Method for quantitative analysis of hydrogen in porous silica

Patent metadata

Field	Value
Publication number	US-12025554-B2
Application number	US-201916631706-A
Country	US
Kind code	B2
Filing date	Jan 16, 2019
Priority date	Jan 19, 2018
Publication date	Jul 2, 2024
Grant date	Jul 2, 2024

Abstract

A method for quantitative analysis of hydrogen gas generated due to the decomposition of Si—OH (silanol) in porous silica, which is a support of a metallocene catalyst is provided. The analysis enables the measurement of the content of hydrogen present in trace amounts in silica by employing an inert gas fusion-infrared absorption (IGFIA) method under specific pressure and temperature conditions.

First claim

What is claimed is:

1. A method for quantitative analysis of hydrogen in porous silica, comprising:
(i) heating porous silica used in a production of metallocene polypropylene catalyst at 0.1 bars to 0.15 bars and at 550° C. to less than 700° C. for 60 seconds to 1.5 minutes to evaporate moisture, and then adsorbing the evaporated moisture on a moisture scrubber to remove the adsorbed moisture, and
(ii) heating the porous silica from which moisture has been removed at 0.1 bar to 0.15 bars and at 1200° C. to 1300° C. for 60 seconds to 1.5 minutes to decompose a Si—OH group, resulting in hydrogen gas, and then transferring the hydrogen gas to an infrared detector using a carrier gas to quantitatively analyze hydrogen using an inert gas fusion-infrared absorption (IGFIA) method
wherein the porous silica has an average particle size of 30 μm to 55 μm and a BET surface area of 300 m 2 /g to 350 m 2 /g,
wherein the porous silica includes hydrogen in an amount ranging from 100 mg/kg to 1000 mg/kg.

2. The method according to claim 1 , wherein (1) the heating is carried out at 0.102 bars to 0.104 bars and at 590° C. to 650° C. for 70 seconds to 1.2 minutes.

3. The method according to claim 1 , wherein (1) the heating is carried out at 0.1 bars and at 600° C. to 610° C. for 90 seconds.

4. The method according to claim 1 , wherein (ii) the heating is carried out at 0.102 bars to 0.104 bars and at 1230° C. to 1260° C. for 70 seconds to 1.2 minutes and wherein the carrier gas is helium (He) gas.

5. The method according to claim 1 , wherein (ii) the heating is carried out at 0.1 bars and at 1250° C. for 90 seconds.

Assignees

• Lg Chemical Ltd

Inventors

• Na Sumin
• Kim Jieun
• Shin Sunah
• Jung Min Hwan

Classifications

• G01N1/44

  Sample treatment involving radiation, e.g. heat · CPC title

• G01N2001/4027

  evaporation leaving a concentrated sample · CPC title

• G01N33/005

  H2 · CPC title

• C01P2006/12

  Surface area · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title