SU448670A1 - Method of preparing catalyst for conversion of hydrocarbons - Google Patents

Description

one

The invention relates to the manufacture of catalysts for steam reforming of hydrocarbons with steam.

The mortar is a method of preparing a catalyst by mixing basic nickel carbonate, magnesium oxide, alumina with solutions of nickel nitrate and barium oxide, drying, calcining the mixture and adding calcium aluminate, filler, which uses graphite, and water, followed by granulation, - tableting, hydraulic hardening and drying.

However, with this method, the use of graphite in the tabletting process makes it difficult for the hydration reaction of calcium aluminates to proceed when the catalysts of the catheter are hydraulically cured and the catalyst is more difficult to recover. In tabletting, graphite covers the outer surface of the tablets with a thin layer, shielding the inner pores. Shielding makes diffusion of reactive molecules difficult, which slows down the process of catalyst reduction, raising the temperature of reduction to and above.

In addition, there is a significant decrease in the mechanical strength of the granules during operation due to the partial destruction of the hydration products of calcium aluminates.

In order to increase the mechanical strength of the catalyst and lower the temperature of reducing it before the process, potassium stearate is used as a filler, a solution of sulfosalicylic acid or triethanolamine is added to the mixture of components and hydraulic hardening is carried out in a solution of sulfosalicylic acid or triethanolamine. Potassium stearate is preferably administered in an amount of 0.5-2 wt.%, Sulfosalicylic acid 0.60, 75 wt.% Or triztanololamine 0.030, 45 wt.%.

Hydraulic hardening is preferably carried out in a solution containing 0.5-1.5% by weight sulfosalicylic acid or 1-2% by weight triethanolamine.

Example 1. A BZ-shaped mixer with a steam jacket is loaded with 21.5 kg of basic nickel carbonate {OH) 2-4H20, 25 kg of ground alumina and 15 kg of magnesium oxide. calcined at 12QO ° C. In 55, Q liter of hot steam condensate, 56 kg of nickel nitrate and 1.9 kg of barium oxide are dissolved. The prepared solutions are poured into a mixer and stirred with simultaneous evaporation of water for 2.5 hours to obtain a pasty mass. The latter is dried at 90-120 ° C and calcined at 380-400 ° C until complete decomposition of the salts. The resulting mixture of oxides is again charged into the mixer, 45 l of steam condensate is added and stirred with simultaneous evaporation of water to obtain a mass with a humidity of 35%. Then, 15 kg of calcium aluminate is added to the mixer, continuing the stirring and evaporation. Upon reaching a moisture content of 25%, the mass is dried at 100-120 0, after which the dried and crushed mixture of oxides is mixed with 20 kg of calcium monoaluminate, kg of potassium stearate and 10 solution containing 60 kg of sulfosalicylic acid. The mixture is compacted, pelletized and press one on a rotary tablet machine in the form of annular granules. The catalyst is first held in air, and then hydraulic hardening in a sulfosalicylic acid solution is performed.

 Mechanical strength of granules, kg / cm

Catalyst

Source catalyst

After working in a tubular reactor under the action of 30 atm, 0.6% of days, and then dried at 120C. Example 2. The catalyst is prepared analogously to example 1 with the difference that, with semi-dry mixing of the components, prior to tableting, 10 l of a solution of triethanolamine of 0.1% concentration is added to the mixture, and the hydraulic hardening of the catalyst is carried out in water containing 0.1- 0.3% triethanolamine. The resulting catalyst has a high mechanical strength. The results of testing the catalyst for mechanical strength are given in Table. 1. After 160 hours of operation under conditions of steam reforming of natural gas under a pressure of 30 atm, the residual strength of the granules is higher than that of the known catalyst. Comparative data on the test on the activity of a known catalyst and the catalyst obtained by the proposed method are given in table 2. The proposed catalyst is more active at low temperatures, it is restored by the initial vapor-gas mixture already at 400 ° C, while the known catalyst is reduced at 500 C. Table 1

Famous

650-670 Proposed 650-670

The content of residual methane in a dry converted gas, about. %

Conversion temperature, С

Famous

75-10.0

28-30

8.5-9.0

1.8-2.0

0.0-0.2

350-400 470-530

table 2

Proposed

45-55

28-30

8.5-9.0

1.8-2

0.0-0.2

Claims (3)

1. Method for preparing a catalyst for the conversion of hydrocarbons by mixing basic nickel carbonate, magnesium oxide, alumina with solutions of nickel nitrate and barium oxide, drying, calcining the mixture and adding calcium aluminates, fillers and water to it, followed by granulating, tableting, hydraulic hardening and drying, characterized in that, in order to increase the mechanical strength of the catalyst and lower the temperature of its reduction before the process, as a filler potassium stearate is used; a solution is added to the mixture of components sulfosalicylic acid or triethanolamine and hydraulic hardening is carried out in a solution of sulfosalicylic acid or triethanolamine. 2. Method POP1, characterized in that potassium stearate is introduced in an amount of 0.5-2 wt.%, Sulfosalicylic acid 0.060, 75 wt.% Or triethanolamine 0.030, 45 wt.%. 3. Method POP.1, distinguished by the fact that hydraulic hardening is carried out in a solution containing 0.5-1.5 wt.% Sulfosalicylic acid or triethanolamine 1-2 wt.%.