R&D Activities ● Inorganic Membranes Research Center

RITE Today 2022

Inorganic Membranes Research Center
Members (As of Dec. 2021)
Shin-ichi Nakao, Director of the Center, Chief Researcher
Kumiko Konishi, Deputy-Director, Chief Researcher
Hidetoshi Kita, Chief Researcher
Masahiro Seshimo, Senior Researcher
Kazuyuki Kitamura, Senior Researcher
Makoto Ryoji, Senior Researcher
Fuminori Ito, Researcher
Lie Meng, Researcher

Hiromi Urai, Research AssistantYuko Nara, Research AssistantKazuaki Sasa, Research AssistantNobuaki Oono, Research AssistantChiyoko Shindo, Research Assistant
Akiyoshi Fujii, Research AssistantKeiko Komono, Research AssistantResearch and Development of Innovative Environmental and Energy
Technologies that Use Inorganic Membranes and Efforts for Practical
Use and Industrialization
1. Introduction
The Paris Agreement began full-scale operation in

be an innovative technology that greatly contributes tothe reduction of greenhouse gas emissions.

2020, and in October, 2050 Carbon Neutral was de-

The Inorganic Membrane Research Center (IMeRC)

clared in Japan as well. In order to achieve this goal, itaims for the early practical use and industrialization ofis necessary to effectively reduce greenhouse gas emis-

innovative environmental and energy-saving technolo-

sions and realize carbon recycling that utilizes CO 2 as agies using inorganic membranes. The organization isresource.

composed of two departments, the Research Depart-

Inorganic membranes of silica, zeolite, and palladium

ment and the Industrial Cooperation Department, in or-

have the features of excellent mechanical strength andder to promote activities with research and develop-

heat and chemical resistance compared to polymer

ment and industrial collaboration.

membranes. In addition, by using a membrane reactor

In the Research Department, membrane reactors forthat uses the inorganic membrane, energy consump-carbon capture and utilization (CCU) are developed us-

tion is significantly reduced compared to conventionaling silica, zeolite, and palladium membranes, whichpacked-bed reactors that require separation and purifi-

have unique characteristics, respectively. We mainly de-cation processes of distillation and adsorption. It also

velop two-types of membrane reactors for synthesis of

has the potential to simplify the process. Based on thesemethanol and liquid hydrocarbon fuel via captured CO2.

excellent characters of inorganic membranes, as a tech-

In the case of liquid hydrocarbon fuel, CO2 directly cap-

nology that can realize an innovative production pro-tured from the air is the raw material. In addition, we arecess, research is underway on the application of thealso conducting research on hydrogen production by

membranes as an alternative to distillation and the ef-

direct decomposition of methane for the purpose offective use of captured CO2. Furthermore, the develop-

CO2-free and low-cost hydrogen production.

ment of hydrogen permselective membranes for CO2-

In the Industrial Collaboration Department, the In-

free and low-cost hydrogen production, which is indis-

dustrialization Strategy Council, which consists of 18

pensable for building a hydrogen society, is expected to58

R&D Activities ● Inorganic Membranes Research Center

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companies of inorganic membrane and porous-sub-

Adopted as a contract project of NEDO in FY 2019,

strate manufacturers and user companies, aims to sharethe objective was follows: a) development of a high hy-

the vision among manufacturers and user companies bydrogen permselective membrane with durability underplanning joint research. Member companies have regu-

high temperature conditions (>500°C), b) development

lar opportunities to share ideas and promote activities

of a catalyst that activates at relatively low reaction tem-through study groups.

peratures for the membrane reactor, and c) the devel-

This paper introduces the main achievements and fu-

opment of membrane reactors consisting of a hydrogenture prospects of the research division, such as CCU

separation membrane and a catalyst with a demonstra-technology development and hydrogen production

tion of their effectiveness. (Fig. 2)

from methane, and the status of the activities of the Industrialization Strategy Council.

Fig. 2 Application of a membrane reactor to the hydrogenproduction process from methane decomposition

For the development of a hydrogen permselective
Fig. 1 Promotion system of IMReC

membrane in a), silica and palladium membranes are
candidates. We have succeeded in developing a hydro-

2. Development of CO2-free hydrogen production tech-

gen permselective membrane having high H2 perme-

nology from methane decomposition

ance and heat resistance at 723 K. Both of the silica andTo realize a society that relies on hydrogen, a method

palladium membranes were showed over 5 x 10-7 molis required to produce hydrogen at low cost and in large

m-2 s-1 Pa-1 of H2 permeance, and 3,000 of H2 selectivity.

quantities. With the focus on methane, which can be

These results were exceeded the final goal of this pro-stably supplied for a long time because of the shale gas

ject. In addition, Ni/Fe/Al2O3 as a catalyst for methane

revolution, hydrogen and solid carbon are produced bydecomposition showed relatively high catalytic activity

pyrolysis, and hydrogen production costs can be re-at 873 K.

