Oxygen anion (O⁻) and hydroxide anion (HO⁻) reactivity with a series of old and new refrigerants

Abstract

The reactivity of a series of commonly used halogenated compounds (trihalomethanes, chlorofluorocarbon, hydrochlorofluorocarbon, fluorocarbons, and hydrofluoroolefin) with hydroxide and oxygen anion is studied in a compact Fourier transform ion cyclotron resonance. O is formed by dissociative electron attachment to N O and HO by a further ion-molecule reaction with ammonia. Kinetic experiments are performed by increasing duration of introduction of the studied molecule at a constant pressure. Hydroxide anion reactions mainly proceed by proton transfer for all the acidic compounds. However, nucleophilic substitution is observed for chlorinated and brominated compounds. For fluorinated compounds, a specific elimination of a neutral fluorinated alkene is observed in our results in parallel with the proton transfer reaction. Oxygen anion reacts rapidly and extensively with all compounds. Main reaction channels result from nucleophilic substitution, proton transfer, and formal H transfer. We highlight the importance of transfer processes (atom or ion) in the intermediate ion-neutral complex, explaining part of the observed reactivity and formed ions. In this paper, we present the first reactivity study of anions with HFO 1234yf. Finally, the potential of O and HO as chemical ionization reagents for trace analysis is discussed.

Direct and Real-Time Analysis in a Plasma Reactor Using a Compact FT-ICR MS: Degradation of Acetone in Nitrogen and Byproduct Formation

“…Different precursor ions may be used in positive mode (H 3 O + , ,, O 2 + , CF 3 + , C 6 H 4 F 2 ·H + , etc.) and negative mode (HO – , O – , etc.). As the ICR trap works sequentially, it is possible to switch during the same experiment between different chemical ionization precursors and even between CI and electronic ionization (EI) .…”

Insights into non-thermal plasma chemistry of acetone diluted in N2/O2 mixtures: a real-time MS experiment

“…In selected-ion flow-tube (SIFT) and drift tube (DT) apparatuses, due to the experimental conditions, HONO·H + is nearly entirely fragmented into NO + . 27–30 In our experiments, we observe both HONO·H + (63%) and NO + (37%) as we tend to find lesser fragmentation compared to SIFT or DT 22,25 (Fig. S1a and c, ESI†).…”

“…). 25 For this study, as many ions formed are oxygenated, H 3 O + was chosen as a precursor. H 3 O + is a generalist precursor whose reactivity allows for identification of a large number of oxygenated or nitrogenated VOCs.…”

Compact FTICR Mass Spectrometry for Real Time Monitoring of Volatile Organic Compounds

“…This channel is dominant with a branching ratio of 99%, with the other ion produced being H 2 OF − [ 35 ].…”