A Synchrotron-Based Vacuum Ultraviolet Photoionization Mass Spectrometer-Coupled Microreactor To Probe...

Area of Science:

• Chemical Engineering
• Analytical Chemistry
• Materials Science

Background:

• Vacuum ultraviolet photoionization (VUV-PI) mass spectrometry provides isomer-selective ionization and minimal fragmentation for organic analysis.
• Investigating complex chemical systems like pyrolysis and combustion requires advanced analytical methods for real-time product identification.

Purpose of the Study:

• To develop and showcase a state-of-the-art experimental setup combining a universal catalytic microreactor with molecular beam VUV-PI.
• To investigate the thermocatalytic oxidation of exo-tetrahydrodicyclopentadiene (JP-10) over titanium-aluminum-boron reactive mixed metal nanopowder (Ti-Al-B RMNP).

Main Methods:

• Utilized a universal catalytic microreactor integrated with a molecular beam and VUV-PI mass spectrometry.
• Analyzed the thermocatalytic oxidative degradation of JP-10 fuel.
• Identified and quantified nascent gas-phase products using photoionization efficiency (PIE) curves.

Main Results:

• Identified 59 nascent gas-phase products, including oxygenated species, hydrocarbons, and radicals.
• Demonstrated a significant reduction in the critical decomposition temperature of JP-10 from 1400 K to 950 K due to Ti-Al-B RMNP.
• Showcased the capability to detect short-lived species and stable products for deciphering initial reaction steps.

Conclusions:

• The combined microreactor and VUV-PI mass spectrometry system is highly effective for characterizing hydrocarbon fuel oxidation and pyrolysis.
• This technique offers superior isomer-selective sensitivity and transient radical detection compared to conventional methods.
• The study highlights the efficient thermocatalytic activity of Ti-Al-B nanoparticles in JP-10 decomposition.