duced by selling the carbon. A membrane reactor,

We calculated the hydrogen production efficiency

which is applied to that reaction, could produce hydro-

and CO2 emissions using a membrane reactor for me-

gen at low cost and save on energy consumption. In ad-

thane decomposition. As shown in Fig. 3, high hydrogendition, the process has the advantage of not emitting

production efficiency and low CO2 emissions were ob-

carbon dioxide and is a technological development thattained compared with the conventional packed bed re-contributes to a decarbonized society.

actor (PBR). Compared with the CO2 emissions from the59

R&D Activities ● Inorganic Membranes Research Center

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methane steam reforming (SRM), which is a general hy-

membrane reactor showed 0.8 (palladium membrane),drogen production method, CO2 emissions from SRM

and 0.7 (silica membrane) at 873 K as the reaction tem-are 0.95 kg-CO2/Nm -H2, whereas methane decompo-

perature and 0.4 MPa as the reaction pressure. Com-sition using the membrane reactor is 0.2 kg-CO2/Nm3-

pared to a packed bed reactor, both membrane reactors

H2. The CO2 emissions from this membrane reactor canobtained higher methane conversion. On the otherbe suppressed to about 1/5.

hand, in the case of a reaction temperature of 773 K,

3

methane conversion using a membrane reactor was approximately the same as when using a packed bed reactor. It is assumed that the Ni/Fe/Al2O3 catalyst
showed low catalytic activity at 773 K. Thus, these results propose that the development of a catalyst having
higher catalytic activity in lower reaction temperatures
is indispensable. This is one of the major issues in thedevelopment of membrane reactors using inorganic
membranes and is not limited to methane decomposition. In the future, the research and development of amembrane reactor should be promoted by integrating
catalyst development and membrane development.

Fig. 3 Calculation results of effect to apply the membranereactor for methane decomposition.
a) Hydrogen production efficiency, b) CO2 emission.

Fig. 4 shows results of the membrane reactor tests
using palladium and silica membranes as hydrogenpermselective membranes. A broken line in this figure

Fig. 4 Effect of methane conversion increasing using membrane reactor.

shows methane conversion using the packed bed reactor, and a solid line shows the maximum methane con-

3. CO2 utilization technologies in RITE

version theoretically obtained using the membrane re-

Recently, CO2 utilization technologies have been ac-

actor. From these results, methane conversion using thetively researched and developed in countries around60

R&D Activities ● Inorganic Membranes Research Center

RITE Today 2022

the world, including the EU, as being effective in reduc-

pected to be one of the highly efficient methanol pro-ing CO2 emissions. On the other hand, in the hydro-

duction processes.

genation of CO2, water is generated by the reaction,

At the RITE Inorganic Membranes Research Center,

which decreases the reaction rate. In addition, most re-we successfully developed a novel hydrophilic zeolite

actions are exothermic, and the removal of the reaction

membrane, which has higher hydrothermal stability andheat is one of the problems. In order to solve thesewater/methanol permselectivity compared to the con-problems, highly efficient, energy-saving CO2 utilization

ventional LTA-type zeolite membrane. This membrane

technology has been developed at the Inorganic Mem-

was applied to the membrane reactor for methanol syn-branes Research Center using a membrane reactor.

thesis, and CO2 conversion was achieved at a rate threetimes higher compared to the conventional packed-bed

3.1. Development of effective methanol synthesis fromreactor at a reaction temperature of 473 K and a reac-

CO2 hydrogenation

tion pressure of 4 MPa.

Methanol is an important intermediate for chemical

In near future, we will improve dehydration zeolite

products, and demand is expected to grow in the future.

membrane performance, and produce a membrane

Methanol is mainly synthesized using syn-gas (mixture

having a higher effective membrane area. A new projectgases of CO and H2); however, synthesis requires highfor that purpose was adopted in 2021.

temperatures and high pressures. Generally, Cu/ZnObased catalysts are used with the reaction within the

3.2. Development of liquid hydrocarbon fuel synthesis

temperature range of 473–573 K. On the other hand,

technology using CO2 as a raw material captured fromthe one-pass yield shows low values owing to equilib-

the airrium limitations. This is remarkable in the methanol syn-

Liquid hydrocarbon fuels by recycling CO2 throughthesis from CO2 hydrogenation represented by the fol-the existing infrastructures for transportation and stor-

lowing reaction formula.

age have a lower cost than new fuels, so they should be

CO2 + 3H2 ⇄ CH3OH (methanol) + H2O

established to achieve carbon neutrality. The NEDO
project Moonshot Research & Development Program

CO2 emission reduction potential can be expected at

was adopted in collaboration with Kanazawa University

about 100 million tons/year (assuming demand metha-and the RITE Chemical Research Group in 2020. At thenol production of 50 million tons/year) when methanol

IMeRC, we accepted the challenge of developing the

production process will change to that via CO2 as thetechnology to convert the captured CO2 into liquid hy-

raw material. Thus, highly efficient methanol synthesis

drocarbon fuel by FT (Fischer-Tropsch) synthesis (Fig. 5).

processes from CO2 have been required. If the produced

Similar to methanol synthesis, the water produced fromwater is removed from the methanol synthesis reaction

the reaction causes catalyst deactivation and a reaction

system, it can be improved to a one-pass yield with syn-rate reduction in FT synthesis. Another problem is thethesized methanol at a relatively mild condition of lower

difficult reaction control for liquid fuel because thereaction pressure and temperature. The membrane re-product followed the ASF (Anderson-Schulz-Flory) dis-

actor with the water permselective membrane is ex-

tribution.

