Novel pretreatment for Cellulosic Bio-Ethanol production “Glycerol Bio-refinery process”

Leaf Energy closer to patent grant for Bio-Ethanol production process

The Directors of Leaf Energy would like to advise shareholders that patent applications for the novel pretreatment of Cellulosic Biomass for Bio-Ethanol production are due for Patent Cooperation Treaty publication on the 6th December 2012.

Patent development and rights
The patent application titled “Methods for Converting Lignocellulosic Material to Useful Products” (“Glycerol Bio-refinery process”) describes the process developed at the Queensland University of Technology (QUT) by Zhanging Zhang, Ian O’Hara and William Doherty.

The production of biofuels from waste agricultural biomass requires an integrated process that starts with the breakdown of the fibre (pretreatment), conversion of the pretreated fibre into sugars and the subsequent production of ethanol and co-products. There are several pretreatment processes that are effective at breaking down fibre, but most require high temperatures, resulting in high-energy use and the production of sugar degradation compounds that inhibit the subsequent fermentation. In many pretreatment processes, the chemicals used are expensive.

The “Glycerol Bio-refinery Process” overcomes these problems by being effective at much lower temperatures than other benchmark pretreatments. At these lower temperatures, energy use is reduced and losses of sugars to degradation products are greatly reduced. Glycerol production has increased rapidly around the world as a waste product from biodiesel production and is a low cost chemical to use in pretreatment.

Data published in the patent specification for the “Glycerol Bio-refinery Process” shows that after 24 hours this process has liberated over 90% of the digestible cellulose (see graph next page).

Leaf Energy has recently been advised these results have been successfully repeated at pilot scale, at the Mackay Renewable Bio-commodities Pilot Plant operated by QUT.

Similar enzymatic digestibility outcomes were achieved in the pilot scale trials as was achieved at the laboratory scale despite less severe pretreatment conditions (lower amounts of acid, lower pretreatment temperatures, shorter pretreatment times and higher water content) being used.
The ability of the process to limit fermentation inhibitory products was also repeated at the pilot scale.

Pilot trials to date have been conducted on waste sugar cane also known as bagasse. However the patent applications apply to any potential lignocellulosic feedstock.

Leaf Energy rights
The patent applications for the “Glycerol Bio-refinery Process” are part of the joint IP developed under the Collaboration and License Agreement executed between Leaf Energy, Syngenta, QUT, and QUTBluebox. Leaf Energy has rights to these patents in Australasia.

Leaf Energy is also in the process of obtaining rights to the IP in India, Thailand, the Philippines, Nicaragua, Guatemala, Mauritius, Malaysia and Indonesia.

Potential benefits of the technology are:

  • Highly effective pre-treatment delivering 90% of the available digestible cellulose,
  • Glycerol is a low cost industrial chemical that is a much used and widely available.
  • Glycerol is non-toxic and biodegradable
  • Non recycled glycerol outputs from the process can be additionally converted to ethanol or other products
  • The process enables more efficient enzymatic hydrolysis

The benefits described above positively influence the economic outcomes in the production of cellulosic ethanol from waste bio-mass. In addition, the lower temperatures and pressures under which the “Glycerol Bio-refinery Process” operates may lead to lower capital costs and the potential to retrofit the technology to existing cellulosic ethanol and standard ethanol plants.

No competition with food and carbon benefits
The use of waste cellulosic feedstock’s such as bagasse means that there is no competition with food requirements or land used for food production. This is a significant drawback with other feedstock’s.

The production of ethanol from waste cellulosic biomass also has major carbon benefits: Reductions of 70% to 86% have been estimated for cellulosic ethanol use in comparison to standard fuels.

Second Generation Biofuel Developments
The development of second-generation biofuels is progressing at a rapid rate particularly in North and South America but also Asia and Europe. Major stakeholders that are taking positions include; the major fuel companies (BP, Chevron, Shell etc.), the major agricultural biotechnology companies (Monsanto, Syngenta, Bayer, DuPont), feedstock innovation companies (e.g. Ceres, Mendel) and major enzyme manufacturers (Novozymes, DSM).

This situation is also evident in Australia with Mitr Pohl’s takeover of MSF Sugar (Maryborough) with the stated intention of investing in bio-energy.

Governments throughout the world are also supporting the development of second-generation biofuels. In the USA government support (US Departments of Energy and Defense) is continuing to rapidly advance the development of the industry as a way of overcoming the political uncertainty that still exist in the supply of energy throughout the world. The USA is one of many countries seeking greater energy independence to mitigate this uncertainty.

Energy shortfall and demand
The potential energy shortfall is another driver of the developments in cellulosic energy. Cambridge Energy Research has identified that the energy shortfall will reach the equivalent of 35 billion barrels of oil per day by 2030 and have also predicted that the shortfall can’t be filled by fossil fuels.
Many experts see cellulosic bioenergy is a part of the solution. Cellulose is the most abundant organic material on earth and the use of waste cellulose doesn’t exacerbate the feedstock “bubble” as waste biomass avoids the food/fuel conflict. It also has the benefit of less volatile pricing and importantly produces a liquid transport fuel that is renewable and carbon friendly.

The commercialization of second-generation biofuels has also been assisted by the continuing fall in enzyme prices. Recently the large enzyme companies have announced significant falls (claims of up to 50%) in the price of relevant enzyme. Much development is continuing in this field.

While the technology is developing rapidly elsewhere, there appear to have been no attempts to produce anything more than laboratory scale cellulosic ethanol in Australia. As a result, cellulosic ethanol has a low profile in Australia, even though in Queensland a large supply of one of the better cellulosic ethanol feed stocks, sugarcane bagasse is available. In Australia governments are also very supportive with a number of initiatives aiming to assist the development of the alternative fuels industry generally and also cellulosic biofuels.

Potential of the Bio-ethanol market
Australians spend about $50 billion on energy each year and 35% of that amount is related to transportation costs. Sugarcane bagasse has the potential to provide sufficient ethanol for 14% of Australia’s automotive gasoline requirement and the market in QLD and NSW alone is enough for 1,000 megalitres, a $700 million market.

E10 is a very popular fuel in NSW with 40% of the market. If there was a 10% ethanol mandate across Australia that would equate to a 2,000 megalitre,$1,400 million market.

Australia’s first major cellulosic Ethanol production project
Leaf Energy is working towards the first major Cellulosic Ethanol production project in Australia. It will be a significant opportunity to profile the groundbreaking “Glycerol Bio-refinery Process” in a pilot scale demonstration of cellulosic ethanol production from sugarcane bagasse. To our knowledge this will be the first major pilot scale production of any second generation biofuel in Australia.

Through this demonstration Leaf Energy should establish sufficient data to progress the technology to a point where it can be licensed and integrated into cellulosic ethanol plants in Australasia and other regions of the world where we have patent/licence coverage.

Ken Richards
Managing Director
Phone: 0403 385 051

Jay Hetzel
Phone: 0413 045 478


Leaf Energy, press release, 2012-11-16.


Cambridge Energy Research
Leaf Energy
Queensland University of Technology (QUT)


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