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At least 829 records · Page 46
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Catalytic hot-gas filtration of biomass pyrolysis vapors

The present disclosure relates to a device that includes a filter element and a catalyst, where the filter element is configured to remove particulate from a stream that includes at least one of a gas and/or a vapor to form a filtered stream of the gas and/or the vapor, the catalyst is configured to receive the filtered stream and react a compound in the filtered stream to form an upgraded stream of the gas and/or the vapor, further including an upgraded compound, and both the filter element and the catalyst are configured to be substantially stable at temperatures up to about 500° C.

Magrini, Kimberly A.↗
DOE OSTI2023

Materials and methods for improved pyrolysis processing

The present disclosure relates to a catalyst that includes a support that includes a metal oxide and a metal deposited on the support, where the metal oxide includes at least one of TiO 2 , Al 2 O 3 , SiO 2 , CeO 2 , and/or ZrO 2 , the metal includes at least one of Pt, Pd, Ru Rh, Ni, and/or Mo, the metal is in the form of a particle, and the metal is present on the support at a concentration between about 0.1 wt % and about 5.0 wt %.

Griffin, Michael Brandon↗
DOE OSTI2024

Systems Analysis Perspectives of Methane Pyrolysis, Fossil-Based Ammonia Production, and H2 and NG/H2 Transport (FWP-1022467 (5, 7, 8))

This poster presentation provides an overview of NETL’s work focused towards supporting the development of technical solutions to: 1) produce economical and low-carbon hydrogen from natural gas; 2) advance hydrogen sensing technologies for the existing natural gas pipelines; 3) evaluating new infrastructure to be used to transport hydrogen safely at a large scale; and 4) produce sustainable chemicals and fuels, such as ammonia, from natural gas resources, including methane emissions from flare gas.

Sheriff, Alana↗
DOE OSTI2024

Co-Processing Fast Pyrolysis Bio-Oils and Hydrothermal Liquefaction Biocrudes in Fluid Catalytic Cracking and Hydroprocessing in Refineries

Co-processing of biogenic feedstocks within the existing petroleum infrastructure represents an opportunity to incorporate large volumes of bio-carbon into transportation fuels. However, upgrading intermediate liquids from biomass and waste to final products efficiently and economically, while minimizing impacts to existing refinery infrastructure, remains a notable barrier to commercialization. The co-processing project, Bio-oil Co-processing with Refinery Streams, aimed to generate foundational knowledge for processing renewable intermediates in petroleum refineries and offer co-processing strategies, as well as develop new methods for biogenic carbon tracking and measurement.

bio-oil↗
DOE OSTI2021

Design Study for Bio-Oil Production from Biomass Using a Dual Fluidized-Bed Reactor

To evaluate the re-design and reconfiguration of a dual-fluidized bed (DFB) gasification system into a recirculating pyrolysis reactor, Computation Fluid Dynamic (CFD) simulations of the system were conducted. The Barracuda Virtual Reactor® computational particle fluid dynamic code was used to perform simulations of the pyrolysis process. Modeling of the chemical reaction kinetics for both gas phase and solid particle phase were included. The recirculating pyrolysis reactor shown in Fig. 1a is based on a bubbling-bed biomass pyrolyzer and a riser combustor to convert the remaining char. The operational differences in the re-configuration of the DFB gasification system into a recirculating pyrolysis system for the production of bio-oil are (1) replacement of a low-surface area inert bed material with a high-surface-area bed material that has acidic properties to provide catalytic activity for the production of bio-oil with reduced oxygen content, (2) lower temperature and residence time for bio-oil production from pyrolysis, (3) replacement of the fluidization gas in the bubbling bed pyrolyzer from steam to nitrogen, and (4) the reduction of pyrolyzer freeboard volume. The bed material used for catalytic pyrolysis is Sasol 300 (300-micron dia., bulk density 0.94 kg/l, and surface area 130 m2/g) and is a theta-alumina with mild acidity. This is in comparison with previous standard bed material Carbo HSP (430-micron dia., bulk density 2.01 kg/l, and surface area 0.03 m2/g) used for gasification. For bio-oil production, pyrolysis in the bubbling bed requires temperatures in the range of 550 C in comparison with gasification temperatures near 850 C. To attain this lower temperature requires management of the energy mass balances, with control of the bed material recirculation rate between bubbling bed pyrolyzer and riser combustor, the introduction of a nitrogen purge in the pyrolyzer, and adjusting the pressure balance between the two vessels. To extract bio-oil from the pyrolysis reactor with a snorkel, two different freeboard configurations were evaluated. In Fig. 1 b the existing high freeboard configuration is shown and in Fig. 1 c the reduced freeboard design is presented. The introduction of a nitrogen purge for the high free board configuration provided the highest bio-oil production from the CFD simulations. To decrease the bed-material circulation rate, primary and secondary air on the combustor side were reduced, and the pressure on the combustor was slightly increased. A portion of the biomass and bio-oil was observed to be transported to the combustor, leading to a smaller pyrolysis yield. The control of the pyrolyzer temperature is performed by controlling the circulation rate. Good fluidization of the bubbling bed and cascade PID control are required to keep the temperature from oscillating due to large time delay experienced when changing primary and secondary air. (a) (b) (c) Figure 1. (a) Dual Fluidized Bed pyrolysis system configuration, (b) mole fraction of nonpolar biooil in high freeboard configuration, and (c) mole fraction of nonpolar bio-oil in low freeboard configuration with nitrogen purge introduced in both configurations.

