the present invention relates to a method for reducing/suppressing sheeting or agglomerates during the product grade transition and/or catalyst transitions occurring polymerization of olefins.

Abstract: The present invention relates to a catalyst system which is a mixture of at least two catalytic species, the first catalytic species being a dehydrogenation catalyst and the second catalytic species being an epoxidation catalyst and comprising silver. The present invention also relates to a process for the production of epoxides, in particular a process for the production of an epoxide from an alkane or a mixture comprising an alkane and an alkene, which process comprises contacting said alkane or mixture comprising said alkane and said alkene and a source of oxygen with such a catalyst system comprising a mixture of at least two catalytic species, the first catalytic species providing dehydrogenation activity and the second catalytic species providing epoxidation activity and comprising silver.

Abstract: A process for the polymerisation of ethylene or the copolymerisation of ethylene and alpha-olefins in the presence of a catalyst system comprising—as components (a) a transition metal compound, (b) a non-aluminoxane activator, and (c) optionally a support, comprises the use of a prepolymer prepared by contact of the catalyst components with ethylene and/or one of more alpha-olefins at a temperature in the range 60° C. to 100° C. The prepolymer may be isolated or used in situ for the polymerisation of ethylene or the copolymerisation of ethylene and alpha-olefins in particular 1-hexene. By use of the process thermal stability of the catalyst is improved leading to increased activity without any deterioration in polymer morphology.

Abstract: A method of determining or predicting a value P.sub.x of a property (e.g. octane number) of a material X or a property of a product of a process from the material or yield of the process for example a blending, separation, or chemical (e.g. polymerization) process, which method comprises measuring the absorption D.sub.ix of the material at more than one wavelength in the region 600-2600 nm, comparing the the signals indicative of the absorptions or a derivative thereof with signals indicative of absorptions D.sub.im or derivatives thereof at the same wavelength for a number of standards S in a bank for which the property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m the standard having the smallest average value of the absolute difference at each wavelength i between the signal for the material and the signal for the standard S.sub.m to obtain P.sub.x, with averaging of the properties or yields P.sub.m when more than one standard S.sub.m is chosen.

Abstract: A method of determining or predicting a value P.sub.x of a property of a feed X to a steam cracking process or yield of said process, which method comprises measuring the absorption D.sub.ix of said material at more than one wavelength in the region 600-2600 nm, comparing signals indicative of said adsorptions or a mathematical function thereof with signals indicative of absorptions D.sub.im or mathematical function thereof at the same wavelength for a number of standards S in a bank for which the said property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m said standard having the smallest average value of the absolute difference at each wavelength i between the signal for the material and the signal for the standard S.sub.m to obtain P.sub.x, with averaging of said properties or yields P.sub.m when more than one standard S.sub.m is chosen. If desired the method can be used as such to control the steam cracking process by comparison of P.sub.

Abstract: An apparatus for on-line measuring physical property data of hydrocarbon products such as octane number, cetane number, density, vapour pressure and the like or gasoline/alcohol ratio, comprising means for providing (N)IR radiation in a predetermined spectral range; means for transmitting light at selected wavelengths in the (N)IR spectral region; means for delivering light from said transmitting means to a hydrocarbon product line; means for allowing an optical path length in the hydrocarbon product line; means for detecting the light transmitted through the said optical path; means for providing the obtained signal to be input to processing equipment for spectral analysis and correlating the spectral data to the physical property data of hydrocarbon products such as octane number, cetane number, density, vapour pressure and the like or gasoline/alcohol ratio.

Abstract: A method of determining or predicting a value P.sub.x of a property of a material X, which is a feed to a process or a property of a product of a process from said material or yield of said process, which method comprises measuring the absorption D.sub.i x of said material at more than one wavelength in the region 600-2600 nm, comparing the said absorptions or a derivative thereof with absorptions D.sub.i m or derivatives thereof at the same wavelength for a number of standards S in a bank for which the said property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m said standard having the smallest average value of the absolute difference at each wavelength i between the absorption D.sub.i x (or derivative thereof) for the material and the absorption D.sub.i m (or derivative thereof) for the standards S.sub.m to obtain P.sub.x, with averaging of said properties or yields P.sub.m when more than one standard S.sub.

Abstract: A method of determining or predicting a value P.sub.x of a property of a material X, which is a feed to a process or a property of a product of a process from said material or yield of said process, which method comprises measuring the absorption D.sub.i x of said material at more than one wavelength in the region 600-2600 nm, comparing the said absorptions or a derivative thereof with absorptions D.sub.i m or derivatives thereof at the same wavelength for a number of standards S in a bank for which said property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m said standard having the smallest average value of the absolute difference at each wavelength i between the absorption D.sub.i x (or derivative thereof) for the material and the absorption D.sub.i m (or derivative thereof) for the standard S.sub.m to obtain P.sub.x, with averaging of said properties or yields P.sub.m when more than one standard S.sub.

Abstract: A method of determining or predicting a value P.sub.x of a property (e.g. octane number) of a material X or a property of a product of a process from said material or yield of said process, which method comprises measuring the absorption D.sub.ix of said material at more than one wavelength in the region 600-2600 nm, comparing the said absorptions or a derivative thereof with absorptions D.sub.im or the derivatives thereof at the same wavelength for a number of standards S in a bank for which the said property or yield P is known, and choosing from the bank at least one standard S.sub.m with property P.sub.m said standard having the smallest average value of the absolute difference at each wavelength i between the absorption D.sub.i x (or derivative thereof) for the material and the absorption D.sub.i m (or derivative thereof) for the standard S.sub.m to obtain the P.sub.x, with averaging of said properties or yields P.sub.m when more than one standard S.sub.m is chosen.