*3.1.1 Synthesized from biomass*

MeOH can be synthesized industrially from biomass like plants, fruits and animal wastes through anaerobic metabolism by many bacteria. Also, methanol was formed as a by-product during the ethanol fermentation process. Moreover, mainly in China and South Africa methanol can be produced from coal because of majority coal deposits was found in both countries and throughout the world. Most of the industrialists preferred for synthesis of MeOH from biomass due to process simplification, reduction of cost and energy consumption. The production scheme of methanol [10] was given in **Figure 2**.

### *3.1.2 Methanol from catalytic synthesis*

The reactions relevant for the production of methanol have been known for a longtime. A mixture of CO2, CO and H2 can react with each other to form methanol and water as a byproduct. Equations (1) and (2) show the stoichiometry of these reactions and their reaction enthalpy [11].

$$\text{C}\bullet \text{ } \text{2H}\_{2} \oplus \text{CH}\_{3}\text{OH} \quad \Delta \text{H}\_{298.15\text{ K}, 5\text{MPa}} = -\text{90.7\text{ kJ}}\text{mol}^{-1} \tag{1}$$

*Alcohol Fuels as an Alternative Fuels - Bringing New Heights in Sustainability DOI: http://dx.doi.org/10.5772/intechopen.86626*

**Figure 2.** *The schematic representation of methanol production [10].*

$$\text{CO}\_2 + \text{NH}\_2 \leftrightharpoons \text{CH}\_3\text{OH} + \text{H}\_2\text{O} \quad \Delta \text{H}\_{298.15\,\text{K},\text{SMPa}} = -90.7\,\text{kJ}\,\text{mol}^{-1} \tag{2}$$
