IP Library › Granted Patent US 12,623,207
Granted Patent B2
US 12,623,207 · App. 17/426,391 · Granted May 12, 2026

Process for the preparation of high surface area alpha alumina and the use thereof

Inventors: Amol Amrute (Mülheim an der Ruhr, DE); Ferdi Schueth (Mülheim an der Ruhr, DE); Hannah Schreyer (Mannheim, DE)
Assignee: STUDIENGESELLSCHAFT KOHLE MBH
B01J21/04B01J35/45B01J35/613B01J35/615B01J37/0036B01J37/082C01F7/441C01P2002/72C01P2002/88C01P2004/04C01P2004/64C01P2006/12
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Quick Facts
Patent No.
US 12,623,207
App. No.
17/426,391
Granted
May 12, 2026
Kind
B2
Abstract

The present invention refers to a process for the preparation of a high surface area nanoparticulate alpha alumina.

Claims (3)

1 . A method comprising:

(a) preparing a high-surface area nanoparticulate alpha alumina, having a BET surface area of at least 130 m 2 /g and having a particle size in the range of 1 to 50 nm measured by TEM, by a process comprising subjecting a precursor consisting of (A) γ-AlOOH·xH 2 O with x in the range of 0.1≤x≤0.5 and optionally (B) a metal and/or a metal compound to a milling process in a ball mill with a milling jar and balls in a weight ratio of balls to said γ-AlOOH·xH 2 O of 1 to 200 in a temperature range below the conversion temperature of nanocrystalline γ-AlOOH·xH 2 O to γ-Al 2 O 3 to yield said high-surface area nanoparticulate alpha alumina as a milling product; and

(b) using the high-surface area nanoparticulate alpha alumina prepared as catalyst or catalyst support for metal catalysts or in ceramics applications.

Assignments (2)
CHANGE OF NAME Recorded Feb 27, 2023
From: STUDIENGESELLSCHAFT KOHLE MBH
To: STUDIENGESELLSCHAFT KOHLE GGMBH
Reel/Frame 062876/0181 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jul 28, 2021
From: AMRUTE, AMOL; SCHUETH, FERDI; SCHREYER, HANNAH
To: STUDIENGESELLSCHAFT KOHLE MBH
Reel/Frame 057005/0727 →
Priority Claims (2)
EP 19154220 · Jan 29, 2019 · regional
DE 10 2019 216 426.9 · Oct 24, 2019 · national
Continuity (1)
Related Publication 20220088571A1 · Mar 24, 2022
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