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R&D Activities ● Inorganic Membranes Research Center

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Fig. 5 Overview of the Moonshot project at RITE

Therefore, in this project, we will develop high effi-

The membrane reactor for FT synthesis was designed

ciency, energy-saving CO2 utilization technology fromand will be put into operation. A simulation model was

the CO2 captured from the air as the raw material for

constructed prior to the experiments, and it was con-the membrane reactor. Research and development

firmed that the membrane reactor can obtain a higher

items are as follows.

CO2 conversion rate than the conventional catalyst-a) Development of membranes applicable to FT syn-packed bed reactor.

thesisb) Development of a membrane reactor for FT synthesisc) Search for the optimal process structure

In the future, we will make the best use of theknowledge we acquired and strongly promote the development of inorganic membranes and membrane reactors applicable to FT synthesis. We then intend to unravel the science of inorganic membranes that we have

The target membranes are hydrophilic membranes

left unattended.

and hydrogen permselective membranes. Catalyst deactivation can be suppressed if the generated water can

4. Activities and efforts toward commercialization andbe removed from the reaction side by using a hydro-

industrialization

philic membrane, such as zeolite. Furthermore, the re-

The core of the Industrial Collaboration Department

action can be controlled by supplying H2 to the reactionof the IMeRC is the Industrialization Strategy Council. A

field via hydrogen permselective membranes, such as

total of 18 separation membrane and support manufac-

silica and palladium. We succeeded in developing theturers and user companies (as of January 2022) partici-

Si-rich LTA-type zeolite membrane with improved hy-

pate on this council. Our goal is to establish an inorganic

drothermal stability compared to the conventional LTA-

membrane industry that contributes to innovative envi-

type zeolite membrane. We are also involved in the de-ronmental and energy technologies by promoting avelopment of silica membranes with excellent hydrogencommon vision for manufacturers and user companies,

permselectivity.

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R&D Activities ● Inorganic Membranes Research Centeras well as a joint research plan involving national projects and other initiatives.
We are promoting a variety of activities, which include
the following:

RITE Today 2022

We also held a seminar for council members online.
There were lectures from universities, member companies, membrane-related companies, etc. on the latest R& D trends and introduction of needs, seeds, practicala) Sponsoring needs and seeds matching meetings

development cases of membranes, and lively questions,

toward the practical use of innovative environmen-

answer. In addition, we conduct patent and literature

tal and energy technologies that use inorganic

searches related to the content of the lecture, and reg-

membranes, and the establishment and operation

ularly provide members with needs seeds informationof a research group that will prepare the futurewith comments from the IMeRC in the summary.

roadmapb) Planning joint implementation projects funded by
the government and NEDO

5. In conclusion
In November 2021, the Inorganic Membrane Envi-c) Acceptance of researchers from council membersronment and Energy Technology Symposium to Explore

to the Research Section of the IMeRC and the im-

the Future was held online for the first time in two years

plementation of training workshopswith the attendance of 389 people. At this symposium,d) Offering technical guidance from the IMeRC Advi-

under the theme of carbon recycling, universities andsory Board and Research Section

companies gave lectures on the latest trends in CO 2e) Hosting exclusive technology seminars for council

separation / recovery / effective utilization, carbon cycle

membersf) Offering exclusive supply services (Needs and Seeds
Technology Information) to council members

technology and efforts toward practical application. We
introduced the latest research results of the IMeRC andthe efforts of the Industrialization Strategy Council.
The audience commented that they were able toIn 2021, because of the spread of the COVID-19 virus,

deepen their understanding of carbon recycling, as well

we had to refrain from face-to-face activities, but we ac-

as understand the specific efforts toward practical use

tively promoted study group activities and seminars us-

and the effectiveness of inorganic membranes in sepa-

ing the Web.

ration technology.

Two study groups, the Membrane Reaction Process

The need for innovative environmental and energy

Study Group and the Common Infrastructure (Perfor-

technology development that contributes to decarbon-

mance Evaluation) Study Group, have started new stud-ization is increasing toward 2050 carbon neutrality. As

ies. The Membrane Reaction Process Study Group ex-

the IMeRC, we would like to deepen basic and appliedamined a computational platform that enables compar-

research that makes the best use of the advantages of

ative studies of performance, energy balance, and cost,

inorganic membranes, and accelerate the movement

which are indispensable for social implementation of

toward social implementation

membrane reactors. The Common Infrastructure (Performance Evaluation) Study Group conducted a basic
study toward standardization of separation membrane
performance evaluation methods with the aim of promoting the industrialization of inorganic membranes.

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