N-甲基咪唑氟硼酸盐基低共熔溶剂的制备及其氧化脱硫性能

Preparation of N-Methylimidazoliun Fluoroborate-Based Deep Eutectic Solvent and Its Oxidative Desulfurization Performance

以N-甲基咪唑氟硼酸盐([HMIM]BF 4)和苯丙酸(C9H10O2)为原料合成了[HMIM]BF 4/x C9H10O2(x=0.5、1、2)型低共熔溶剂(DESs);对其进行FT-IR、1H NMR和TGA表征分析;将[HMIM]BF 4/0.5C9H10O2低共熔溶剂作为萃取剂和催化剂、H2O2作为氧化剂脱除模拟油中的二苯并噻吩(DBT),分别考察了n(C9H10O2)/n([HMIM]BF 4)、反应温度、n(H2O2)/n(S)、低共熔溶剂的加入量和不同含硫化合物对脱硫率的影响。结果表明:在模拟油体积为5 mL、n(C9H10O2)/n([HMIM]BF 4)=0.5、反应温度为60℃、n(H2O2)/n(S)=8、反应180 min、[HMIM]BF 4/0.5C9H10O2的加入量为1.0 mL的最佳反应条件下,[HMIM]BF 4/0.5C9H10O2对DBT、4,6-二甲基二苯并噻吩(4,6-DMDBT)和苯并噻吩(BT)的脱硫率分别达98.4%、93%和89.6%;红外分析表明DBT与DESs之间存在较强的相互作用,可使DBT的结构发生畸变;在5次循环反应后,[HMIM]BF 4/0.5C9H10O2的脱硫率仍高达90.2%,表明其具有较高的稳定性。

[HMIM]BF 4/x C9H10O2(x=0.5,1,2)type acidic deep eutectic solvents(DESs)were synthesized using N-methylimidazoliun fluoroborate([HMIM]BF 4)and phenylpropionic acid(C9H10O2)as raw materials,and then these DESs were characterized by FT-IR,1H NMR and TGA.In addition,with using[HMIM]BF 4/0.5C9H10O2 deep eutectic solvent as extractant and catalyst,and H2O2 as oxidant,desulfurization was performed with dibenzothiophene(DBT)as model compound in a simulated oil system.Effects of n(C9H10O2)/n([HMIM]BF 4),reaction temperature,n(H2O2)/n(S),the amount of deep eutectic solvent and different sulfur compounds on desulfurization performance were investigated.Experimental results indicate that,under the optimum conditions(i.e.,5 mL oil volume,n(C9H10O2)/n([HMIM]BF 4)=0.5,reaction temperature 60℃,reaction time 180 min,n(H2O2)/n(S)=8,V(DESs)=1.0 mL),desulfurization ratios of DBT,4,6-dimethyl-dibenzothiophene(4,6-DMDBT)and benzothiophene(BT)are 98.4%,93%and 89.6%,correspondingly.Infrared spectroscopy analysis show there are strong interactions between DBT and DESs,which can cause DBT structure to be distorted.After 5 cycles of reaction,desulfurization ratio is still as high as 90.2%,which indicates that[HMIM]BF 4/0.5C9H10O2 demonstrates high stability.