Industrial gas mixtures — composition of producer gas Producer gas made by blowing air (and sometimes steam) over hot coke or coal contains primarily which components?

Introduction / Context:
Producer gas is a low-calorific fuel gas historically used for heating and power generation. Its composition reflects air-blown partial oxidation and, when used, steam reactions in the generator.

Given Data / Assumptions:

• Air-blown gasification over incandescent coke/coal.
• Main reactions: partial oxidation and water–gas reactions.

Concept / Approach:
Air provides nitrogen, which dilutes the gas. Carbon reacts to form CO and some CO2. If steam is used, the water–gas reaction increases H2 and CO. Methane is minor in producer gas; acetylene is not a stable bulk product of this process.

Step-by-Step Solution:
List expected components: significant N2, CO; some H2; some CO2.Match to choices: “CO, CO2, N2, H2” is the only option containing all principal species.

Verification / Alternative check:
Typical producer gas analysis: CO ~20%, H2 ~10–15%, CO2 a few percent, balance N2, traces of CH4.

Why Other Options Are Wrong:

• CO, H2 only: omits dominant N2 and CO2.
• H2, CH4: not representative; CH4 is low.
• C2H2, CO2, H2: acetylene is not a primary component.

Common Pitfalls:

• Confusing producer gas with water gas (steam–carbon) or syngas from oxygen-blown units (which has little N2).

Final Answer:
CO, CO2, N2, H2