公开(公告)号：US20230356153A1

公开(公告)日：2023-11-09

申请号：US18352377

申请日：2023-07-14

Applicant: NGK INSULATORS, LTD.

Inventor： Aya MIURA ,  Narumi TOMOKAGE ,  Azumi OTA ,  Katsuya SHIMIZU

IPC: B01D65/02 ,  B01D71/02 ,  B01D69/02

CPC classification number: B01D65/02 ,  B01D71/0281 ,  B01D69/02 ,  B01D2325/12 ,  B01D2323/081 ,  B01D2321/32

Abstract: A membrane heat treatment method includes a process of raising the temperature of a membrane to an intermediate heating temperature (step S21), a process of heating and keeping the membrane at the intermediate heating temperature (step S22), a process of raising the temperature of the membrane to a main heating temperature higher than the intermediate heating temperature (step S23), and the process of heating and keeping the membrane at the main heating temperature (step S24). A first recovery amount R1 that is a difference in permeability of the membrane between after step S22 and before step S21 is 50% or more and 95% or less of a second recovery amount R2 that is a difference in permeability of the membrane between after step S24 and before step S21.