Executive Summary : | Recently, n-butanol has received great attention in the bio-fuel sector due to its prominent fuel properties, and therefore the demand for n-butanol is being drastically increased in the present scenario. The catalytic conversion of bio-ethanol has been considered as a potential route for the production of n-butanol. The conversion of ethanol to butanol process generally involves three reactions namely dehydrogenation, aldol-condensation followed by hydrogenation, therefore metal functionalized solid-acidic-basic catalysts (M/MgO-Al2O3) have been tremendously used for this conversion, where metal function is responsible for the hydrogenation and dehydrogenation reactions, while acidic-basic functions are responsible for the aldol-condensation reaction. However, this process has certain limitations i.e. (i) ethanol conversion towards n-butanol was very low (25%) due to the lack of appropriate active metal sites and insufficient balance between acidic and basic sites in the catalysts, and (ii) conversion of ethanol into n-butanol reaction is mostly conducted in the liquid phase system under harsh reaction conditions resulting in decrease of process economy as it requires high energy and special effort for separating products. To overcome these issues, in the present study, we are going to adopt the certain important strategies i.e. (i) the optimization of MgO and Al2O3 ratio and (ii) adding of suitable hydrogenation/dehydrogenation metals such as Zn, Ni, Fe, Cu etc. along with promoters like La, Ce, Zr, Si, activated carbon etc. to MgO-Al2O3 support to increase the conversion of ethanol (more than 30%) towards n-butanol. Further, conducting reaction in a fixed bed reactor set up can be a best solution for solving the issues arrived from the liquid phase reaction conditions (parr reactor), as it is very easy for separating formed product mixture and scaling-up studies towards commercialization. The crux of the present study is to develop an efficient process operating heterogeneous catalyst possessing appropriate acidic-basic and active metal sites to achieve high conversion of ethanol (more than 30%) towards n-butanol at vapor phase reactor setup under mild reaction conditions. The overall process addresses the sustainable development goals (SDGs) of Govt. of India related to petroleum-imports substitution, Atmanirbhar Bharat and make India by the way of providing a green process for the production of advanced bio-fuel (n-butanol) from ethanol. The conversion of bio-ethanol into advanced bio-fuel not only increases the fuel efficiency of bio-ethanol but also improves the overall economy of the bio-ethanol production process as n-butanol fuel features are similar to commercial gasoline. |