Chemical Engineering

1975 B.S. in Chemical Engineering, Andhra University, India 
1977 M.S.Ch.E., Indian Institute of Technology, Kanpur 
1983 Ph.D. in Chemical Engineering, State University of New York at Buffalo

Our current research activities are mainly in three areas: (1) using ionic liquids (ILs) as “green solvents”; (2) biocatalysis; and (3) colloids and surface phenomena. In the first area, we are interested in the use of ILs (i) for pretreatment of biomass to achieve enhanced enzymatic saccharification for fuel and chemical production, and (ii) as extracting solvents for bioproducts. In the area of biocatalysis, we are using immobilized enzyme catalysis and fermentations involving native and genetically engineered microorganisms (GMOs). In the third area, we are applying the principles of colloidal and surface phenomena in separation processes. Our applications include protein crystal nucleation kinetics and membrane separation processes (facilitated transport & active transport).

1. Alipour S., Relue, P., Viamajala, S., and Varanasi, S., High Yield 5-Hydroxymethylfurfural Production from Biomass Sugar at Facile Reaction Conditions: Implementation of Simultaneous-Isomerization-and-Reactive Extraction, Back-Extraction, and Dehydration, Energy and Environmental Science (under review).
2. Maddi B, Viamajala S, Varanasi S. 2013. “Pyrolytic fractionation: A promising thermo-chemical technique for processing oleaginous (algal) biomass” Energy and Environmental Science (under review).
3. Mudiyanselage A. Y., Viamajala S., Varanasi, S., and Yamamoto K., “A simple ring-closing metathesis approach for synthesis of nylon 11–13 precursors from oleic acid”, ChemSusChem (under review)
4. Bin Li, S. Varanasi and P. Relue, “High yield aldose–ketose transformation for isolation and facile conversion of biomass sugar to furan”, Green Chemistry, 15, (2013), 2149-2157.
5. Bin Li, P. Relue, and S. Varanasi, Simultaneous isomerization and reactive extraction of biomass sugars for high yield production of ketose sugars, Green Chemistry, 14 (2012) 2436-2444.
6. Y. Dawei, K. Rao, P. Relue and S. Varanasi, A viable method and configuration for fermenting biomass sugars to ethanol using native Saccharomyces cerevisiae, Bioresource Technology, 117(2012) 92-98
7. B. Maddi, S. Viamajala, and S. Varanasi “Comparative study of pyrolysis of algal biomass from natural lake blooms with lignocellulosic biomass” Bioresource Technology, 102 (2011) 11018–11026
8. Kripa Rao, Y. Dawei, P. Relue and S. Varanasi “Fermentation of biomass sugars to ethanol using native industrial yeast strains” Bioresource Technology, 102 (2011) 3246–3253
9. P.Li, Q. Zhao, J. L. Anderson, S. Varanasi and M. Coleman, Synthesis of coplyimides based on room temperature ionic liquids, Journal of Polymer Science: Part A: Polymer Chemistry, vol 48, 4036-4046, (2010)
10. R. A. Gosavi, V. Bhamidi, S. Varanasi, and C. A. Schall, “Beneficial Effect of Solubility Enhancers on Protein Crystal Nucleation and Growth, Langmuir, vol. 25, pp.4579 – 4587 (2009)
11. F. Zhao, T.K. Ponnaiyan, C. M. Graham, C.A. Schall, S. Varanasi, and J. Anderson “Determination of ethanol in ionic liquids using headspace solidphase microextraction–gas chromatography, Analytical and Bio analytical Chemistry, 392 pp 1271-1275, 2008.
12. K. Rao, S. Chelikani, P. Relue, and S. Varanasi, “A Novel technique for Optimizing the Simultaneous-Isomerization-and-Fermentation (SIF) Approach of Converting Xylose to Ethanol, Applied Biochemistry and Biotechnology, 146, pp. 101-117 (2008)
13. Anantharam P. Dadi, C. A. Schall and S. Varanasi “Mitigation of Cellulose Recalcitrance to Enzymatic Hydrolysis by Ionic Liquid Pretreatment” Applied Biochemistry and Biotechnology, 136-140, pp. 407-421(2007)
14. K.Rao,V. Chaudari, D.-S. Kim, and S. Varanasi, “Enhanced Ethanol Fermentation of Brewery Waste Water Using the Genetically Modified Strain, E. coli KO11, Applied Microbiology and Biotechnology, 74, pp.50-60 (2007).
15. Anantharam P. Dadi, S. Varanasi and C. A. Schall “Enhancement of cellulose saccharification Kinetics using an ionic liquid pretreatment step”, Biotechnology and Bioengineering, vol. 95, pp 904-910 (2006)

