	US 11,753,361 B2
	Method of isolation of ARN acids from naphthenate deposits
Valdemar Lacerda Junior, Vila Velha (BR); Eliane Valeria De Barros, Vila Velha (BR); Alvaro Cunha Neto, Vitoria (BR); Wanderson Romao, Vitoria (BR); Cristina Maria Dos Santos Sad, Sera (BR); Paulo Roberto Filgueiras, Vitoria (BR); Eustaquio Vinicius Ribeiro De Castro, Vila Velha (BR); Luiz Silvino Chinelatto Junior, Rio de Janeiro (BR); Juliana Navarro Bertelli, Vitoria (BR); and Rogerio Mesquita De Carvalho, Rio de Janeiro (BR)
Assigned to PETROLEO BRASILEIRO S.A.-PETROBRAS, Rio de Janeiro (BR); and UNIVERSIDADE FEDERAL DO ESPIRITO SANTO-UFES, Vitoria (BR)
Filed by PETROLEO BRASiLEiRO S.A.—PETROBRAS, Rio de Janeiro (BR); and UNIVERSIDADE FEDERAL DO ESPIRITO SANTO—UFES, Vitoria (BR)
Filed on Dec. 9, 2021, as Appl. No. 17/546,373.
Prior Publication US 2022/0177400 A1, Jun. 9, 2022
Int. Cl. C07C 51/02 (2006.01); C07C 51/48 (2006.01); B01D 15/42 (2006.01); B01D 15/36 (2006.01); C07C 51/47 (2006.01)

CPC C07C 51/02 (2013.01) [B01D 15/361 (2013.01); B01D 15/426 (2013.01); C07C 51/47 (2013.01); C07C 51/48 (2013.01)]

6 Claims

1. A method for isolating high molecular weight, tetraprotic naphthenic acids (ARN acids) from naphthenate salt deposits formed during petroleum production, comprising the steps of:

(i) cleaning the naphthenate salt deposit to remove residual crude oil;

(ii) converting a portion of the naphthenate salts to naphthenic acids; and

(iii) isolating the ARN acids from the naphthenic acids, wherein step (iii) comprises using an ion exchange mechanism to isolate the ARN acids from the naphthenic acids by exposing the naphthenic acids to an aminopropyl group-functionalized, silica-based sorbent material; and eluting the ion exchange mechanism with eluents to collect the naphthenic acids in separate eluates according to differences in polarities and as a function of molecular weights, wherein at least one of the eluates comprises ARN acids.