Niu: Separation of Ethanol-Water Mixtures Using Canola Meals

Date: June 2011
Term: 3 years
Status: Completed
Researcher(s): Dr. Catherine Niu and Dr. Ajay Dalai, Department of Chemical and Biological Engineering, University of Saskatchewan
SaskCanola Investment: n/a
Total Project Cost: n/a
Funding Partners: Pound-maker Investments Ltd.

Project Summary

Researchers at the University of Saskatchewan conducted a three-year study to determine if cost-effective biosorbents from canola meal would have potential for industrial application of dehydration of ethanol, other alcohols or gases. The research results demonstrated that canola meal either in its raw form or after protein extraction has great potential for ethanol drying in industry. The results also showed that canola meals after being used for ethanol dehydration still retain their major nutrients, which have great potential for animal feed.

Researchers at the University of Saskatchewan conducted a three-year study to determine if cost-effective biosorbents from canola meal would have potential for industrial application of dehydration of ethanol, other alcohols or gases. The goal was to develop cost-effective biosorbents from canola meal to selectively remove water from the ethanol-water mixtures to obtain fuel grade ethanol. The project objectives were to develop and characterize biosorbents made from canola meal, optimize the conditions for selective water uptake in ethanol-water mixtures using the biosorbents, and establish an adsorption column system capable of drying ethanol with high (90%) to low (4%) water content to obtain fuel grade and anhydrous ethanol.

Through the project, canola meal biosorbents were successfully made in the forms of particles, and cylindrical pellets. The biosorbent pellets enhanced the stability of canola meal material. Two lab-scale adsorption column systems were established in the laboratory of the University of Saskatchewan to optimize the performance of the canola meal biosorbents for ethanol dehydration. They include a fixed-bed water adsorption and a Pressure Swing Adsorption (PSA) process, which mimics the PSA process in bioethanol plants. Researchers also found that the nutrients originally contained in the canola meal including minerals and proteins did not change significantly in the canola meal pellets after being used in ethanol dehydration for over a year.

Research results also showed canola meal after protein extraction not only has effective and increased water uptake, but also has higher water selectivity over ethanol. The results showed that alkali method is effective for extracting protein from canola meal. The canola meal residues after such treatment are still effective for selective water uptake. It may be because the alkali treatment helps dissociate dense structures of cellulose or hemi-cellulose of canola meal so that more functional sites are available for water uptake.

Figure 2. Canola meal bisorbents – canola meal pellets, 5 mm in diameter and 3mm in thickness.

The research results demonstrated that canola meal either in its raw form or after protein extraction has great potential for ethanol drying in industry. The results also showed that canola meal after being used for ethanol dehydration still retain their major nutrients, which have great potential for animal feed.

Overall, the results achieved through this project indicate canola meal has a great potential for industrial application of dehydration of ethanol, other alcohols or gases. Based on the results achieved from the project, researchers filed a US provisional in October 2010.

Note: Scroll to Page 3 to view Figure 3 and Figure 4.

Figure 3. Fixed bed water absorption system.

Condenser

AdsorptionColumn

Water circulator to maintain the temperature of the column

Fraction Collector

Evaporator
Figure 4. Pressure Swing Adsorption system.

Full Report PDF: Separation of Ethanol-Water Mixtures Using Canola Meals