Sustainable Production of Fuels and Missile Propellants
Abstract
APPROVED FOR PUBLIC RELEASE.This Program NEPTUNE research project involves the deployment of catalytic and electrochemical technologies to efficiently and economically convert renewable platform molecules into biobased, net-zero carbon fuels, with a major focus on densely branched hydrocarbons that can serve as biobased gasoline/aviation fuel blendstocks and high-energy tactical fuels. The objectives of the project are organized under the following Tasks:(Task 1) Technology development and engineering of the electrochemical production of C9-C15 isoalkane/cycloakane jet fuels: This activity describes the deployment of a simple, highly efficient electrochemical cell for the oligomerization of biogenic acetone. Acetone is efficiently derived from biomass via the acetone-butanol-ethanol fermentation or alternatively the ketonization of acetic acid. In preliminary work, we have obtained a mixture of highly branchedalkanes and cycloalkanes that are related to the products in Tasks 2 and 3 but higher in molecular weight and therefore ideal for use in aviation fuel, a renewable market that is largely underdeveloped compared to diesel-type fuels. In our first NEPTUNE project we generated electrolysis products which, after hydrodeoxygenation, showed conversion to a multicomponent hydrocarbon mixture that was comparable in specifications to commercial Jet-A. In the continuation of this project, we will further optimize the reaction parameters and scale production up to several liters for advanced fuel testing in the Problem Sponsor s Navy laboratory and by Chevron. (Task 2) Engineering the levulinic acid to C8-C9 branched alkane/cycloalkane route to gasoline-type fuels: In earlier work, we demonstrated the technical feasibility of converting levulinic acid, a platform molecule generated in high yield directly from raw biomass, into branched hydrocarbons suitable for use in gasoline. The commercial advantage of this technology is that isoalkanes, which constitute the largest consumer fuel market, are normally difficult to produce from cellulose, which has a linear carbon chain. The method involves highly efficient steps starting from plant biomass all the way to liquid hydrocarbons, with minimal hydrogen usage. Nowthat the technology has been proven at the bench, it is ready to be progressed to the next level, i.e. optimization and scale-up for advanced fuel testing and translation finally to commercial-scale production. The plan for this project is to engineer a continuous process at the liter scale to model its ultimate piloting to hundreds of liters.(Task 3) Technology development of the levulinic acid route to cyclopentadienes and therefrom to high-energy polycyclic hydrocarbons: We have recently concluded a model study of the base-catalyzed dimerization of esters of levulinic acid (cf. Task 2) to give cyclopentadienes. Hydrodecarboxylation/hydrodeoxygenation of these products leads to densely branched, super high-octane cyclopentanes. In collaboration with the Problem Sponsor, we propose here to investigate the cycloaddition of these cyclopentadienes with olefins, which will give substituted bicycloalkanes. Such compounds are related to the tactical synthetic fuel JP-10, used for example by the Tomahawk jet-powered cruise missile. A range of novel, high-energy, biobased propellants will be produced using this approach.DoD Impact: In Tasks (1)-(3) above, arguments can be made for a win for the Navy in terms not only of technological capability advancement and environmental stewardship, but also for the economics of fuel procurement, which will be competitive with that of fuels from petroleum.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 06, 2023
- Source ID
- N000142312219
Entities
People
- Mark Mascal
Organizations
- Office of Naval Research
- United States Navy
- University of California, Davis