The broader impact/commercial potential of this project will lead to the development of a new technology for a higher alcohols production process that will provide a cost competitive method for producing C6-C13 alcohols (with 6 to 13 carbons) from a renewable feedstock. C6-C13 linear and branched alcohols are used in a variety of applications such as solvents, cosmetics, plasticizers, and surfactants, with a current global demand in excess of 5 million tons per year. It is expected that the process for producing these alcohols will provide at least 30% reduction in capital cost, energy consumption, waste produced and thereby has potential to replace the process by which higher alcohols are currently produced. A major benefit of this new process is substitution of petroleum based non-renewable feedstock with inexpensive, abundant, domestically sourced ethanol. This process will also allow ethanol producers to convert ethanol ($0.4/pound) to a higher value product, plasticizer alcohols, which are priced at $0.95 - $1.2/lb. Utilizing ethanol as a feedstock to make high value chemicals can enable the US ethanol industry to find other markets for ethanol that will supplement the current gasoline additive market and help new cellulosic ethanol technologies gain market access even as the blend wall is reached.
This Small Business Innovation Research Phase I project will enable the development of a one- step catalytic process for making higher alcohols that are currently produced via complicated, multi-step processes employing precious metal-based catalysts and petroleum derived feedstock. The focus of Phase I work will be on developing and characterizing novel catalysts, optimizing reaction conditions and understanding the reaction mechanism and kinetics. The proposed one-step process requires a dual-function catalyst that must both act as an alcohol/aldehyde dehydrogenation/hydrogenation catalyst and an aldol condensation catalyst, and identifying a suitable catalyst will be the major hurdle for project success. If successful, catalyst(s) will be developed that can convert bio/renewable ethanol (more than 20%) into plasticizer alcohols with 6 to 13 carbons (greater than 45% selectivity) in a single-pass fixed-bed reactor with no change in performance for at least 500 hours of operation. The current best catalysts can achieve the required ethanol conversion, but selectivity to heavier alcohols remains well below target. Development of catalysts that can meet the selectivity requirement would represent a major advancement in the development of this technology.
Greenyug, LLC is developing a new, cost competitive technology for the production of higher alcohols (linear and branched alcohols with six to 13 carbons) from a renewable ethanol feedstock. Higher alcohols are used in a variety of applications such as solvents, cosmetics, plasticizers, and surfactants, with a current global demand in excess of 5 million tons per year. Compared to the current state-of-the-art process, the Greenyug process is projected to reduce the carbon footprint of higher alcohol production by at least 50%, halve the capital investment, reduce the energy usage by more than 30%, and, at the same time, provide a 20% lower cost of production. A major benefit of this new process is substitution of the current petroleum-based non-renewable feedstock with inexpensive, abundant, domestically sourced ethanol. This process will also allow ethanol producers to convert ethanol ($0.4/pound) to a higher value product, higher alcohols, which are priced at $0.95 - $1.2/lb. Utilizing ethanol as a feedstock to make high value chemicals can enable the US ethanol industry to find other markets for renewable ethanol that will supplement the current gasoline additive market, and help new cellulosic ethanol technologies gain market access even as the gasoline "blend wall" is reached. In order to make the Greenyug process for producing higher alcohols possible, a catalyst capable of transforming ethanol into longer chain alcohols must be developed. This catalyst needs to meet minimum performance benchmarks in three different areas - conversion, selectivity, and stable long duration performance - to be economically viable. Greenyug’s Phase I effort focused on developing a catalyst that would meet the performance benchmarks by synthesizing a number of classes of catalysts with varying compositions and testing their performance. One class of catalysts met both the selectivity and stability benchmark, and only needs slight improvement to meet the conversion benchmark. Modifications to this catalyst class to improve its performance will be a major focus of Greenyug’s research and development effort going forward. In addition to identifying a potential viable catalyst, the feasibility of the Greenyug process for making higher alcohols was confirmed during the Phase I work. The results of laboratory experiments using pure ethanol as well as mixed feeds of ethanol and higher alcohols were used to create engineering simulations that supported initial assumptions made about the Greenyug process. The experimental work and simulations performed during Phase I proved the technically feasibility of the Greenyug process for converting renewable ethanol into higher alcohols.
