Vorrichtung zur kontinuierlichen katalytischen Spaltung von leichtfluechtigen Kohlenwasserstoffen

摘要

In a process for the catalytic cracking with steam of volatile hydrocarbons to make a fuel gas, some at least of the steam, and the or some of any air in the reaction mixture, are heated separately of the hydrocarbon vapours to 800 DEG to 850 DEG C. in a catalyst-free zone 2 of an externally heated tube 1, the hydrocarbon vapours being separately heated only to a degree first short of thermal decomposition, the heated reaction mixture constituents being quickly mixed in a zone 9 before entering the catalyst zone 3. Steam enters at 6 and hydrocarbons, preheated e.g. to 300 DEG C., at 7, and air, if any, enters at 5. Some steam, e.g. 20% to 40% of the total, may be delivered with the hydrocarbons at 7 to control the heating thereof. The exothermic reaction in the region 10, 9 causes a rapid temperature rise there and militates against the formation of polymerizates, even at pressures of 3 to 15 atmospheres. Instead of being delivered separately, the air may be mixed with steam for delivery at 6.