An Improved Desulfurization Process Based on H2O2/Formic Acid Oxidation and Liquid-Liquid Extraction 2. FCC Diesel Oil Feedstocks

Abstract

Semi-empirical molecular orbital theory and parametric model 3 methods were used to calculate the quantum chemistry properties of dibenzothiophene (DBT) and its corresponding sulfone compounds to investigate the essential theory of a formic acid/H₂O₂ oxidation desulfurization system. To study oxidation kinetics of the oxidation desulfurization reaction, DBT was also employed as a model compound to obtain the oxidation kinetic parameters. Desulfurization of fluid catalytic cracking (FCC) diesel was also performed in this process, and the sulfur content was reduced from 7,200 μg·g^?1 to 598 μg·g^?1 after being extracted by polyethylene glycol 200.     

加氢精制柴油选择性氧化-萃取深度脱硫

30 %H2 O2 -HCOOH氧化加氢精制柴油 (硫含量为 794× 10 - 6 (ω) ) ,然后使用溶剂萃取氧化处理后使油品达到深度脱硫。详细考察了搅拌速度、油水两相体积比、甲酸浓度、氧化剂加量、反应温度和时间对柴油氧化脱硫的影响。同时考察了萃取溶剂含水量和萃取剂油比对脱硫及油回收率的影响。实验结果表明 :30 %H2 O2 -HCOOH生成过氧甲酸 ,能有效氧化加氢精制柴油中的有机硫化合物 ,然后经过溶剂萃取能达到深度脱硫 ;过氧化氢 /硫 (摩尔比 )为 8时 ,柴油硫含量从 794× 10 - 6 (ω)降至 87×10 - 6 (ω)。搅拌速度、油水两相体积比、甲酸浓度、过氧化氢加量、反应温度和时间对氧化脱硫均有影响。搅拌速度超过 4 0 0r/min对反应影响不明显。过氧化氢加量、反应温度和时间及萃取条件均影响油回收率。     

磷钨酸/氧化锆催化剂催化氧化柴油脱硫

采用过饱和浸渍法制备了负载型催化剂HPW/ZrO_2(HPW为磷钨酸),利用XRD、FTIR和N_2吸附-脱附方法对催化剂进行了表征。以H_2O_2为氧化剂、十六烷基三甲基溴化铵(CTAB)为相转移催化剂,对比研究了HPW和HPW/ZrO_2催化剂的氧化脱硫性能,同时考察了氧化反应条件、催化剂的循环使用性能和氧化反应动力学。实验结果表明,HPW/ZrO_2催化剂的脱硫效果优于HPW催化剂;在n(H_2O_2):n(S)=4.0、HPW/ZrO_2催化剂用量为2.5%(基于柴油质量)、CTAB用量为0.25%(基于柴油质量)、氧化温度60℃、氧化时间90 min的条件下脱硫效果最佳,柴油中硫的含量由3 647 mg/L降至72 mg/L,脱硫率达98.0%。催化剂循环使用3次后脱硫率仍达95.3%,且该氧化脱硫反应符合一级动力学。GC-SCD分析结果显示,HPW/ZrO,催化氧化法易脱除柴油中加氢法难以脱除的二苯并噻吩及其衍生物。     

用于FCC柴油氧化萃取脱硫的负载型磷钨酸催化剂和复合萃取剂

采用浸渍法制备磷钨酸(HPW)质量分数不同的半焦负载型催化剂HPW/Sc,利用扫描电镜、紫外漫反射吸收光谱和 N₂吸附-脱附分析方法表征了所制备 HPW/Sc 催化剂的结构,并在FCC 柴油的氧化萃取脱硫过程中将其作为氧化催化剂,考察了HPW 的负载量和萃取剂种类对氧化萃取脱硫率的影响。结果表明,半焦是 HPW 的良好载体,HPW 负载到半焦后保持了原有的Keggin 结构;在最优氧化反应和萃取条件下,FCC 柴油中的硫质量分数由1100 μg/g 降至89.1 μg/g, 脱硫率达到91.9%;评选出了柴油氧化萃取脱硫的专用复合萃取剂,用氢键理论和位阻效应解释了复合萃取剂可以提高回收率的原因。     

