ANALYSIS OF THE PERFORMANCE OF A PACKED BED REACTOR TO PRODUCTION ETHYL ESTERS FROM CRUDE VEGETABLE OIL USING LIPASE IMMOBILIZED IN SILICA MODIFIED WITH PROTIC IONIC LIQUID

The objective this study was to evaluated the influence of silica modified with protic ionic liquid (PIL) on an immobilized biocatalyst by covalent binding of Burkholderia cepacia lipase (BCL) in a PBR and in the transesterification reaction, by characterization and mass transfer of the system studied. The results showed that maximum conversion of ethyl esters was 39 ± 1.73% at 96 h (IB on control silica) and 47 ± 2.0% in 72 h (IB on modified silica). The PIL also influenced the analysis of residence time distribution (RTD) with the mean time ranging from 14.94 (control silica) to 25 min (modified silica). Variation of the reaction parameters (temperature, flow rate and molar ratio) positively influenced the mass transfer coefficient (kc) which varied from 0.95 × 10−4 to 2.39 × 10−4 m s−1 (IB on control silica) and from 1.22 × 10−4 to 3.06 × 10−4 m s−1 (IB on modified silica).

本研究旨在通过对所研究体系的表征与传质特性分析，评估经质子型离子液体（protic ionic liquid, PIL）改性的二氧化硅载体对以共价结合方式固定洋葱伯克霍尔德菌脂肪酶（Burkholderia cepacia lipase, BCL）所制备的固定化生物催化剂在填充床反应器（PBR）中催化酯交换反应的影响。结果表明，未改性二氧化硅负载的固定化生物催化剂在反应96 h时的乙酯最大转化率为39 ± 1.73%，而改性二氧化硅负载的固定化生物催化剂仅需72 h即可达到47 ± 2.0%的乙酯最大转化率。质子型离子液体还对停留时间分布（residence time distribution, RTD）的分析结果产生影响，两组的平均停留时间分别为未改性二氧化硅载体的14.94 min与改性二氧化硅载体的25 min。反应参数（温度、流速与底物摩尔比）的变化对传质系数（mass transfer coefficient, kc）具有正向调控作用，未改性二氧化硅负载的固定化生物催化剂的传质系数范围为0.95 × 10⁻⁴ 至 2.39 × 10⁻⁴ m·s⁻¹，改性二氧化硅负载的固定化生物催化剂的传质系数范围则为1.22 × 10⁻⁴ 至 3.06 × 10⁻⁴ m·s⁻¹。