OUR SUGAR-TO-GLYCOL PROCESS
Using renewable sugars in place of conventional fossil fuel feedstocks (ethylene, propylene, naptha) S2GBiochem’s glycol production process is both sustainable and profitable. A plant based on our technology produces over 200,000 tonnes annually. Costs are competitive with petrochemical glycols with substantially fewer GHG emissions.
S2G’s bio-glycol plants are based on the conversion of sugars to mixed glycols, (“Sugar-to-Glycol”). The sugars may be 6-carbon (C6) glucose or fructose, 5-carbon (C5) xylose or arabinose or 3-carbon (C3) glycerine. The 2-stage Sugar-to-Glycol process involves a catalytic hydrogenation of glucose, sucrose, xylose and/or arabinose to intermediate alditols: e.g. C5 xylose to xylitol; C6 glucose/sucrose to sorbitol. A second hydrogenolysis stage then converts the alditols to mixed glycols (ethylene glycol, propylene glycol, butandiol) and alcohol (methanol, ethanol)
Figure 1: Sugars-to-Glycols Process.
The hydrogenolysis of sorbitols/xylitol also produces glycerine –typically about 15%. Glycerine (glycerol) is an alditol and can be recycled to the hydrogenolysis stage and reacted to produce additional glycol. Additional glycerine can also be added between the stages as an alternate source of feedstock.
The process is a continuous, liquid-phase reaction at elevated pressure and temperature. The proprietary, non-precious metal catalysts are widely available and economical. The overall conversion efficiency is 85-95%.
The typical product slate from the Sugar-to-Glycol process is shown below:Table 1: Product Slate
|Products||% of Products Produced,
Other processing steps in a commercial plant include sugar feedstock pre-treatment, glycol separations and hydrogen recovery/recycle.
Figure 2: Block Flow Diagram for Plant (click to enlarge)
Our partner, International Polyol Chemical, Inc. (ICPI) is a world leader in the development of Sugar-to-Glycol hydro-cracking technology and related glycol separations. Along with its partners, IPCI has assembled a suite of over 30 technology patents.
Developed over 15 years and with an investment of $20 million, the Sugar-to-Glycol technology based on C6 corn glucose, led to a commissioned 10,000 MT/yr pilot plant in Northeast China in 2005. Based on the success of this pilot plant, a 200,000 MT/yr plant went on line in 2007 becoming the first green glycols plant worldwide.