BASIC BIOLOGICAL SCIENCES,BIOMASS FUELS↗
DOE OSTI2019

Catalytic Upgrading of Thermochemical Intermediates to Hydrocarbons (Final Report)

A lot of activity in catalytic pyrolysis and hydroprocessing occurred in the past 10-15 years with notable successes and failures; however, very little technical information is available in the open literature from pilot-scale studies such as those performed in this project. Besides, the next step along the technology commercialization pathway is to scale-up the catalytic biomass pyrolysis process, integrate this technology with a hydroprocessing unit, and demonstrate the long-term operation and performance of the integrated process; notably, these were achieved in this project. RTI International has developed a single-step catalytic biomass pyrolysis process to produce a hydrocarbon-rich bio-crude intermediate. This bio-crude is more thermally stable and has lower oxygen content than conventional biomass fast pyrolysis oil, so it can be effectively and efficiently upgraded with traditional hydroprocessing technology to produce gasoline and diesel. Our partner, Haldor Topsøe, has developed a strategy for hydroprocessing bio-crude intermediates based on extensive catalyst and process development in support of converting vegetable oils and waste greases into high-quality diesel fuel. The goal of the originally proposed project was to demonstrate an advanced biofuels technology that integrates a catalytic biomass pyrolysis step and a hydroprocessing step to produce infrastructure-compatible biofuels. The specific technical goals of this project were 1) to optimize the catalytic biomass pyrolysis process to achieve high degree of deoxygenation, while maximizing the bio-crude production, 2) improve bio-crude thermal stability, 3) evaluate the impact of bio-crude quality in the hydroprocessing step, 4) minimize hydrogen demand of the integrated process, and 5) maximize biofuels yields. This project showed that it is technically feasible to use non-zeolitic solid acid catalyst to consistently generate bio-crude with 20% oxygen content and that these liquids can be effectively hydrotreated into low oxygen fuel blendstocks. The reproducibility of the small-scale pyrolysis yields at the 1 tonne/day scale is an achievement worth noting and the effect of pyrolysis temperature on biocrude yields and quality was investigated at the pilot scale. Additionally, advanced analytical techniques were used to analyze bio-crude to investigate the effect of process conditions and feedstock on the concentration and speciation of oxygen-containing compounds. Insights into the impact of oxygen content and oxygen speciation on bio-crdue upgrading were also sought. Clearly, more successful upgrading correlated with bio-crudes with lower oxygen content. This was most evident when partially upgraded bio-crude with 55-90% less oxygen compared to the starting bio-crude was blended with straight run diesel and hydrotreated without any noticeable increase in pressure drop across the reactor or any measurable loss of hydrodenitrification (HDN) activity. Minimizing hydrogen demand while maximizing biofuels yield are the desired outcomes for the integrated process. In summary, several technical challenges remain before catalytic biomass pyrolysis becomes a commercial reality, most notably bio-crude yields and quality still need to be improved. The integrated catalytic biomass pyrolysis hydroprocessing scheme being developed produces intermediates that can be refined for use as drop-in hydrocarbon replacement fuels. From a technology perspective, this advanced biofuel technology produces liquid transportation fuels that can leverage capital expenditures in the existing petroleum refining and distribution infrastructure. From a business perspective, this technology does not face potential market limitations as other nonhydrocarbon biofuels caused by oxygenated blending limitations and fuel certification for light-duty vehicle applications.

