• Catalytic Fast Pyrolysis of wood to the key aromatic compounds, Benzene, Toluene, and Xylene (BTX), with generation of paraxylene from the BTX and subsequent conversion to purified terephthalic acid (PTA) and polyethylene terephthalate ( PET).
• Gasification of woody biomass to syngas with subsequent synthesis of methanol, plus methanol to propylene and polymerization to polypropylene.
• Enzymatic hydrolysis of wood to ethanol, with subsequent catalytic dehydration to ethylene and production of high density polyethylene (HDPE).
• Cellulosic plastics pioneered by Eastman (Tenite™ Cellulosics), which find commercial application in tool handles, toothbrushes, golf putters, alternatives to urethanes, etc.
These are compared to traditional fossil-fuel-based routes.
Technology Analysis
Catalytic Fast Pyrolysis to PET (Tree-Based PET)
Anellotech's innovative Catalytic Fast Pyrolysis technology and subsequent processing to produce a renewable, wood-based paraxylene ( p-X), from which tree-based purified terephthalic acid (PTA) is synthesized; PTA is a key ingredient (along with monoethylene glycol) used to make PET:
The tree-based process only differs from the conventional petroleum-based process in the first step, using the CFP™ process to generate the BTX from trees, instead of from petroleum-based naphtha at an oil refinery.
Gasification to Polypropylene (Tree-Based Propylene)
Gasification of woody feedstock generates syngas, which is subsequently converted to methanol via the well-known Methanol-to-Propylene (MTP™) process, and polymerization of the propylene to polyolefin, as shown below:
This process has multiple steps but is rather straightforward, with each of the technologies having been proven commercially.
Enzymatic Hydrolysis in SSF to HDPE (Tree-Based HDPE)
The simultaneous saccharification and fermentation (SSF) of wood chips to ethanol using enzymatic hydrolysis to generate sugars from wood chip feedstock is followed by the dehydration of ethanol to ethylene, which is subsequently polymerized to HDPE.
The pathway assessed here begins with technologies that have been long studied to extract sugars from cellulosic feedstock. The subsequent processes to ferment those sugars to ethanol, from which ethylene and HDPE are derived, are in practice commercially around the world.
Cellulosic Plastics
Eastman Chemical Company was established as an independent supplier of chemicals for their photographic processes. They established two major platforms - organic chemicals and acetyls. Leveraging their knowledge of acetyl chemistry, Eastman began making compounded cellulose acetate, literally "Plastics From Trees," in 1929 soon thereafter, this was sold under the Tenite™ cellulosics trade name (uspto.gov ). Tenite™ cellulosics comprise a family of products grouped in three major categories, as shown below. Early applications of Tenite™ included several iconic consumer products, such as the first football helmets, early TVs, radios, and telephones, Duncan yo-yo's, and others. The process to make Tenite™ starts with softwood trees, which are pulped. This pulp is used to make a cellulose ester which is then mixed with plasticizers and other additives to produce plastic pellets, which are converted into plastic products.These include Tenite™ Acetates, Tenite™ Butyrates, Tenite™ Propionates