A process produces sodium and/or potassium alkoxides in countercurrent by reactive rectification. Alcohol is reacted in countercurrent with the respective alkali metal hydroxide. The vapours containing alcohol and water are separated into at least two serially arranged rectification columns. The energy of the vapour obtained in the first rectification is utilized for operating the second rectification. This specific energy integration coupled with establishing a certain pressure difference in the two rectification stages makes it possible to cover a particularly large proportion of the energy required for the rectification through electricity and to save heating steam.

Provided is an olefin polymerization catalyst carrier with a general structure formula of Mg(OR.sup.I).sub.n(OR.sup.II).sub.2-n, wherein: 0≦n≦2, and R.sup.I and R.sup.II can be the same or different and are each independently selected from a C.sub.1-C.sub.20 hydrocarbon group. In the X-ray diffraction pattern of the catalyst carrier, there are a set of diffraction peaks in the range of a 2θ diffraction angle of 5°-15°, and the set of diffraction peaks contain 1-4 main diffraction peaks. Also disclosed is an olefin polymerization solid catalyst component which is prepared from the carrier Mg(OR.sup.I).sub.n(OR.sup.II).sub.2-n, a titanium compound, and at least one electron donor compound. In addition, also disclosed is an olefin polymerization catalyst containing the solid catalyst component, at least one organic aluminum compound, and optionally, an external electron donor compound.

Provided is an olefin polymerization catalyst carrier with a general structure formula of Mg(OR.sup.I).sub.n(OR.sup.II).sub.2-n, wherein: 0≦n≦2, and R.sup.I and R.sup.II can be the same or different and are each independently selected from a C.sub.1-C.sub.20 hydrocarbon group. In the X-ray diffraction pattern of the catalyst carrier, there are a set of diffraction peaks in the range of a 2θ diffraction angle of 5°-15°, and the set of diffraction peaks contain 1-4 main diffraction peaks. Also disclosed is an olefin polymerization solid catalyst component which is prepared from the carrier Mg(OR.sup.I).sub.n(OR.sup.II).sub.2-n, a titanium compound, and at least one electron donor compound. In addition, also disclosed is an olefin polymerization catalyst containing the solid catalyst component, at least one organic aluminum compound, and optionally, an external electron donor compound.

One or more concentrated low-viscosity solutions of alkaline earth alkoxide compounds M(OCH.sub.2R.sup.6).sub.2-a-b(OR.sup.7).sub.a[O(CHR.sup.8)OR.sup.9].sub.b in mixture with a metal alkyl compound M(R.sup.10R.sup.11) in an aprotic solvent and related methods are disclosed herein.

One or more concentrated low-viscosity solutions of alkaline earth alkoxide compounds M(OCH.sub.2R.sup.6).sub.2-a-b(OR.sup.7).sub.a[O(CHR.sup.8)OR.sup.9].sub.b in mixture with a metal alkyl compound M(R.sup.10R.sup.11) in an aprotic solvent and related methods are disclosed herein.

The invention relates to hydrocarbon-soluble halogen or thiolate/magnesium exchange reagents of the general formula
R.sup.1MgR.sup.1.sub.1-n(OR.sup.3).sub.n.LiOR2.(1−n)LiOR.sup.3.aDonor
in which: R.sup.1 is a C1-C8 alkyl and OR.sup.2 as well as OR.sup.3 are same or different and represent primary, secondary, or tertiary alkoxide residues having 3 to 18 carbon atoms, wherein R.sup.2 and/or R.sup.3 can for their part contain an alkoxy substituent OR.sup.4; a assumes a value of 0 to 2, n assumes a value between 0 and 1, and the donor is an organic molecule containing at least 2 nitrogen atoms.

The invention relates to hydrocarbon-soluble halogen or thiolate/magnesium exchange reagents of the general formula
R.sup.1MgR.sup.1.sub.1-n(OR.sup.3).sub.n.LiOR2.(1−n)LiOR.sup.3.aDonor
in which: R.sup.1 is a C1-C8 alkyl and OR.sup.2 as well as OR.sup.3 are same or different and represent primary, secondary, or tertiary alkoxide residues having 3 to 18 carbon atoms, wherein R.sup.2 and/or R.sup.3 can for their part contain an alkoxy substituent OR.sup.4; a assumes a value of 0 to 2, n assumes a value between 0 and 1, and the donor is an organic molecule containing at least 2 nitrogen atoms.

The magnesium alkoxide particle contains the reaction product of the following components: 1) a magnesium powder; 2) a mixed alcohol; 3) a halogenating agent; and 4) a titanate compound. The magnesium alkoxide particle is used for preparing a catalyst for olefin polymerization.

One or more concentrated low-viscosity solutions of alkaline earth alkoxide compounds M(OCH.sub.2R.sup.6).sub.2-a-b(OR.sup.7).sub.a[O(CHR.sup.8).sub.nOR.sup.9].sub.b in mixture with a metal alkyl compound M(R.sup.10R.sup.11) in an aprotic solvent and related methods are disclosed herein.

One or more concentrated low-viscosity solutions of alkaline earth alkoxide compounds M(OCH.sub.2R.sup.6).sub.2-a-b(OR.sup.7).sub.a[O(CHR.sup.8).sub.nOR.sup.9].sub.b in mixture with a metal alkyl compound M(R.sup.10R.sup.11) in an aprotic solvent and related methods are disclosed herein.