This invention describes novel iron-based catalysts for conversion of carbon dioxide (CO₂) to produce valuable gases such as carbon monoxide (CO) or syngas in the presence of fuel (biomass, coal, methane) for commercial and industrial applications while reducing greenhouse gas emissions. This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.

Challenge
Syngas production from solid fuels such as biomass or coal is commercially conducted via a solid fuel gasification process. However, conventional solid fuel gasification processes are generally capital-intensive and require significant amounts of parasitic energy. Typically, the gasification process involves partial coal combustion with either O₂ or air. When air is utilized, nitrogen (N₂) may enter the syngas, diluting the syngas and making extraction difficult. When oxygen (O₂) is utilized, expensive oxygen production units tend to generate high parasitic losses. As a result, the development of alternative methods for syngas production from solid fuels are a significant area of current interest. For oxygen-based commercial solid fuel gasification, oxygen must be separated from air, which requires an air separation unit. Cryogenic air separation has been used and is very expensive. In addition, steam is also required for the process. Gasification of solid fuel with CO₂ has many advantages over conventional solid fuel gasification with oxygen/steam. 
Syngas production from methane is currently conducted via catalytic steam methane reforming and the process is energy intense with high carbon footprint. Catalytic methane dry reforming using CO₂ to produce syngas has a potential to be more economical route for syngas production.  However, the catalysts used for methane dry reforming are either very expensive or has shown poor performance stability due to catalyst deactivation. Therefore, catalyst development is important for methane dry reforming technology to be commercially viable.
 

This invention describes a pH sensor comprising an optical fiber coated with metal-oxide based pH sensing materials for use in high-temperature and high-pressure environments such as wellbores and the challenging high pH range relevant for wellbore cement. This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.

Challenge
Various fossil energy and carbon management applications require chemical composition monitoring in subsurface environments. Examples of these areas include deep and ultra-deep oil and gas resource recovery through drilling and hydraulic fracturing techniques as well as environmental monitoring in reservoirs for carbon dioxide (CO₂) sequestration. Accurate measurement of pH in subsurface wellbores is critical for early corrosion detection and wellbore cement failure prediction.
However, these subsurface environments are extremely challenging for the development and deployment of sensing technologies because of harsh conditions such as high temperatures, high pressures, corrosive chemical species, and potentially high salinity. In such harsh environments, most electrical and electronic components used in sensor applications are not feasible. Additionally, real-time monitoring of pH within cement is challenging because the high-pH range (pH ~13) can cause stability issues of commonly used pH sensing materials at high temperatures. Therefore, it is essential to develop approaches that provide stable pH sensing and that could eliminate the use of electrical components and connections at the sensing locations and avoid the common mode of failure in conventional sensors.
 

This invention describes a single-stage preparation of a novel carbon capture fiber sorbent. This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.

Challenge
Conventional pressure- or temperature-swing adsorption (PSA/TSA) processes have been widely considered for post-combustion carbon capture and direct air capture (DAC). However, the processes of pressurizing the flue gas in the case of PSA or the long regeneration time in the case of TSA are considered neither cost-effective nor energy efficient, which limit their use in large-scale carbon capture processes. Furthermore, the high heat released during carbon dioxide (CO₂) adsorption onto conventional sorbent amine sites necessitate efficient heat redistribution away from the sorbent bed and back into the overall carbon capture process. Therefore, a low-cost and energy efficient carbon capture process that could be retrofitted onto existing power plants is needed.

The invention is a family of hydrophobic, low viscosity, low vapor pressure physical solvents with molecular structures consisting of two or more alkyl-ester functional groups on a central hydrocarbon chain. These solvents have been shown to possess high carbon dioxide (CO₂) solubility and absorption selectivity, which make them well suited for the removal of CO₂ from hydrogen (H₂) produced from synthesis gas. This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.

Challenge
Future integrated gasification combined cycle (IGCC) power plants and steam methane reforming (SMR) chemical plants have the potential to reduce the cost of CO₂ capture. These power and chemical plants generate high-pressure CO₂ gas streams from the in-situ water gas shift reaction when producing H₂ used to power the electrical turbines. A variety of methods have been proposed to capture CO₂, including solvent, sorbent, and membrane technologies, with continuous solvent looping systems currently considered to be the most advanced. Precombustion capture of CO₂ is typically accomplished using physical solvents.

State-of-the-art precombustion CO₂ capture processes predominantly employ hydrophilic physical solvents. Current commercial physical solvents touted for IGCC CO₂ capture were developed for removing acid gases from raw natural gas streams. Therefore, they were designed to remove significant amounts of water from the process gas. As such, the focus was on the purification of the process gas with less concern for generation of high-purity CO₂ streams suitable for pipeline transmission and sequestration. While water removal is important for natural gas pipeline applications, it is not favorable for applications in which the fuel stream is directly combusted on-site, as would be encountered in IGCC systems.

The invention is method of fabricating a hollow glass waveguide (tube that transmits light) that exhibits low loss in the visible or short-wave spectral region and is optimized for Raman spectroscopy or visible laser beam delivery. Prior art hollow capillaries suffer high optical loss and poor visible transmission, but the NETL invention produces these high-quality capillaries via a specialized deposition system. This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.

Challenge
Currently, there are no high-quality commercially produced visible-wave hollow waveguides. Commercial vendors can produce reasonable IR hollow waveguides, but visible-range waveguides exhibit high losses and high optical noise. The patented NETL Raman Gas Analyzer requires visible-range hollow waveguides with small internal diameters (a few hundred microns) and low optical noise. No vendor could produce these waveguides, so NETL constructed this new system of waveguide fabrication. Other spectroscopic systems would benefit from better waveguides including absorption spectrometers, microscopes, sensors, etc.