催化柴油氧化与萃取脱硫过程的数学模型研究

STUDY ON MATHEMATICAL MODEL OF FCC DIESEL DESULFURIZATION THROUGH OXIDATION AND EXTRACTION

通过催化柴油氧化及溶剂萃取脱硫实验,探索了柴油脱硫率变化规律及柴油中硫化物的氧化反应机制。基于硫化物顺序氧化反应机制和溶剂萃取原理,确定了柴油脱硫数学模型和硫化物氧化速率常数模型。利用脱硫实验数据进行模型参数估值,确定了硫化物氧化反应活化能及频率因子、溶剂萃取相平衡常数等模型参数。模型预测结果表明,柴油脱硫率随着柴油氧化时间的延长先提高后降低,且脱硫率极大值随着氧化温度的降低而提高。在过氧化氢用量较少时,随着氧化溶液混合制备时间的延长,柴油脱硫率呈提高的趋势;而当过氧化氢用量较多时,柴油脱硫率呈先提高后降低的趋势。柴油脱硫率随着氧化溶液体积分数的增大先提高后趋于不变,随着萃取剂/油体积比的增大而提高。

The change trend of diesel desulfurization extent and the oxidation mechanism of organosulfur compounds in FCC diesel were examined through the experiments of diesel oxidationextraction desulfurization. Based on the series oxidation reaction mechanism of organosulfur compounds and extraction principle, the mathematical model of diesel desulfurization and the model of sulfide oxidation rate constants for different oxidative system were established. Through model parameter estimation, the activation energy and frequency factor of sulfide oxidation reaction, the phase balance constant for solvent extraction were determined by use of experimental data of diesel desulfurization. The results of the desulfurization model prediction pointed out that the degree of diesel desulfurization tended first upwards and then downwards with the extension of oxidation duration, and the peak value of desulfurization degree increased with oxidation temperature drop. In the condition of small usage amount of H2O2, diesel desulfurization degree tended upwards with the time extension of oxidation solution preparation. In opposite condition, the degree of diesel desulfurization tended first upwards and then downwards with the time extension of oxidation solution preparation. The desulfurization degree of FCC diesel tended first upwards then to be stable with the amount increase of oxidation solution, and increased with the increase of extraction solvent.