Block copolymers, synthesis and application as dehydrating and desalting of heavy crudes

A method of dewatering and desalting crude oil, comprising:

• mixing a dewatering and desalting agent and a crude oil having a specific gravity of about 14 to 23° API at a concentration of at least 100 ppm, wherein said dewatering and desalting agent comprises at least one compound selected from the group consisting of Formula 1 and Formula 5;
• where R is
• and R represents a copolymer with a molecular weight in the range from 1000 to 4000 Daltons,
• w and v are independently a whole number consistent with the molecular weight,
• R1, R2 and R3 radicals are independently selected from the group consisting of —CH2(CH2)AB;
• —CEGJ;
• —CH2CHLM;
• —CH2(CH2)QM;
• where A is a number between 1 and 9, B is H,
• E, G and J are a radical independently selected from the group consisting of:—H, methyl, ethyl, n-propyl, iso-propyl, sec-butyl, iso-butyl, tert-butyl, n-butyl, phenyl, cyclohexyl, and cyclopentyl,
• L is a radical represented by methyl or ethyl, and M is a hydroxyl group,
• O is a number between 1 and 5, T is represented by groups E, G and J, NO2, Cl, F and Br;
• and
• Z is a radical independently selected from the group consisting of methanesulfonate, benzenesulfonate and para-toluenesulfonate.