Pyrrole conversion induced pulse discharge plasma over a water surface under high-pressure argon

Electric field generated by pulsed high-voltage discharge plasma over water surface has been performed under high-pressure argon environments to oligomerize pyrrole compound. In this preliminary study, oligomerization of pyrrole in water as a reaction media and the effects of various parameters with pulsed high-voltage arc discharge plasma are studied. Such as plasma applied under hydrothermal conditions generates high-energy electrons, ions, and radicals, which in turn may generate new reaction fields, leading to effective organic compounds oxidation for both homogeneous and heterogeneous reactions. Here, we utilize pulse discharge plasma over water surface to study the removal characteristics for pyrrole into more valuable higher amines group which has been fascinating for both the industry and the scientific community. The experiments were conducted at 313 K and 1–2 MPa using a batch type reactor. Intermediate compounds from the conversion of pyrrole in the aqueous products were identified by UV–vis (ultra violet–visible) spectrophotometer and quantified using high performance liquid chromatography (HPLC). The maximum pyrrole conversion was 24.40% with a discharge plasma pressure of 2 MPa with 10,000×. It was found that pyrrole conversion can be raised considerably by increasing reaction pressure and discharge plasma amount.

► Conversion of pyrrole induced pulse discharge plasma over a water surface under high pressure argon (313 K, 1–2 MPa).
► MALDI spectrum revealed the main massed peaks to be distributed from 130 to 440 amu (pyrrole oligomers).
► The result showed that pyrrole conversion can be raised considerably by increasing reaction pressure and discharge plasma amount.