Robert Malina

Production of renewable jet fuel range alkanes and commodity chemicals from integrated catalytic processing of biomass

This article presents results from experimental studies and techno-economic analysis of a catalytic process for the conversion of whole biomass into drop-in aviation fuels with maximal carbon yields. The combined research areas highlighted include biomass pretreatment, carbohydrate hydrolysis and dehydration, and catalytic upgrading of platform chemicals. The technology centers on first producing furfural and levulinic acid from five- and six-carbon sugars present in hardwoods and subsequently upgrading these two platforms into a mixture of branched, linear, and cyclic alkanes of molecular weight ranges appropriate for use in the aviation sector. Maximum selectivities observed in laboratory studies suggest that, with efficient interstage separations and product recovery, hemicellulose sugars can be incorporated into aviation fuels at roughly 80% carbon yield, while carbon yields to aviation fuels from cellulose-based sugars are on the order of 50%. The use of lignocellulose-derived feedstocks rather than commercially sourced model compounds in process integration provided important insights into the effects of impurity carryover and additionally highlights the need for stable catalytic materials for aqueous phase processing, efficient interstage separations, and intensified processing strategies. In its current state, the proposed technology is expected to deliver jet fuel-range liquid hydrocarbons for a minimum selling price of

Lifecycle greenhouse gas footprint and minimum selling price of renewable diesel and jet fuel from fermentation and advanced fermentation production technologies

4.75 per gallon assuming nth commercial plant that produces 38 million gallons liquid fuels per year with a net present value of the 20 year biorefinery set to zero. Future improvements in this technology, including replacing precious metal catalysts by base metal catalysts and improving the recyclability of water streams, can reduce this cost to

Quantifying the climate impacts of albedo changes due to biofuel production: a comparison with biogeochemical effects.

2.88 per gallon.

Global, regional and local health impacts of civil aviation emissions

Fermentation and advanced fermentation (AF) biofuel production technologies may offer a means to reduce the greenhouse gas (GHG) intensity of transportation by providing renewable drop-in alternatives to conventional middle distillate (MD) fuels, including diesel and jet fuel. To the best of our knowledge, this is the first peer-reviewed study of the environmental and economic feasibility of AF technologies. We find that the attributional lifecycle GHG footprint of AF MD from sugar cane, corn grain and switchgrass ranges from −27.0 to 19.7, 47.5 to 117.5, and 11.7 to 89.8 gCO2e/MJMD, respectively, compared to 90.0 gCO2e/MJMD for conventional MD. These results are most sensitive to the co-product allocation method used, the efficiency and utility requirements of feedstock-to-fuel conversion, and the co-generation technology employed. We also calculate the minimum selling price (MSP) of MD fuel produced from sugar cane, corn grain and switchgrass AF as a range from 0.61 to 2.63, 0.84 to 3.65, and 1.09 to 6.30

The costs of production of alternative jet fuel: A harmonized stochastic assessment

per literMD, respectively, compared to the current price of conventional MD in the United States of approximately 0.80

Environmental and economic tradeoffs of using corn stover for liquid fuels and power production

per literMD. The MSP results are most sensitive to feedstock-to-fuel conversion efficiency, feedstock costs, and capital costs. Finally, we demonstrate that emissions from land use change (LUC) directly attributable to the growth of biomass for AF fuel could dominate the GHG footprint of AF MD fuels.

Stochastic techno-economic analysis of alcohol-to-jet fuel production

Lifecycle analysis is a tool widely used to evaluate the climate impact of greenhouse gas emissions attributable to the production and use of biofuels. In this paper we employ an augmented lifecycle framework that includes climate impacts from changes in surface albedo due to land use change. We consider eleven land-use change scenarios for the cultivation of biomass for middle distillate fuel production, and compare our results to previous estimates of lifecycle greenhouse gas emissions for the same set of land-use change scenarios in terms of CO2e per unit of fuel energy. We find that two of the land-use change scenarios considered demonstrate a warming effect due to changes in surface albedo, compared to conventional fuel, the largest of which is for replacement of desert land with salicornia cultivation. This corresponds to 222 gCO2e=MJ, equivalent to 3890% and 247% of the lifecycle GHG emissions of fuels derived from salicornia and crude oil, respectively. Nine of the land-use change scenarios considered demonstrate a cooling effect, the largest of which is for the replacement of tropical rainforests with soybean cultivation. This corresponds to 161 gCO2e=MJ, or 28% and 178% of the lifecycle greenhouse gas emissions of fuels derived from soybean and crude oil, respectively. These results indicate that changes in surface albedo have the potential to dominate the climate impact of biofuels, and we conclude that accounting for changes in surface albedo is necessary for a complete assessment of the aggregate climate impacts of biofuel production and use.

Using Dynamic Relative Climate Impact curves to quantify the climate impact of bioenergy production systems over time

Aviation emissions impact surface air quality at multiple scales?from near-airport pollution peaks associated with airport landing and take off (LTO) emissions, to intercontinental pollution attributable to aircraft cruise emissions. Previous studies have quantified aviation?s air quality impacts around a specific airport, in a specific region, or at the global scale. However, no study has assessed the air quality and human health impacts of aviation, capturing effects on all aforementioned scales. This study uses a multi-scale modeling approach to quantify and monetize the air quality impact of civil aviation emissions, approximating effects of aircraft plume dynamics-related local dispersion (?1 km), near-airport dispersion (?10 km), regional (?1000 km) and global (?10 000 km) scale chemistry and transport. We use concentration-response functions to estimate premature deaths due to population exposure to aviation-attributable PM2.5 and ozone, finding that aviation emissions cause ?16 000 (90% CI: 8300?24 000) premature deaths per year. Of these, LTO emissions contribute a quarter. Our estimate shows that premature deaths due to long-term exposure to aviation-attributable PM2.5 and O3 lead to costs of ?

Life Cycle Greenhouse Gas Emissions and Costs of Production of Diesel and Jet Fuel from Municipal Solid Waste

21 bn per year. We compare these costs to other societal costs of aviation and find that they are on the same order of magnitude as global aviation-attributable climate costs, and one order of magnitude larger than aviation-attributable accident and noise costs.

Techno-economic and environmental evaluation of producing chemicals and drop-in aviation biofuels via aqueous phase processing

This study quantifies and compares the costs of production for six alternative jet fuel pathways using consistent financial and technical assumptions. Uncertainty was propagated through the analysis using Monte Carlo simulations. The six processes assessed were HEFA, advanced fermentation, Fischer-Tropsch, aqueous phase processing, hydrothermal liquefaction, and fast pyrolysis. The results indicate that none of the six processes would be profitable in the absence of government incentives, with HEFA using yellow grease, HEFA using tallow, and FT revealing the lowest mean jet fuel prices at