The reaction which is not associated with the middle region of blast furnace during smelting is _______ .

A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally iron, but also others such as lead or copper. With the first being that preheated blast air blown into the furnace reacts with the carbon in the form of coke to produce carbon monoxide and heat.
$2C_{(s)}+{O_2}_{(g)}\to 2C{O}_{(g)}$
All other reactions are associated with the middle region of blast furnace during smelting.The hot carbon monoxide is the reducing agent for the metal ore and reacts with the metal oxide to produce molten metal and carbon dioxide.