Study On The Absorption Performance And Viscosity Of H₂S In PZ Promoted MDEA Aqueous Solution

In this work,the absorption capacity,H2_S loading and solution viscosities in H2_S removal process using Piperazine(PZ)promoted N-methyldiethanolamine(MDEA)aqueous solution were studied at atmospheric pressure.The temperatures were respectively 303.2K,313.2K and 323.2K.The H2_S partial pressures were respectively 300 Pa,400 Pa and 500 Pa.The mass fractions of MDEA(wMDEA)were respectively 0.300,0.400 and 0.500.The mass fractions of PZ(w PZ)were respectively 0.000,0.050 and 0.075.On the basis of experiments,the temperature and mass fraction dependences of viscosities were demonstrated and the effects of temperature,partial pressure and mass fraction of absorbent on absorption capacity,H2_S loading and apparent absorption rate were analyzed and clarified.Oue results showed that:(1)At given mass fraction of absorbent and given H2_S partial pressure,the absorption capacity of H2_S and H2_S loading decrease with increasing temperature,while the apparent absorption rate increases with increasing temperature;(2)At given temperature,given H2_S partial pressure and given w MDEA,the absorption capacity of H2_S,the H2_S loading and the apparent absorption rate increase with increasing mass fraction of PZ;(3)At given temperature,given H2_S partial pressure and given w PZ,the H2_S loading and the apparent absorption rate both decrease with increasing mass fraction of MDEA,while the absorption capacity of H2_S increases firstly and then decreases with the increase of w MDEA without PZ.However the absorption capacity decreases with the increase of w MDEA after the addition of PZ.(4)At given temperature and given mass fraction of absorbent,the absorption capacity of H2_S,the H2_S loading and the apparent absorption rate increase with increasing H2_S partial pressure;(5)The viscosity of MDEA-PZ aqueous solutions increases with increasing mass fraction of the absorbent,and decreases as with increasing temperature.