US 12,448,351 B2
Method of preparing ionic fluids
Arthur G. Mack, Conroe, TX (US)
Assigned to TETRA Technologies, Inc., The Woodlands, TX (US)
Filed by TETRA Technologies, Inc., The Woodlands, TX (US)
Filed on Nov. 27, 2023, as Appl. No. 18/519,337.
Application 18/519,337 is a continuation of application No. 17/983,873, filed on Nov. 9, 2022, granted, now 11,827,599, issued on Nov. 28, 2023.
Prior Publication US 2024/0158346 A1, May 16, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. C07D 207/04 (2006.01)
CPC C07D 207/04 (2013.01) 20 Claims
 
1. A method of preparing MEP comprising the steps of:
(a) adding N-methylpyrrolidine to an excess amount of ethyl bromide located in a reactor, wherein the N-methylpyrrolidine will react with the ethyl bromide forming MEP, wherein the reaction will have a reaction temperature that varies;
(b) stopping addition of N-methylpyrrolidine when the excess of ethyl bromide to the N-methylpyrrolidine falls within a range of 3:1 to 1.5:1;
(c) adding water to the reactor creating a two phase system to develop which includes:
(i) a top layer containing aqueous MEP and
(ii) a bottom layer containing ethyl bromide;
(d) separating the top layer from the bottom layer yielding a first aqueous solution of MEP and a second solution of ethyl bromide; and
(e) removing N-methylpyrrolidine and ethyl bromide from the first aqueous solution of MEP.