FIELD: sorbents. SUBSTANCE: method involves amines which contain (i) only carbon, nitrogen, and hydrogen atoms, (ii) one primary, secondary, or tertiary but not quaternary amino group, and (iii) tertiary nitrogen atom, at least one tertiary carbon atom or nitrogen atom directly linked to at least one secondary carbon atom. Process is carried out in absence of quaternary ammonium compound. EFFECT: simplified process. 19 cl, 7 tbl, 13 ex