1. S. Varanasi, C. Schall, A. P. Dadi, J. Anderson, K.Rao, P. Paripati, and G. Kumar, “Biomass Pretreatment”, US patent # 8,546,109; issued: October 1, 2013 (Divisional Patent)
2. S. Varanasi, K. Rao, P.Relue, and D. Yuan “Methods for fermentation of xylose and hexose sugars,” US Patent # 8,507,232, issued August 13, 2013
3. S. Varanasi, C. Schall and A.P. Dadi “Production of ethanol from saccharified cellulose following Ionic Liquid pretreatment”, US patent # 8,236,536, issued: August 7, 2012
4. S. Varanasi, C. Schall, A. P. Dadi, J. Anderson, K.Rao, P. Paripati, and G. Kumar, “Biomass pretreatment”, US patent # 8,030,030, issued: October 4, 2011
5. S. Varanasi, C. Schall and A. P. Dadi “Saccharifying Cellulose”, US patent # 7,674,608, Issued: March 9, 2010
6. J. Byers, R. Fournier, S. Varanasi, “Method of Producing Products with a bilayer pellet containing a coimmobilized enzyme system that maintains a pH difference”, US Patent # 5,397,700
7. J. Byers, R. Fournier, S. Varanasi, “Bilayer pellet containing immobilized xylose isomerase and urease for the simultaneous isomerization and fermentation of xylose to ethanol”, US Patent # 5,254,468
8. S. Varanasi, K. Rao, P.Relue, and D. Yuan “Methods for fermentation of xylose and hexose sugars,” U.S. Patent Application 20130330800; US Divisional Patent filed August 12, 2013
9. B. Li, S. Varanasi and P. Relue. “Aldose-ketose transformation for separation and/or chemical conversion of C6 and C5 sugars from biomass materials”. U.S. Patent Application 20130074397, PCT/US11/33030, November 7, 2012.
10. G. Lipscomb, S. Varanasi, P. Paripati, A. P. Dadi, “Ionic liquid Recovery and Purification in Biomass Pretreatment Processes” U.S. Patent Application 20130292331, November 7, 2013
11. G. Lipscomb, S. Varanasi, P. Paripati, A. P. Dadi, “Liquid Recovery and Purification in Biomass Pretreatment Processes” U.S. Patent Application 20120298584, November 29, 2012
12. S. Alipour, B. Li, S. Varanasi, P. Relue, and S. Viamajala, “New methods for high yield production of furans from biomass sugars at mild operating conditions,” US Provisional Patent filed 11/1/2013
13. Maddi B.; Viamajala, S.; Varanasi, S. 2011. Thermal Fractionation of biomass of non-lignocellulosic origin for multiple high-quality biofuels (US Patent Pending) #13/294510.
14. H. Shao, A. Vadlamani, S. Viamajala, S. Varanasi and P. Relue. “Enzymatic digestion of microalgal biomass for lipid, sugar, and protein recovery,” Provisional US Patent application, D2013-77, filed April 29, 2013.
15. Yamamoto K., Viamajala S., Varanasi S., Nguyen K., Abel G., Mudiyanselage A. Y., Cross Metathesis Approach to C12 and C13 Fatty-Chain Amino Esters from Oleic Acid Derivatives, (US Patent Pending) #1-56166/D2014-06
16. Yamamoto K., Viamajala S., Varanasi S., Nguyen K., Mudiyanselage A. Y Ring Closing Metathesis Approach To Produce Precursors Of Nylon 11, 12, And 13 From Oleic Acid (US Patent Pending)

Received funded from National Science Foundation, US DOE, USDA, US Air Force Office, Ohio Third Frontier Commission; Ohio Coal Development Office, DOE-SBIR, and USDA-SBIR; some recent grants are listed below.

The Ionic Liquid Pretreatment technology developed for lignocellulosic biomass processing is licensed to industry and is being commercialized.

