Ethylene cracking C6-C8 distillate oil hydrorefining method

Abstract

The invention relates to an ethylene cracking C6-C8 distillate oil hydrorefining method, which is characterized in that a heat insulation bed reactor is used; a nickel and molybdenum series catalyst is vulcanized by vulcanizing oil and then put into raw material oil; the catalyst uses molybdenum, cobalt, nickel and potassium as active ingredients; silicon oxide-aluminum oxide is used as a carrier;through being metered by the total weight of the catalyst, the catalyst contains 6 to 22 percent of molybdenum oxide, 0.1 to 2.2 percent of cobalt oxide, 4.0 to 8.2 percent of nickel oxide, and 0.1 to 3.0 percent of potassium oxide, and 75 to 88 percent by weight of the silicon oxide-aluminum oxide carrier. The reaction process conditions are as follows: the reaction pressure is 2.8MPa or higher;the inlet temperature is 220 to 380 DEG C; the volume space velocity of fresh raw material oil is 1.5 to 3.5h<-1>; through being metered by the fresh oil, the volume ratio of hydrogen to oil is from(180:1) to (350:1). The catalyst is good in anti-colloid capability; the arsenic resistance, sulfur resistance and water resistance capabilities are strong; the stability is good.

Description

technical field [0001] The invention relates to the field of oil refining and chemical industry, and is a second-stage C pyrolysis gasoline 6 -C 8 Distillate oil hydrorefining method. Background technique [0002] With the improvement of ethylene production capacity, ethylene by-product pyrolysis gasoline also increases, and pyrolysis gasoline includes C5-C10 fractions. In the prior art, two-stage hydrogenation technology is generally used for the treatment of pyrolysis gasoline fractions. The first stage of pyrolysis gasoline is selective hydrogenation, and the purpose is to generate active components (such as alkynes, diolefins and alkenyl aromatics) therein. Corresponding monoolefins and alkyl aromatics, use noble metal hydrogenation catalysts or non-noble metal Ni-based catalysts to saturate these active unsaturated components in oil products at lower temperatures to reduce coking in the second-stage catalyst bed, thereby To ensure the operating cycle of the device, t...

AI Technical Summary

Problems solved by technology

CN1353168A discloses a catalyst suitable for the second-stage hydrofining of pyrolysis gasoline and its preparation method. The alumina precursor is used to add a high polymer and the IV subgroup metal to obtain a molded carrier after drying and roasting. Immerse in ammonia co-impregnation solution containing Mo, Co, and Ni active components, dry at 100-120°C, and activate at 400-700°C in air to obtain a catalyst, which can adjust the acidity and alkalinity of the carrier and inhibit the coking and deactivation speed of the catalyst. The low specific surface area of ​​the carrier leads to low hydrogenation activity of the catalyst

And pyrolysis gasoline when using Al 2 o 3 When used as a carrier, in the process of reducing nickel ions at high temperature, it is easy to cause the formation of nickel aluminate, thereby reducing the catalyst activity selectivity and poor catalyst stability