09 BIOMASS FUELS↗
DOE OSTI2019

Pretreatments for the continuous production of pyrolytic sugar from lignocellulosic biomass

Fast pyrolysis of lignocellulosic biomass yields little sugar or anhydrosugars compared to pyrolysis of pure polysaccharides because naturally abundant alkali and alkaline earth metals (AAEM) in biomass catalyze the fragmentation of pyranose and furanose rings. Sugar yields can be increased dramatically by pretreating the biomass with sulfuric acid prior to pyrolysis, which passivates the catalytic activity of the metals by converting them into thermally stable salts. However, depolymerization of lignin in biomass also depends on the catalytic activity of AAEM. Thus, passivating AAEM has the unintended consequence of slowing the rate of depolymerization and volatilization of lignin, resulting in a transient melt phase that agglomerates and can foul pyrolysis reactors. Here, to overcome this problem, various non-alkali metal sulfates were tested as replacements for sulfuric acid. Iron in the form of ferrous sulfate proved the most effective in depolymerizing lignin without fragmenting pyranose rings. Conventional nitrogen-blown pyrolysis of ferrous sulfate pretreated corn stover achieved WHSV of 4 h –1 compared to only 0.6 h –1 for acid pretreated corn stover. Autothermal (air-blown) pyrolysis of ferrous sulfate pretreated corn stover showed even more dramatic improvement, increasing WHSV from 1 h –1 to 10 h –1 compared to acid pretreated corn stover under autothermal operation. Fermentable sugar yields from the pyrolysis of corn stover increased from 0.9 wt% to 11.8 wt% on a biomass basis, a 13-fold increase as a result of the ferrous sulfate pretreatment. These advantages combine to increase volumetric sugar productivity from 62 g L –1 h –1 for conventional pyrolysis of untreated corn stover to 2041 g L –1 h –1 for autothermal pyrolysis of ferrous sulfate treated corn stover.

09 BIOMASS FUELS↗
DOE OSTI2024

Molten-Phase Unsaturation Enhanced Pyrolytic Upcycling of Polyolefins

Fast pyrolysis is a robust deconstruction technology for chemically upcycling waste plastics without losing significant carbon to noncondensable gases. However, fast pyrolysis of polyolefins often produces hydrocarbons with broad molecular weight distributions, mainly waxes, which can also negatively affect the commercial reactor operation and downstream upgrading of the products. We discovered that combining molten-phase thermal treatment with subsequent fast pyrolysis offers a facile method to enhance polyolefin pyrolysis and catalytic upgrading. The molten-phase thermal treatment increased unsaturated C–C bonds in the treated polyolefins. During subsequent pyrolysis, the preheated polyolefins significantly reduced wax range hydrocarbons in the condensable products without an increase in gas formation. Here, the wax yields from pyrolysis of high-density polyethylene (HDPE) preheated to 295 °C and low-density polyethylene (LDPE) preheated to 275 °C were 20.5% and 26.5%, respectively, compared to 38.6% and 46% produced from pyrolyzing untreated polyolefins. When catalytically pyrolyzed using a zeolite catalyst, the preheated polyolefins promoted higher yields of olefins during ex-situ catalytic pyrolysis and higher yields of aromatic hydrocarbons during in-situ catalytic pyrolysis. During ex-situ catalytic pyrolysis, ethylene yields were 23.3% and 24.7% for the preheated HDPE and LDPE compared to 16.7% and 9.3% for untreated HDPE and LDPE, respectively.

Aromatic compounds↗