N-甲基二乙醇胺和三乙烯四胺混胺吸收CO_2性能的研究

Absorption of CO_2 by Mixed Amine of N-Methyldiethanolamine and Triethylenetetramine

以N-甲基二乙醇胺(MDEA)和三乙烯四胺(TETA)为原料配制5种混胺总含量为30%(φ)的吸收剂用于吸收CO2,在自制的吸收/解吸实验装置中考察混胺配比和吸收剂使用次数对吸收剂性能的影响。实验结果表明,吸收剂Ⅲ(26%(φ)MDEA+4%(φ)TETA)的吸收/解吸性能最好;在101.33 Pa和298.15 K的条件下,吸收剂Ⅲ对CO2的吸收量为0.8 699 mol/mol,平均吸收速率为1.880 mmol/s;在101.33 Pa和383.15 K的条件下,吸收剂Ⅲ对CO2的解吸率为91.61%;与第1次使用相比,吸收剂Ⅲ第4次使用时,CO2吸收量降低了26.8%,CO2解吸率降低了15.7%;使用4次后,吸收剂Ⅲ的质量和p H虽有所降低,但仍具有较佳的吸收/解吸性能。

Five absorbents with 30%（φ） mixed amine which was prepared fromN-methyl diethanolamine（MDEA） and triethylene tetramine （TETA） were used to absorb CO2 in self-made absorption/desorption experimental installation. The eff ects of ratio of MAEA to TEYA in the mixed amine and using times of the absorbents on their performances in the absorption of CO2 were studied. The experimental results showed that,the absorption/desorption performances of absorbentⅢ with MDEA of 26%（φ） and TETA of 4%（φ） were the best;under the condition of 101.33 Pa and 298.15 K the total CO2absorption was 0.869 9 mol/mol and average absorption rate was 1.880 mmol/s;under the condition of 101.33 Pa and 383.15 K, the CO2 desorption rate was 91.61%. After absorbentⅢ was used four times,the total absorption was decreased by 26.8% and the CO2desorption rate was decreased by 15.7%;the quality and pH of absorbentⅢ was reduced,but it still had fairly good absorption/desorption performances.