缓和加氢分离轮古常压渣油正庚烷沥青质中的钒化合物

THE ISOLATION OF VANADIUM COMPOUNDS FROM HEPTANE ASPHALTENE OF LUNGU ATMOSPHERIC RESIDUE BY MILD-HYDROGENATION

采用缓和加氢方法处理轮古常压渣油(LGAR)正庚烷沥青质,并用溶剂萃取方法分离缓和加氢后的正庚烷沥青质中的金属钒化合物,采用紫外-可见分光光度(UV-vis)法和基质辅助激光解吸电离飞行时间质谱(MALDI-TOFMS)法分析萃取得到的钒化合物的存在形态,也考察了缓和加氢后水相中的钒化合物的存在形态。结果表明,硼氢化钠-氯化钙体系以四氢呋喃为溶剂的缓和加氢反应能够从LGAR正庚烷沥青质中脱除出较多的钒化合物,并且反应温度越高,脱除出的钒化合物越多;脱除的钒化合物主要分布在水相中。缓和加氢后的沥青质中的钒化合物类型是初卟啉(ETIO),其相对分子质量比未经缓和加氢脱除的钒化合物大,而水相中的钒主要以V4+的形式存在。

The solvent extraction was used to isolate vanadium compounds from Lungu atmospheric residue （LGAR） heptane asphaltene which were treated by mild-hydrogenation methods. Then the vanadium compounds were characterized by ultraviolet-visible spectrophotometry （UV-vis） and matrix assisted laser desorption/ionization time-of-flight mass spectroscopy （MALDI-TOF MS）, and the conformation of vanadium species in water phase after mild-hydrogenation was also speculated. It was found that by using the mild-hydrogenation in the combined reagent NaBH4-CaCl2 system the vanadium compounds could be isolated from LGAR heptane asphaltene, and the higher the reaction temperature, the more the isolated vanadium compounds, and the isolated vanadium compounds existed in water phase. The vanadium compounds isolated from LGAR heptane asphaltene after mild-hydrogenation were mainly vanadium etioporphyrins （ETIO）, whose molecular mass was bigger than that of the vanadium porphyrins in heptane asphaltene before mild-hydrogenation. The vanadium species in water phase mainly existed in V^4＋.