Patent ID: 7951987

Claim:
A thermal-cracking method of hydrocarbon using a hydrocarbon thermal-cracking apparatus comprising a tube furnace including a radiation part for thermally cracking hydrocarbon feedstocks supplied together with steam and a convection part, wherein the method comprises the step of: mixing an oxide catalyst with a carrier or supporting the oxide catalyst on the carrier, wherein the oxide catalyst is represented by CrZr j A k O x , wherein 0.5≦j≦120 and 0≦k≦50, A is a transition metal, and x is a number corresponding to the atomic values of Cr, Zr, and A and the numbers of j and k, to form a hydrocarbon thermal-cracking catalyst, packing the hydrocarbon thermal-cracking catalyst in some or entire area of a tube placed in the radiation part of the tube furnace in a shape of rasching ring, partition ring, lessing ring or sponge, wherein the hydrocarbon thermal-cracking catalyst has a density of 0.5 to 3.5 g/cm 3 , a surface area of up to 50 m 2 /g and a compressive strength of at least 1000N, and wherein a heat transfer efficiency of the method is such that when a cracked gas temperature is set to at least 800° C. at an outlet of the radiation part of the tube furnace, a tube metal temperature is lowered to at least 60° C. at the outlet of the radiation part of the tube furnace, compared with when the hydrocarbon catalyst is not packed.