MoO3/Al2O3介孔催化剂在柴油氧化脱硫中的应用

 通过溶胶-凝胶法,以硝酸铝为铝源、蔗糖为模板剂、氨水为沉淀剂,制备了介孔 Al₂O₃,并以其为载体,等体积浸渍法制备了MoO₃/Al₂O₃介孔催化剂。采用 N₂吸附-脱附及X射线衍射对介孔 Al₂O₃和 MoO₃/Al₂O₃催化剂进行了表征。将 MoO₃/Al₂O₃催化剂用于柴油催化氧化脱硫,以 H₂O₂为氧化剂,探讨了 MoO₃负载量以及 H₂O₂用量对其催化柴油氧化脱硫的影响。结果表明,自制的 Al₂O₃载体为具有介孔结构的 γ-Al₂O₃,其比表面积、孔容、平均孔径分别为304.3 m²/g、 0.467 cm³/g 和6.14 nm。MoO₃负载量为20%(质量分数)、H₂O₂与柴油中硫的摩尔比为12、氧化温度为60℃时,柴油的氧化脱硫效果较佳,脱硫率为68.4%。     

Preliminary Research on Desulfurization of Simulated Diesel Fuel with Peroxotungstate Biquaternary Ammonium Salt/H2O2 System

Abstract

A biquaternary ammonium salt catalyst, chloride-1,4-dibenzyl-diaza-bi-cyclo [2.2.2] octane peroxotungstate (peroxotungstate biquaternary ammonium salt), was prepared, the structure of which was determined through infrared spectrometry, and was applied in desulfurization of simulated diesel fuel. Under the circumstances in which the close ion-pair of biquaternary ammonium cation and peroxotungstate anion was formed, the mechanism of phase transfer catalysis was offered with analyzing experimental process and data. The desulfurization efficiency reached 99.35% when the reaction temperature was 60°C, the reaction time was 20 min, and the molar ratio of peroxotungstate biquaternary ammonium salt to H₂O₂ was 0.015.     

H3 PW12 O40/SiO2-Al2 O3催化氧化吸附脱硫的研究

用溶胶-凝胶法制备了H3PW12O40/SiO2-Al2O3催化剂,并用于二苯并噻吩的氧化-吸附脱除实验,考察了催化剂用量、叔丁基过氧化氢用量、反应温度及反应时间对脱硫效果的影响,得出反应的最佳条件：催化剂用量为1％(W),叔丁基过氧化氢与硫的摩尔比为3,反应温度为70℃,反应时间为3h。该催化剂还能吸附二苯并噻吩的氧化产物砜或亚砜,具有良好的稳定性和再生性。     

A Study on the Oxidation-extraction Desulfurization of FCC Gasoline Over Supported Phosphotungstic Acid/H2O2/Dimethyl Sulfoxide (DMSO)

The oxidative desulfurization of FCC gasoline was investigated using HPWA/HY, HP WA/SBA-15, and HPWA/HY-SBA-15 as catalysts, individually. Micro-mesopore structured HPWA/HY-SBA-15 with 20% of phosphotungstic acid exhibited the optimal catalytical performance and the sulfur content of FCC gasoline dropped to 18 μg/g after adsorption under optimal conditions: HY content of 40% in composite zeolite and reaction temperature of 40°C for 90 min.     

超声波辐照浸渍法制备MnO2/γ-A12O3催化剂及其柴油催化氧化脱硫性能

 分别采用超声波辐照浸渍法和普通浸渍法制备了MnO₂/γ-Al₂O₃催化剂,运用电感耦合等离子体原子发射光谱（ICP-AES）和X射线衍射（XRD）对催化剂进行表征,在空气-异丁醛-MnO₂/γ-Al₂O₃体系中评价其对加氢柴油的氧化脱硫催化性能,并考察了反应温度、异丁醛用量、空气流量、溶剂类型和剂/油体积比对柴油氧化脱硫反应的影响。结果表明,超声波辐照浸渍法制备的MnO₂/γ-Al₂O₃催化剂对柴油氧化脱硫的催化性能明显优于普通浸渍法制备的催化剂。最适宜的催化柴油氧化脱硫反应的条件为：乙腈为溶剂、加氢柴油30 mL、温度35℃、异丁醛20 mmol、空气流量0.06 L/min、超声波辐照浸渍法制备的MnO₂/γ-Al₂O₃催化剂0.08 g、剂/油体积比1/6和催化氧化时间10 min。在此条件下可将柴油硫质量分数从542μg/g 降至31μg/g,柴油脱硫率和回收率分别为94.3%和93.3%。