Methods for producing olefins through hydrocarbon steam cracking include passing a hydrocarbon feed that includes one or more hydrocarbons to a hydrocarbon cracking unit and passing one or more sulfur-containing compounds to the hydrocarbon cracking unit. The sulfur-containing compounds include at least hydrogen sulfide gas, and a flow rate of the sulfur-containing compounds to the hydrocarbon cracking unit is sufficient to produce a molar concentration of elemental sulfur in the hydrocarbon cracking unit of from 10 ppm to 200 ppm. The methods include cracking the hydrocarbon feed in the hydrocarbon cracking unit to produce a cracker effluent and contacting the cracker effluent with a quench fluid in a quench unit to produce at least a cracked gas and a first pygas. The first pygas has a concentration of carbon disulfide less than 50 ppmw based on the total mass flow rate of the first pygas.

A method for reducing the risk of burning and explosion in a deoxygenation process of an oxygen-containing gas includes multiple steps. According to this method, in the presence of a gaseous alkane, hydrogen reacts with an oxygen-containing gas from which an unsaturated hydrocarbon has been removed. The oxygen-containing gas contains the oxygen and the unsaturated hydrocarbon, and the content of the oxygen in the oxygen-containing gas is greater than 0.5% by volume. A gaseous alkane is introduced to reduce the risk of burning and explosion of a mixed gas. A hydrocatalytic reaction is carried out to promote oxygen in the mixed gas to react with hydrogen to produce water, which removes oxygen from the oxygen-containing gas and also effectively inhibits carbon deposition on the surface of a catalyst and the production of a carbon oxide, which enhances the toleration for fluctuation of the oxygen content in a raw gas.