Duckweed biomass is gasified in a thermochemical-based superstructure to produce gasoline, diesel, and kerosene using a synthesis gas intermediate. The superstructure includes multiple pathways for conversion of the synthesis gas to liquid hydrocarbons via Fischer−Tropsch synthesis or intermediate methanol synthesis. Low-temperature and high-temperature Fischer−Tropsch processes are examined us...

Middle distillate (MD) transportation fuels, including diesel and jet fuel, make up almost 30% of liquid fuel consumption in the United States. Alternative drop-in MD and biodiesel could potentially reduce dependence on crude oil and the greenhouse gas intensity of transportation. However, the water and land resource requirements of these novel fuel production technologies must be better unders...

Converting remote natural gas to liquid fuel is one possible solution to the problem of transporting remote gas to the energy market. However, the high investment cost of gas-to-liquid (GTL) plants prevents large scale exploitation of remote gas reserves. A lean GTL is suggested based on an autothermal reformer with enriched air as oxidant and a once-through Fischer-Tropsch synthesis. In order ...

the kinetic of fischer-tropsch synthesis over a co-precipitated fe-ce catalyst was investigated in a fixed bed micro reactor. experimental conditions were varied as follow: reaction pressure 1-15bar, h¬¬¬2/co feed ratio of 1-3 and space velocity of 3600-5400 h-1 at the temperature range of 270-310°c. 4 models according to the langmuir-hinshelwood-hougen-watson (lhhw) type rate equation were der...

In this concise review paper, we will address recent studies based on the generalized-gradient approximation (GGA) of the density functional theory (DFT) and on the periodic slab approach devoted to the understanding of the Fischer-Tropsch synthesis process on transition metal catalysts. As it will be seen, this computational combination arises as a very adequate strategy for the study of the r...

This paper proposes a multiobjective, mixed-integer nonlinear programming (MINLP) model for the superstructure optimization of hydrocarbon biorefineries via gasification pathway under economic and environmental criteria. The proposed hydrocarbon biorefinery superstructure includes a number of major processing stages, such as drying of the cellulosic biomass feedstocks, air separation unit, gasi...

Mesoporous H-ZSM-5–carbon composites, prepared via tetrapropylammonium hydroxide (TPAOH) post treatment of H-ZSM-5 followed by deposition of pyrolytic carbon, have been used as the support for the preparation of Co-based Fischer–Tropsch catalysts. The resulting catalysts display an improved performance during Fischer–Tropsch synthesis (FTS), with higher activity, higher selectivity towards C5–C...

We present in situ experiments to study the possible formation of cobalt carbides during Fischer–Tropsch synthesis (FTS) a Co/TiO2 catalyst at relevant conditions pressure and temperature. Th...

INTRODUCTION The altitude threshold for decompression sickness (DCS) symptoms has been variously described as being 18,000 ft (5,487 m) to above 25,000 ft (7,620 m). Safety and efficiency of aerospace operations require more precise determination of the DCS threshold. METHODS Subjects were 124 males who were exposed to simulated altitudes (11 at 11,500 ft; 10 at 15,000 ft; 8 at 16,500 ft; 10 ...

Fischer−Tropsch synthesis (FTS, CO + H 2 → long-chain hydrocarbons) for its great significance in the industry has attracted huge attention since discovery. For Fe-based catalysts, after decades of...