1. “Integration of Nutrient and Water Recycling for Sustainable Algal Biorefineries.” PI: Viamajala S,Co-Is: Varanasi S, Gerlach R, Characklis W, Hamud I, Johnson R, Fields M, Peyton B. Funded by the US Department of Energy, Office of the Biomass Program. Collaborating Institutions – The University of Toledo, Montana State University, University of North Carolina, City of Logan (Environmental Department) and Advanced Algae Solutions, LLC. Lead Institution – The University of Toledo. Total project award: $2,999,934. UT award: $1,140,508. Role: Project Co-PI. September 2012. (Duration – 3 yrs)
2. “SEP Collaborative: Alkaliphilic microalgae-based sustainable & scalable processes for renewable fuels and products.” PI: Viamajala S,Co-Is: Gerlach R, Characklis W, Varanasi S, Yamamoto K, Fields M, Peyton B. Agency: National Science Foundation’s (NSF) Sustainable Energy Pathways (SEP) Program. Collaborating Institutions – The University of Toledo, Montana State University and University of North Carolina. Lead Institution – University of Toledo. Total project award: $1,900,000. UT award: $950,000. August 2012. (Duration – 4 yrs)
3. “Center for Algal Engineering Research and Commercialization.” Bayless D, Viamajala S, Stuart B, Varanasi S et al. Agency: Ohio Third Frontier’s Wright Project program. Collaborating Institutions – Ohio University and The University of Toledo. Lead Institution: Ohio University. Total project award: $2,970,063. UT award: $1,027,061; Role: Co-PI for UT award. May 2010. (Duration – 3 yrs)
4. “MRI-R2: Acquisition of a suite of analytical instrumentation essential for investigating fuel, chemical and polymer production from biomass.” PI: Varanasi S, Co-Is: Lapitsky Y, Viamajala S, Anderson J, Schall C., Funded by the NSF Division of Chemical, Bioengineering, Environmental, and Transport Systems (CBET) Major Research Instrumentation (MRI) program. Award: $992,690. April 2010 (Duration – 3 yrs)
5. Simultaneous Isomerization and Reactive Extraction of Biomass Sugars for Efficient Furan Production via High Yield Ketose Intermediate (PI: Sasidhar Varanasi Co-I: P. Relue) Award Period: August, 2012 – August 2015 Award: $309,523 Agency: National Science Foundation.
6. “Pilot Scale demonstration of cellulosic-ethanol process” SuGanit Systems, Inc and University of Toledo (UT subcontract $250,000; PI: S. Varanasi), 2011 Third Frontier Advanced Energy Program - State of Ohio, Total award $1,000,000, April 2011 – March 2013.
7. “Pilot Scale demonstration of cellulosic-ethanol process” (PI: S. Varanasi), 2011-Wright Projects Program – Ohio Department of Development, Total award $1,000,000, April 2011 – March 2014.
8. “Direct Catalytic Conversion of Lignin to Aromatic Chemicals” (PI: Mark Mason, Co-I: Sasidhar Varanasi) subcontract from SuGanit Systems Inc.on Department of Energy- SBIR Phase 1; award period: 4/18/2012- 11/19/2012 Award : $150,000; Subcontarct $50,000.
9. Alkaliphilic microalgae-based processes for renewable fuels and chemicals, (PI: Sridhar Viamajala, Co-Is: Sasidhar Varanasi, Kana Yamomoto; Dragan Isailovic) Interdisciplinary Research Initiation Awards Program, Office of Research and Sponsored Programs, The University of Toledo, $100,000 Duration: May 2012-April 2013
10. A facile pretreatment strategy for recovering sugars and lignin effectively from a variety of lignocellulosic feedstocks (PI:S. Varanasi Co-I: C. Schall) Award Period: September, 2009 – August 2012 Award: $310,945 Agency: National Science Foundation
11. Development of co-immobilized enzyme pellet to replace GMO’s for cellulosic ethanol production (UT faculty: PI: S. Varanasi, Co-I: P.Relue) Award Period: June 2009 – June 2011 Award: Total award $80,000 UT subcontract from SuGanti Systems: $36,000, Agency: US Department of Agriculture, SBIR-Phase 1
12. Renewable Hydrocarbon Fuels from Algae, (PI: Sasidhar Varanasi); Award Duration: 6/05/2009 – 12/13/2011, Amount: $138, 461, Agency: US Air Force Office of Research via a subcontract through Center for Innovative Food Technology.
13. Scale-up of Ionic Liquid Recovery Methods following Biomass Pretreatment ,Award Period: September. 2009 – August 2011 Amount: $228,516 Agency: Suganit systems, inc. (subcontract on Department of Energy SBIR Phase II; Total award $750,000)
14. Lab-scale set-up to convert biomass into valuable products through integral pyrolysis and steam reformation units, Award Period: January 2010 – June 2010 Amount $50,000 Agency: REII (subcontract on a Department of Energy pilot scale Demonstration grant) (PI: S. Varanasi, Co-I: G.G. Lipscomb)
15. A novel simultaneous-saccharification-fermentation strategy for efficient co-fermentation of C5 and C6 sugars using native, non-GMO yeasts, PI: S Varanasi, Co-I: P. Relue, Department of Energy- Office of Biomass Program, $500,000, February 2009 – January 2012.
16. “Scale up of Cellulosic Ethanol Process Based on Novel Biomass Pretreatment and Efficient Co-Fermentation,” SuGanit Systems, Inc and University of Toledo (UT subcontract $505,000; PI: Sasidhar Varanasi, Co-Is: C. Schall, P. Relue, and J. Anderson), 2009 Third Frontier Advanced Energy Program - State of Ohio, $999,900, April 2009 – March 2012.
17. “A Novel Cellulosic Biomass Fermentation Process for Ethanol Production,” PI: S. Varanasi, Co-Is P. Relue, P. Paripati, and G. Kumar, 2008 Third Frontier Advanced Energy Program – State of Ohio, $250,000, June 2008 – August 2009.
18. Total Award: $100,000 (Sub-contract $33,000); Award Period: 06/2008- 12/2008; Project Title: Feasibility of commercialization of a pretreatment process for enhanced biomass saccharification (Sub-contractor to SuGanit Systems.with C. Schall); Sponsor: Department of Energy - SBIR (Phase 1)