Abstract: The invention concerns novel polyamines having formula (I) obtained from the reaction between a polyol diglycidylether and piperazine: in which n is a whole number between 0 and 30, R1 has different forms, R2 has formula (g5), and R2 has formula (g6) when n=0 R6: H, C1-C6 alkyl or hydroxyalkyl radical, R7: C1-C6 alkyl or hydroxyalkyl radical, R6 and R7 may be connected together to form a heterocycle having 5, 6, 7 or 8 atoms when R6 is other than H, R8: H, C1-C4 alkyl or hydroxyalkyl radical. The invention also concerns their preparation method and their use in an absorbing solution based on amines in order to selectively eliminate H2S from a gaseous effluent containing H2S and CO2.

Abstract: Method of decarbonating a hydrocarbon gas, a natural gas for example, by washing with a solvent. Said gas is contacted with an absorbent solution so as to obtain a CO2-depleted gas and a CO2-laden absorbent solution. The CO2-laden absorbent solution is then heated and expanded at a predetermined pressure and temperature so as to release a hydrocarbon-containing gaseous fraction and to obtain a hydrocarbon-depleted absorbent solution, said pressure and temperature being so selected that said gaseous fraction comprises at least 50% of the hydrocarbons contained in said CO2-laden absorbent solution and at most 35% of the CO2 contained in said CO2-laden absorbent solution. Finally, the hydrocarbon-depleted absorbent solution is thermally regenerated so as to release a CO2-rich gaseous effluent and to obtain a regenerated absorbent solution.

Abstract: The invention concerns novel polyamines having formula (I) obtained from the reaction between a polyol diglycidylether and piperazine: in which n is a whole number between 0 and 30, R1 has different forms, R2 has formula (g5), and R2 has formula (g6) when n=0 R6: H, C1-C6 alkyl or hydroxyalkyl radical, R7: C1-C6 alkyl or hydroxyalkyl radical, R6 and R7 may be connected together to form a heterocycle having 5, 6, 7 or 8 atoms when R6 is other than H, R8: H, C1-C4 alkyl or hydroxyalkyl radical. The invention also concerns their preparation method and their use in an absorbing solution based on amines in order to selectively eliminate H2S from a gaseous effluent containing H2S and CO2.

Abstract: Method of decarbonating a hydrocarbon gas, a natural gas for example, by washing with a solvent. Said gas is contacted with an absorbent solution so as to obtain a CO2-depleted gas and a CO2-laden absorbent solution. The CO2-laden absorbent solution is then heated and expanded at a predetermined pressure and temperature so as to release a hydrocarbon-containing gaseous fraction and to obtain a hydrocarbon-depleted absorbent solution, said pressure and temperature being so selected that said gaseous fraction comprises at least 50% of the hydrocarbons contained in said CO2-laden absorbent solution and at most 35% of the CO2 contained in said CO2-laden absorbent solution. Finally, the hydrocarbon-depleted absorbent solution is thermally regenerated so as to release a CO2-rich gaseous effluent and to obtain a regenerated absorbent solution.