TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The oxygen has a purity of greater than or equal to90 wt.%. The carbon black removed is a carbon black within at least an ASTM specification for carbon blacks with respect to at least structure and surface area. The CO2, that is recovered, has a purity level of 90-99.99%.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Component: The reactor is a staged reactor. The process unit comprises an oil refinery.Preferred Property: The reactor has a combustion temperature of 2500-5500, preferably 4000-5000degreesF.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The production method further includes converting a portion of the CO gas in the product stream to carbon dioxide (CO2); removing and optionally recovering the CO2; introducing the hydrocarbon feedstock into the reactor by multi-staged additions; introducing fuel(s) into the reactor at a point prior to or where the converting is occurring, where the fuel comprises a natural gas; removing a portion of the remaining CO gas from the product stream; and transferring the product stream after the step of removing the portion of impurities to a process unit for use as a fuel or chemical feedstock. The step of converting the portion of the CO gas to CO2 includes contacting the product stream containing the CO with water or steam in a shift reactor to produce additional hydrogen gas and CO2 in the product stream. The step of removing the CO2 includes removing CO2 by processing the product stream containing CO2 through scrubber(s), pressure swing adsorber(s), membrane(s), and/or one or more acceptor materials. The hydrogen gas is purified by passing the hydrogen through one or more pressure swing adsorbers and/or one or more membranes. The method occurs without recycling the product stream to the reactor. A portion of a primary hydrocarbon feedstock is converted to carbon black downstream of where a secondary hydrocarbon feedstock is introduced into the reactor. At least 20, greater than or equal to30, greater than or equal to50, greater than or equal to60 or 25-70 wt.% of all sources of carbon being introduced into the reactor is recovered in the form of carbon black. The step of removing the portion of the impurities from the product stream includes passing the product stream through the scrubber(s) that removes sulfur containing species and/or nitrogen containing species. The vol.% of the hydrogen gas and the wt.% of carbon black in the product stream is controlled by varying the type of the hydrocarbon feedstock, type of fuel when present, ratio of oxygen to fuel when present, ratio of oxygen gas (O2) to hydrocarbon feedstock, temperature of feed gases, temperature of the hydrocarbon feedstock, the stoichiometric combustion rate, the stoichiometric carbon to hydrogen ratio in the hydrocarbon feedstock, and/or relative feed rates of oxygen, fuel and hydrocarbon feedstock. The step of converting the portion of the CO gas to CO2 occurs prior to the step of removing a portion of the impurities. It occurs during and/or after the step of removing the portion of the impurities. The amount of CO gas remains in the product stream after converting the portion of the CO in the product stream to CO2. The step of removing of the portion of the CO gas includes passing the product stream through pressure swing adsorber(s). The step of removing CO gas by the pressure swing adsorber further removes a portion of methane and/or nitrogen, which are present in the product stream as impurities. The CO gas that is removed is recycled or reprocessed through a shift reactor to convert a further portion of the CO to CO2. The method results in gaseous emissions at the location of the reactor of sulfur in gas phase species into the atmosphere of less than 5, less than 10 or less than 20 wt.% based on the total amount of sulfur fed into the method. It results in gaseous emissions at the location of the reactor of nitrogen in gas phase species into the atmosphere of less than 0.01, less than 0.1 or less than 1 metric ton/metric ton of carbon black produced. It results in gaseous emissions at the location of the reactor of carbon in gas phase species into the atmosphere of less than 10, less than 20 or less than 30 wt.% based on the total carbon fed into the method. It forms carbon black in the reactor in an amount of greater than 20, greater than 25 or greater than 30 wt.% of the product stream, based on a dry basis. A portion of the sulfur present in the hydrocarbon feedstock is removed by the formation of the carbon black and is present with the carbon black. A portion of metal present in the hydrocarbon feedstock is removed by the formation of the carbon black and is present with the carbon black. The step of removing the carbon black is achieved by cyclone or filtering and/or washing the product stream containing the carbon black with water. The process of forming the carbon black present in the product stream occurs at a carbon black manufacturing plant. The product stream after the step of removing the portion of impurities is transferred to an oil refinery. The steam is introduced in the presence of a catalytic bed.Preferred Component: The hydrocarbon feedstock comprises a primary hydrocarbon feedstock and secondary hydrocarbon feedstock(s). It has a sulfur level of greater than or equal to4 or 0.1-5 wt.% of the hydrocarbon feedstock, and hydrogen to carbon mole ratio of 0.5-3.5. The product stream, after passing the product stream through the scrubber that removes sulfur containing species, has a sulfur amount in the product stream of less than or equal to100 ppm. The impurities, excluding water (H2O), based on a dry weight basis, has an impurity content of less than or equal to1 or less than or equal to5%. The fuel and the oxygen are present in a fuel/oxygen equivalents ratio of 0-2. The product stream contains at least hydrogen (H2) and CO. The H2 and the CO are present in a mole ratio of 0.5-2 or 2-3 in the product stream prior to removing the carbon black. After the steps of converting and removing the impurities, it comprises hydrogen gas in an amount of 90-99.99 vol.% of the product stream.