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Oxford Catalysts Develops New FT Catalyst for Microchannel BTL Reactors

Oxford Catalysts’s OMX process produces a narrower particle size distribution of crystallites in the 8-15 nanometer diameter range which exhibit terraced surfaces—both features that enhance catalyst activity. Click to enlarge.

Oxford Catalysts has developed a new metal carbide Fischer-Tropsch (FT) catalyst designed for use in microchannel reactors targeted for the small-scale, distributed production of biomass-to-liquids (BTL) fuels. (Earlier post.) Microchannel systems with the new catalyst can be upwards of 20 times more productive per kilogram of catalyst than conventional systems, according to the company.

With approximately one tonne of biomass required to produce one barrel of liquid fuel, the transportation of biomass to a large-scale, centralized plant poses a challenge to the economics of biomass-to-liquids production. One approach being taken to address this is the development of small-scale Fischer-Tropsch reactors to convert the waste on a distributed basis locally rather than at large collection centers.

Microchannel reactors—compact reactors featuring channels with diameters in the millimeter range—are potentially the best candidates for this job. They enable more efficient and precise temperature control, and the small diameter channels dissipate heat more quickly than conventional reactors with larger channel diameters in the 20-30 mm (i.e. inch) range so more active catalysts can be used. As a result, microchannel reactors can exhibit conversion efficiencies in the range of 70% per pass.

Microchannel reactors are designed for economical production on a small scale. A single microchannel reactor block might produce up to 50 barrels (bbls) of liquid fuel/day. Conventional FT plants, in contrast, are designed to work at minimum capacities of 2,000 bbls/day, and function well and economically at capacities of 30,000 bbls/day or higher. They exhibit conversion efficiencies in the range of 50% or less per pass.

To work efficiently, microchannel reactors require an FT catalyst with a high level of activity in order to boost the conversion rates to an economic level. The new FT catalyst is designed to meet those requirements.

Commercial fixed bed FT reactors operate with a GHSV (Gas Hourly Space Velocity) of between 800 and 2,000 hr-1. GHSV is a measure of the feed flow rate relative to the volume of catalyst. These commercial fixed bed systems run to around 50% CO conversion per pass—mostly liquids and waxes but also some gases. They achieve this conversion at 230 - 240°C. By contrast, our catalyst in an FT microchannel reactor system can operate at GHSVs of over 24,000 hr-1 (well over an order of magnitude higher) and achieve a conversion per pass of over 70% at a temperature less than 220°C.

Since our catalyst in these microchannel systems are highly stable, the upshot is that these systems are over 20 times more productive per kg of catalyst than conventional systems. It is this higher productivity that will enable FT technology to be commercialized for small scale distributed biomass.

—Derek Atkinson, Business Development Director, Oxford Catalysts

The level of catalyst activity is related to the surface area of the catalyst. This, in turn, is related to crystal size, so producing catalysts with the optimal crystal size for a given application is a key goal for catalyst developers. One challenge is in achieving the right balance between catalyst activity and stability. If the crystal size is too large, the catalyst activity—and hence, conversion rates—will be reduced. If too small, the catalyst becomes unstable.

Oxford Catalysts’ organic matrix combustion (OMX) technology makes it possible to produce catalysts with higher metal loadings, which still maintaining small crystal sizes. The OMX method combines the metal salt and an organic component to make a complex that effectively stabilizes the metal. On calcination, combustion occurs that fixes the crystallites at this very small size. Since the calcination is quick, the metal crystallites do not have time to grow, and hence remain in the ideal size for catalytic reactions. The OMX crystallite size is independent of metal loading and support morphology, thereby producing more active FT catalysts with less metal.

The OMX method produces a crystallite size distribution 50% narrower than conventional Incipient Wetness Impregnation (IWI), leading to more active and stable FT catalysts. Click to enlarge.

Compared to conventional catalyst production methods, such as Incipient Wetness Impregnation (IWI), OMX produces a narrower particle size distribution of crystallites in the 8-15 nanometer diameter range which exhibit terraced surfaces. These are both features that enhance catalyst activity. OMX also produces fewer very small crystallites that could sinter at an early stage of operation. This results in greater catalyst stability. OMX catalysts also require less precious metal.

Following several thousands of hours of testing, Oxford Catalysts has signed a memorandum of understanding (MOU) with a leading developer of small scale FT microchannel reactors to deploy the new catalyst in small-scale FT applications, including the conversion of bio-waste or flare gas into liquid fuels.

We have spent 12 months working on developing this particular catalyst, using our state-of-the-art equipment and our patented OMX method, and are very pleased with the results. The next stage will involve working closely with a catalyst producer to supply tonnage quantities for use in demonstration units.

— Derek Atkinson



Now this is good news for the guys thinking in BtL direction. If they really demonstrate that the technology works on 50 bbl/day scale then this opens up a lot of opportunities.


