Process for making molecular sieves

Patent metadata

Field	Value
Publication number	US-11111153-B2
Application number	US-201916545079-A
Country	US
Kind code	B2
Filing date	Aug 20, 2019
Priority date	Aug 27, 2018
Publication date	Sep 7, 2021
Grant date	Sep 7, 2021

Abstract

Processes are provided for preparing molecular sieves for use as catalysts. The process involves preparing a synthesis mixture for the molecular sieve wherein the synthesis mixture includes a morphology modifier which may be selected from cationic surfactants having a single quaternary ammonium group comprising at least one hydrocarbyl group having at least 12 carbon atoms, nonionic surfactants, anionic surfactants, sugars, and combinations thereof.

First claim

The invention claimed is:

1. A process of preparing crystals of a molecular sieve, the process comprising the steps of:
a. combining at least a source of a tetravalent element X, a morphology modifier L, and water to form a synthesis mixture;
b. heating said synthesis mixture under crystallization conditions for a time of about 1 hour to 100 days to form the crystals of the molecular sieve; and
c. recovering said crystals of the molecular sieve from the synthesis mixture;
wherein the morphology modifier L is selected from the group consisting of cationic surfactants having a single quaternary ammonium group comprising at least one hydrocarbyl group having at least 12 carbon atoms, and is present in the synthesis mixture before nucleation or crystallization of the crystals begins;
wherein if the molecular sieve is one which requires a structure directing agent Q, the morphology modifier L is different from and is present in addition to the structure directing agent Q;
wherein the molar ratio L:X in the synthesis mixture is in the range of from 0.0001 to 0.03; and
wherein the synthesis mixture is a liquid that is substantially a single phase, or a mixture of solid and a liquid that is substantially a single phase is substantially a single phase;
and wherein the molecular sieve has a framework structure selected from the group consisting of MRE, MWW, MTW, FAU, EMT, MFS, MEI, BEA and its polymorphs, TON and MTT.

2. A process as claimed in claim 1 , wherein in step a) one or more further components selected from the group consisting of a source of hydroxide ions, a structure directing agent Q, a source of a trivalent element Y, a source of a pentavalent element Z, a source of halide ions W − , and a source of alkali metal ions M + and/or alkaline earth metal cations M 2+ , are also combined into the synthesis mixture.

3. A process as claimed in claim 1 wherein X is selected from Si, Ge and mixtures thereof and the synthesis mixture also comprises a source of a trivalent element Y, where Y is selected from Al, B, Ga, Zn and mixtures thereof.

4. A process as claimed in claim 3 wherein X=Si and Y=Al.

5. A process as claimed in claim 1 in which the molar ratio L:X in the synthesis mixture is in the range of from 0.001 to 0.025.

6. A process as claimed in claim 1 in which the morphology modifier L is a cationic surfactant having the formula (1)
(R 1 ) q (R 2 ) 4-q N + (X n- ) 1/n   (1)

wherein each R 1 is independently a C 1 -C 6 , optionally a C 1 to C 4 , alkyl group which may be linear or branched, saturated or unsaturated; R 2 is a C 12 to C 30 ; q is 1 or 2; X − is an anion of valency n; and X − is a hydroxide anion or a halide anion selected from fluoride, chloride or bromide.

7. A process as claimed in claim 1 which includes the step of calcining the crystals recovered in step c) to give the calcined form of the molecular sieve.

Assignees

• Exxonmobil Res & Eng Co

Inventors

• Kamakoti Preeti
• Weigel Scott J
• Strohmaier Karl G
• Jaensch Helge
• Anthonis Marc H
• Dictus Martine
• Engels Brita
• Lacy Darryl D
• Sartipi Sina

Classifications

• C01B39/48 Primary

  using at least one organic template directing agent · CPC title

• C10G35/095

  containing crystalline alumino-silicates, e.g. molecular sieves {(C10G35/065 takes precedence)} · CPC title

• B01J29/7034

  MTW-type, e.g. ZSM-12, NU-13, TPZ-12 or Theta-3 · CPC title

• B01J29/041

  Mesoporous materials having base exchange properties, e.g. Si/Al-MCM-41 · CPC title

• B01J29/7007

  Zeolite Beta · CPC title