液体酸法生产三甲基戊烷

Production Technology of Trimethylpentane by Liquid Acid Method

以异丁烷与丁烯为原料,液体酸硫酸/氢氟酸为催化剂,经烷基化反应生产三甲基戊烷的工艺,主要有浓硫酸烷基化法和氢氟酸烷基化法。浓硫酸烷基化法的反应条件为:反应温度3~7℃,硫酸浓度92%~96%(wt)。生产过程中,需要不断向反应器补充浓度为95%~99%的新鲜浓硫酸,并排出浓度低于90%的废硫酸,异丁烷与丁烯的投料摩尔比为12∶1~15∶1。相比单纯采用硫酸的催化剂体系,由离子液体与硫酸组成的二元混合催化剂体系,其烷基化效率提高了25%,硫酸消耗量降低60%,烷基化油品的辛烷值为97.8。氢氟酸烷基化法的反应条件为:反应温度27~43℃,氢氟酸浓度为82%~88%,投料的异丁烷与丁烯的摩尔比为12∶1~15∶1,酸烃比为4∶1,烷基化油品的辛烷值为95.2~97.4,酸耗量为0.2~0.5kg·(t油品)^-1。

Applied isobutane and butene as raw materials, sulfuric acid/hydrofluoric acid as liquid acid catalyst, trimethylpentane was produced through alkylation reaction. The main production technologies included concentrated sulfuric acid alkylation method and hydrofluoric acid alkylation method. The reaction conditions of the concentrated sulfuric acid alkylation method were as followed: the reaction temperature was 3~7℃, and the concentration of sulfuric acid was 92%~96%(wt). In the process of production, it was necessary to replenish the 95%~99% fresh concentrated sulfuric acid to the reactor, and discharged the waste sulfuric acid with the concentration less than 90%. The molar ratio of isobutane to butene was 12:1~15:1. By using the ionic liquid and sulfuric acid to form a binary mixed catalyst system, not only the alkylation efficiency of pure sulfuric acid was increased by 25%, but also the consumption of sulfuric acid was reduced by 60%. The octane number of alkylated oil was increased to 97.8. The reaction conditions of the hydrofluoric acid alkylation method were as followed: the reaction temperature was 27~43℃, the concentration of hydrofluoric acid was 82%~88%, the molar ratio of feed isobutane to butene was 12:1~15:1, the acid-to-hydrocarbon ratio was 4:1, the octane number of the alkylated oil was 95.2~97.4. The acid consumption was only 0.2~0.5 kg/t oil.