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CN-122028980-A - Aqueous process for titanating chromium/silica catalysts with alkali metals

CN122028980ACN 122028980 ACN122028980 ACN 122028980ACN-122028980-A

Abstract

Methods of preparing a titanated silica support, a titanated chromium/silica pre-catalyst and an activated titanated chromium/silica catalyst are disclosed wherein hydrogen peroxide and an alkali metal precursor are used during catalyst preparation. The resulting titanated chromium/silica pre-catalyst typically contains silica, 0.1 to 5% by weight chromium, 0.1 to 10% by weight titanium and less than or equal to 4% by weight carbon, and also contains an alkali metal or zinc in combination in a molar ratio of alkali metal to titanium to zinc of 0.02:1 to 3:1 and/or in an amount of 0.01 to 2mmol of the corresponding alkali metal or zinc per gram of the silica. The high melt index potential activated chromium titanate/silica catalysts can be used to polymerize olefins to produce ethylene-based homopolymers and copolymers having, for example, HLMI values greater than 30g/10 min.

Inventors

  • A. Ramanathan
  • M.P. MCDANIEL
  • JAMES L. BALL
  • A. T. Prague
  • C, E, Victor
  • SOLENBERGER ALAN L.
  • Z. T. Kilpatrick
  • M. P. Stevens

Assignees

  • 切弗朗菲利浦化学公司

Dates

Publication Date
20260512
Application Date
20241022
Priority Date
20231024

Claims (20)