" tonne of biomass required to produce one barrel of liquid fuel..."

Considering Syntec has over 100 gallons of alcohols per ton, this seems like a low number.


This is great since one of the things North Americans are the most productive at is creating tons of yard waste. Every local municipality could have a plant to process that local community’s yard waste; most already have the collection services built into the tax base already.


Regionaly dispersed production frees communities from mega economics. In the tradition of appropriate technology, locally applicable solutions enable diversity.
The most appropriate solutions may be electric battery/from wind, wave hydro, solar geo thermal biofuel, walking, sail, etc to the logical end.
While one size fits all, global energy, farming, transport solutions as we seem to locked into have evolved into fewer options.
Single solution strategies and reliance on solutions that in many instances are marginal in benefit relying on volume over efficiency encourages profiteering from wastefull and inefficient practices.(in my opinion.)

When small scale solutions are available the economics support market penetration, then we expect to see a decoupling from single market economies.

These indications signal a reversal from the last century of civilisation losing diversity and tying itself to the unwieldy behemoth that has as good as foundered in the current dilemma.

As with *religion, culture, microsoft,* there is no compelling reason why free thinking people should accept the total package, all or nothing option.
Pick and choose mix and match = more choice.

Any technology that supports small scale independent operations is gold.


No mention of fouling by tar at these lower temperatures or problems with chlorine compounds like PVC plastic. Even if the XTL plant can be made smaller it still has to have affordable capital cost. For small communities that means less than a few million dollars. Otherwise the aim should be simple gasification not liquids.


Call me old fashioned, but I am glad that this will help keep Incipient Wetness Impregnation out of my neighborhood.
As arnold so succinctly put it, small size and diversification is golden for nascent industries.



Remember that with F-T we are talking about hydrocarbons not alcohols. Hydrocarbons have a heating value of about 44 MJ/kg while lower alcohols like methanol or ethanol only half that value. What really shows the conversion efficiency is how much of the biomass energy is converted into liquid fuel energy. For biomass gasification/F-T route this is about 40 to 50%. I don't think that any other route be it hydrolysis/fermentation or gasification/syngas fermentation has any higher efficiency.


Tar and chlorine are going to be bad for any catalyst. These have to be removed before the synthesis step. The content of these impurities in the synthesis gas is going to depend on the gasification system and the feedstock. What these guys have really demonstrated is that you can do F-T synthesis on a 50 bbl/day scale. However, the old German F-T plants had only slightly higher capacities. A single F-T reactor in these plants produced about 25 bbl per day of liquids from 1000 m3 of syngas per hour; usually these plants had 24 reactors or so. Each of these reactors weighed about 50 tons and contained 12 m3 of Co catalyst. The weight of cobalt was 1 ton.

Henry Gibson

Hydrothermal processing to a hydrocarbon liquid, as mentioned in another article, could produce a liquid that is used as fuel or saved in a tank that is shipped for refining later into diesel or gasoline. ..HG..


If you can get 42 gallons per ton of gasoline at 125k BTUs per gallon (42 x 125,000 = 5,250,000 BTUs) or 100 gallons of ethanol at 76k BTUs (100 x 76000 = 7,600,000 BTUs), it seems like making alcohol is more efficient at turning one ton of biomass into more most BTUs.

Amitava Banerji

Dr.Atkinson's work on FT process in micro-channel reactor seems to hold promise for a country like India, where I practise project design and engineering consultancy in areas of Chemcial & Process Engineering.

Having been involved with the design of a pilot-plant for GTL using producer gas from gassification of wood to produce liquid hydrocarbon by the FT process, I have been wondering if this process can be extended to producer gas from a certain bio-mass which has a lower hydrogen to CO ratio. This bio-mass has a low bulk density and is abanduntly available all across India. As rightly indicated in the article by Dr.Atkinson, the viability for setting up small plants in every village to produce liquid fuel from the bio-mass that is locally available within an affordable distance from the village should be established.
The answer that I am looking forward to get and this is where I would request Dr.Atkinson to give me a response: what is the lowest H2 to CO ratio that his process can work with? At what stage of development is this process?

It will be a pleasure to get a response from Dr.Atkinson or any of his colleagues working on this Project.


Amitava Banerji

village guy

Hi Amitava,

I am not from Atkinson's team, but anyway: do you think that downdraft producer gas with high nitrogen content is a suitable feedstock for F-T synthesis? I have not yet seen published data on F-T synthesis using producer gas.
I think that conversion per pass would be too low to get a reasonable biomass-to-liquids conversion efficiency i.e. most of the energy of the producer gas will still be in the reactor tail gas. Also, you would have to clean large volumes of gas for the synthesis step, but get only a little bit of liquids.
I think that an externally heated gasifier concept is better suited for BtL. This will give nitrogen free gas with equilibrium CO to H2 to CO2 ratio. CO to H2 can easily be set to 2.

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