use
Used to promote the conversion reaction of light oil (ie naphtha) and water vapor. Light oil is generally liquid hydrocarbons containing C8 or less. Its general formula is expressed by CnHm. The dry point of light oil used for conversion is ≤ 220 ℃. The main reactions are as follows:
CnHm nH2O→nCO [n (m/2)]H2 -Q1
CO H2O→ CO2 H2 Q2
CO 3H2→CH^[4 H2O -Q3
in addition to H2, CO and CO2, CH4 is also included in the gas generated after light oil conversion, so it needs to be converted into the second stage. CN-14 type is mainly used for the conversion of light oil to produce methane-rich gas. It can be used as a pre-conversion catalyst for light oil with higher dry point or a catalyst for light oil to produce city gas. Other catalysts are used in hydrogen production units in ammonia plants, methanol plants and oil refineries. Z409/Z405G and CZ86-1/CZ86-2 indicate that these catalysts are used in combination. In the reactor, the catalyst before the slash is placed in the upper section and the catalyst after the slash is placed in the lower section.
production method
Preparation of sintering catalyst Dissolve metal nickel with nitric acid, add light magnesium oxide to be dissolved (you can also directly use nickel and magnesium nitrate to prepare a solution), and add it to sodium metaaluminate under stirring In the solution (or neutralize the nitrates of nickel, aluminum and magnesium with a mixture of sodium hydroxide and sodium carbonate), that is, the precipitate is generated, filtered and washed, and then dried, roasted and decomposed, then a small amount of graphite and cellulose powder are added to mix evenly, tableted, crushed and pressed into a ring with magnesium stearate, and sent to high-temperature calcination to obtain an oxidized catalyst. If you want to prepare a pre-reduction catalyst (such as Z403H), you need to put the oxidation state catalyst into a reducer, and introduce hydrogen and water vapor to heat for desulfurization. Then, control a certain H2/H2O ratio and raise the temperature to about 800 ℃ for reduction. After the reduction is completed, the temperature is cooled in the hydrogen-containing gas stream, and then the hydrogen is stopped and replaced with nitrogen to obtain a pre-reduction catalyst.
Preparation of bonded catalysts Prepare a mixed solution of nickel nitrate and magnesium nitrate (some types of catalysts also add aluminum or rare earth nitrate), and neutralize nitrate with a mixed solution of sodium hydroxide and sodium carbonate to generate precipitation. Filtering, washing, drying and roasting to decompose the precipitate, and then mixed with pure calcium aluminate cement (also known as high alumina cement), potassium salt (potassium silicate aluminate double salt), graphite, etc., and pressed into rings or other shapes with a molding machine, and then cured with water or water vapor, the finished product is obtained.