  1. 1. A carrier of titanated silicon dioxide, the titanated silica support comprises: Silicon dioxide; 0.1 to 10 wt% titanium; 0.5 to 12% by weight of water; Less than or equal to 4 weight percent carbon, and An alkali metal in a bound state and/or zinc in a bound state; wherein the molar ratio of the combined alkali metal to the titanium and/or the combined zinc to the titanium is from 0.02:1 to 3:1, and/or Wherein the amount of said bound alkali metal and/or said bound zinc is in the range of 0.01mmol to 2mmol of said bound alkali metal or said bound zinc per gram of said silica.
  2. 2. A chromium titanate/silica pre-catalyst, the chromium titanate/silica pre-catalyst comprising: Silicon dioxide; 0.1 to 5% by weight of chromium; 0.1 to 10 wt% titanium; 0.5 to 12% by weight of water; Less than or equal to 4 weight percent carbon, and An alkali metal in a bound state and/or zinc in a bound state; wherein the molar ratio of the combined alkali metal to the titanium and/or the combined zinc to the titanium is from 0.02:1 to 3:1, and/or Wherein the amount of said bound alkali metal and/or said bound zinc is in the range of 0.01mmol to 2mmol of said bound alkali metal or said bound zinc per gram of said silica.
  3. 3. The pre-catalyst of claim 2, wherein the pre-catalyst comprises 0.3 wt% to 3 wt%, 0.4 wt% to 2 wt%, 0.5 wt% to 1.5 wt%, or 0.7 wt% to 1.5 wt% of the chromium.
  4. 4. A pre-catalyst as claimed in claim 2 or 3, wherein at least 75 wt%, at least 80 wt%, at least 90 wt% or at least 95 wt% of the chromium is present in an oxidation state of 3 or less.
  5. 5. The support or pre-catalyst of any one of claims 1 to 4, wherein the support or pre-catalyst comprises less than or equal to 3 wt%, less than or equal to 2 wt%, less than or equal to 1 wt%, less than or equal to 0.5 wt%, less than or equal to 0.3 wt%, or less than or equal to 0.1 wt% of the carbon.
  6. 6. The support or pre-catalyst of any one of claims 1 to 5, wherein the support or pre-catalyst comprises 1 to 11 wt%, 2.5 to 10wt%, 3 to 9 wt%, or 5 to 8 wt% of the water.
  7. 7. A chromium titanate/silica catalyst, the chromium titanate/silica catalyst comprising: Silicon dioxide; 0.1 to 5 wt% chromium, wherein at least 60 wt% of the chromium is present in the +6 oxidation state; 0.1 to 10% by weight of titanium, and An alkali metal in a bound state and/or zinc in a bound state; wherein the molar ratio of the combined alkali metal to the titanium and/or the combined zinc to the titanium is from 0.02:1 to 3:1, and/or Wherein the amount of said bound alkali metal and/or said bound zinc is in the range of 0.01mmol to 2mmol of said bound alkali metal or said bound zinc per gram of said silica.
  8. 8. The catalyst of claim 7, wherein the catalyst is characterized by a polymer having a HLMI (g/10 min) greater than equation Y (HLMI) = (-9.6153 x 3 + 21.088x 2 + 25.835x + 5.7983), where x is the number of titanium atoms per square nano-silica surface area of the chromium titanate/silica catalyst.
  9. 9. The catalyst of claim 7 or 8, wherein at least 70 wt%, at least 75 wt%, at least 80 wt%, at least 85 wt%, at least 90 wt%, or at least 95 wt% of the chromium is present in the +6 oxidation state.
  10. 10. The catalyst of any one of claims 7 to 9, wherein the catalyst comprises 0.3 wt% to 3 wt%, 0.4 wt% to 2 wt%, 0.5 wt% to 1.5 wt%, or 0.7 wt% to 1.5 wt% of the chromium.
  11. 11. The catalyst of any one of claims 7 to 10, wherein the catalyst further comprises less than or equal to 3 wt%, less than or equal to 2 wt%, less than or equal to 1.5 wt%, less than or equal to 1wt%, or less than or equal to 0.5 wt% water.
  12. 12. The support, pre-catalyst or catalyst of any one of the preceding claims, wherein the support, pre-catalyst or catalyst comprises 0.5 wt% to 7 wt%, 0.5 wt% to 3 wt%, 0.8 wt% to 2 wt%, 1wt% to 6 wt% or 1.5 wt% to 4 wt% of the titanium.
  13. 13. The support, pre-catalyst or catalyst of any one of the preceding claims, wherein the support, pre-catalyst or catalyst further comprises 0.01 wt% to 1.5 wt%, 0.1 wt% to 1.5 wt%, 0.3 wt% to 1 wt%, 0.4 wt% to 1.2 wt%, 0.4 wt% to 1 wt% or 0.5 wt% to 0.7 wt% nitrogen.
  14. 14. The support, pre-catalyst or catalyst of any one of the preceding claims, wherein the support, pre-catalyst or catalyst further comprises 0.005 wt% to 0.25 wt%, 0.01 wt% to 0.2wt%, 0.02 wt% to 0.25 wt%, 0.02 wt% to 0.2wt%, 0.02 wt% to 0.15 wt%, 0.02 wt% to 0.1 wt%, 0.03 wt% to 0.25 wt%, 0.03 wt% to 0.2wt%, 0.03 wt% to 0.15 wt% or 0.03 wt% to 0.1 wt% sulfur.
  15. 15. The support, pre-catalyst or catalyst of any one of the preceding claims, wherein the molar ratio of the bound alkali metal to the titanium or the bound zinc to the titanium is 0.08:1 to 3:1, 0.1:1 to 3:1, 0.12:1 to 3:1, 0.2:1 to 3:1, 0.02:1 to 2.5:1, 0.05:1 to 2.5:1, 0.12:1 to 2.5:1, 0.15:1 to 2.5:1, 0.05:1 to 2.2:1, 0.1:1 to 2.2:1, 0.2:1 to 2.2:1, 0.02:1 to 2:1, 0.05:1 to 2:1, 0.1:1 to 2:1, 0.12:1 to 2:1, 0.15:1 to 2:1, 0.2:1 to 2:1, 0.02:1 to 2:1, 0.8:1 to 2.8:1, 0.8:1 to 2:1, 0.8:1 to 2.2:1).
  16. 16. The support, pre-catalyst or catalyst of any of the preceding claims, wherein the amount of bound alkali metal or bound zinc is from 0.02 to 2, from 0.08 to 2, from 0.1 to 1, from 0.11 to 2, from 0.13 to 2, from 0.15 to 2, from 0.01 to 1.5, from 0.04 to 1.5, from 0.11 to 1.5, from 0.2 to 1.5, from 0.01 to 1.2, from 0.04 to 1.2, from 0.1 to 1.11 to 1.2, from 0.11 to 1.2, from 0.15 to 1.01 to 1, from 0.04 to 1, from 0.1 to 1, from 0.08 to 1, from 0.11 to 1, from 0.13 to 1, from 0.15 to 1, from 0.2 to 1, from 0.11 to 1, from 0.9 to 9, from 0.02 to 9, from 0.8 to 8, from 0.11 to 9 to 8, from 0.02 to 8, from 0.11 to 9, from 0.02 to 8, from 0.11 to 8, from 0.2.
  17. 17. The support, pre-catalyst or catalyst of any one of the preceding claims, wherein the support, pre-catalyst or catalyst comprises the bound alkali metal and the bound alkali metal comprises sodium.
  18. 18. The support, pre-catalyst or catalyst of claim 17, wherein: the titanium is adsorbed onto the silica; At least a portion of the sodium is bound to the titanium; at least a portion of the sodium is present as sodium titanate, or Any combination thereof.
  19. 19. The support, pre-catalyst or catalyst of any one of the preceding claims, wherein the support, pre-catalyst or catalyst comprises 70 wt% to 99.5 wt%, 80 wt% to 98 wt%, 80 wt% to 95 wt%, 85 wt% to 98 wt%, 85 wt% to 95 wt%, 90 wt% to 99.5 wt% or 90 wt% to 98 wt% of the silica.
  20. 20. A process for the polymerization of olefins comprising contacting the chromium titanate/silica catalyst of any one of claims 7 to 19 and optionally a cocatalyst with an olefin monomer and optionally an olefin comonomer in a polymerization reactor system under polymerization conditions to produce an olefin polymer.

