复合催化剂合成聚甲氧基二甲醚的工艺研究

Preparation of Polyoxymethylene Dimethyl Ethers Catalyzed by Composite Catalyst

以三聚甲醛和甲醇为原料,复合型离子液体(硫酸氢根-离子液体)为催化剂合成标题化合物,气相色谱-质谱联用仪对其进行定性、定量分析。考察了催化剂种类、催化剂用量、原料配比、反应温度、反应时间和反应压力对反应的影响。结果表明:选用复合型离子液体、催化剂用量为5 wt%、m(三聚甲醛)∶m(甲醇)=1.3、反应温度100℃、反应时间4 h、反应压力2.0 MPa的条件下,三聚甲醛转化率可达96.66%。同时对合成的聚甲氧基二甲醚和20%混配的柴油进行技术指标测试,结果表明:混配后调和柴油的闪点和十六烷值有明显的提高,且符合0#柴油国标标准。

Polyoxymethylene dimethyl ethers （ PODE ） was synthesized by using trioxymethylene and methanol as raw material, composite ionic liquid as catalyst. The products were analyzed qualitatively, quantitatively via gas chromatographymass spectrometry. In the experiment, the effect of different catalysts, composite catalyst dosage, raw material ratio, reaction temperature, time, pressure were investigated. The results showed that when the reaction was carried out under the conditions of 5 wt% of catalyst, m （Trioxymethylene） ： m （ Metha- nol） = 1.3, reaction temperature 100 ℃, time 4 h, pressure 2.0 MPa,conversion of trioxymethylene was 96. 66%. At the same time, the technical specification of polyoxymethylene dimethyl ethers and 20% blending diesel were tested. As was shown by the results that flash point and cetane number of blending diesel had increased significantly, and test results were in accordance with standard of 0# diesel fuel.