Description

Aqueous process for titanating chromium/silica catalysts with alkali metals Citation of related application The present application was filed on 10/22 of 2024 as PCT international patent application and claims the benefits and priority of U.S. patent application nos. 18/780,704 (filed on 7/23 of 2024) and 18/492,911 (filed on 24 of 2023), the disclosures of which are incorporated herein by reference in their entirety. U.S. patent application Ser. No. 18/492,911 is a continuation of the section of co-pending U.S. patent application Ser. No. 18/306,326 filed on day 25 of 4 of 2023, U.S. patent application Ser. No. 18/306,326 claims the benefit of U.S. provisional patent application Ser. No. 63/334,741 filed on day 26 of 4 of 2022. Technical Field The present disclosure relates generally to chromium titanates, methods of preparing chromium titanates, methods of polymerizing olefins using chromium titanates, polymer resins produced using such chromium catalysts, and articles produced using these polymer resins. More specifically, the present disclosure relates to an aqueous process for preparing a chromium titanate catalyst, wherein an alkali metal is used during catalyst preparation. Background Chromium/silica catalysts can be used to produce HDPE. The addition of titanium to chromium/silica can increase the activity of the catalyst, but more importantly, can increase the melt index potential of the catalyst, i.e., the ability of the catalyst to produce higher melt index or higher melt flow polymers. Typically, the addition of titanium is accomplished by an anhydrous route, wherein a titanium precursor is used and impregnated onto the chromium/silica using a suitable organic solvent such as a hydrocarbon, alcohol or ether. Unfortunately, the presence of organics can lead to the emission of high Volatile Organic Compounds (VOCs) during the preparation, activation and processing of the chromium titanate catalyst. Water-based alternatives are available, but there are often problems of poor titanium efficiency and non-uniformity of incorporation. In view of these drawbacks, it would be beneficial to provide an improved process for preparing chromium titanate catalysts. The present invention is therefore generally directed towards this object. Disclosure of Invention This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter. This summary is not intended to limit the scope of the claimed subject matter. In one aspect of the invention, a titanated silica support is disclosed and in this aspect the titanated silica support may comprise silica, 0.1 to 10 wt% titanium, 0.5 to 12 wt% water, less than or equal to 2 wt% carbon and bound alkali metal and/or zinc, the molar ratio of alkali metal to titanium or zinc to titanium being in the range of 0.02:1 to 3:1 and/or the amount of alkali metal or zinc corresponding to each gram of silica being in the range of 0.01 to 2 mmol. In another aspect of the invention, a titanated chromium/silica pre-catalyst is disclosed and in this aspect may comprise silica, 0.1 to 5wt% chromium, 0.1 to 10 wt% titanium, 0.5 to 12 wt% water, less than or equal to 4 wt% carbon, and bound alkali metal and/or zinc, the molar ratio of alkali metal to titanium or zinc to titanium being in the range of 0.02:1 to 3:1 and/or the amount of alkali metal or zinc corresponding to each gram of silica being in the range of 0.01 to 2 mmol. In yet another aspect, a chromium titanate/silica catalyst is disclosed and in this aspect the chromium titanate/silica catalyst may comprise silica, 0.1 to 5 wt% chromium, 0.1 to 10 wt% titanium and bound alkali metal and/or zinc, the molar ratio of alkali metal to titanium or zinc to titanium being 0.02:1 to 3:1 and/or the amount of alkali metal or zinc corresponding to each gram of silica being in the range of 0.01 to 2mmol, wherein at least 60 wt% of the chromium is present in the +6 oxidation state. In yet another aspect, the chromium titanate/silica catalyst may comprise silica, 0.1 to 5 weight percent chromium, and 0.1 to 10 weight percent titanium, wherein at least 60 weight percent of the chromium is present in the +6 oxidation state, and the catalyst is characterized by a polymer having a HLMI (g/10 min) greater than the equation Y (HLMI) = (-9.6153 x 3+ 21.088x2 + 25.835x + 5.7983), wherein x is the number of titanium atoms per square nano-silica surface area of the chromium titanate/silica catalyst. The present invention also contemplates and encompasses olefin polymerization processes. Such methods may include contacting any (activated) chromium titanate/silica catalyst and optional cocatalyst disclosed herein with an olefin monomer and optional olefin comonomer in a polymerization reactor system under polymerization conditions to produce an olefin polymer. Advantageously, the titan