Study on solar chemical heat pump system-basic experiment on falling film reaction of 2-propanol dehydrogenation

Study on 2-propanol/acetone/hydrogen chemical heat pump: endothermic dehydrogenation of 2-propanol

“…The catalysts used in dehydrogenation of 2-propanol were nickel boride (Mears and Bourdart, 1966), nickel-"ne particles (Doi and Tanaka, 1992), Raney nickel (Kim et al, 1992), Ru/C, Ru}Pt/C and Ru}Pd/C (Doi et al, 1995;Taneda et al, 1995). Among these, Ru}Pd/C has been found to have excellent activity and selectivity in liquid-phase dehydrogenation and provides the least amount of by-products as compared to Ru}Pt/C and Ru/C (Taneda et al, 1994).…”

“…Among these, Ru}Pd/C has been found to have excellent activity and selectivity in liquid-phase dehydrogenation and provides the least amount of by-products as compared to Ru}Pt/C and Ru/C (Taneda et al, 1994). Kim et al (1992) and Doi and Tanaka (1992) have studied the e!ect of nickel catalyst on reaction rate. Kim et al (1992) used 1.76, 6.69, 21.72 and 32.0 g of Raney nickel catalyst in 500 ml of 2-propanol at a reaction temperature of 82.43C.…”

“…Their results show that the reaction rate is constant between 1.7 and 6.69 g of catalyst and that the acetone concentration in#uences the reaction rate. Doi and Tanaka (1992) used 200, 135 and 100 mg of nickel "ne particle as catalyst in 200 ml of 2-propanol at a temperature of 1003C. The maximum reaction rate of 29.79 mmol h\ g\ was obtained when the amount of catalyst was 1 g l\.…”

“…Species A}C are the working pairs and depending on their nature/characteristics, the system could be classi"ed as solid}gas or liquid}gas type of heat pump. The 2-propanol dehydrogenation/acetone hydrogenation is a liquid}gas system (Saito et al, 1987;Kim et al, 1992;Doi and Tanaka, 1992;Doi et al, 1995Doi et al, , 1997, where the endothermic liquid-phase dehydrogenation of 2-propanol ((CH ) CHOH) liberates acetone ((CH ) CO) and hydrogen (H ) selectively and rapidly at around 803C with appropriate catalysts (Mears and Boudart, 1966) such as Ru/C, Ru}Pt/C and Ru}Pd/C. The chemical reaction is…”

“…Many parameters in#uence the endothermic reaction, such as (i) the type and amount of catalyst since it is catalytic reaction; (ii) the amount of acetone in reactant mixture; (iii) the reaction temperature; (iv) the speed of the stirrer in the case of mixing batch reactor and (v) the type of the reactor. Though studies have reported the performance of 2-propanol acetone hydrogen system (Kim et al, 1992;Doi and Tanaka, 1992;Taneda et al, 1995;Doi et al, 1995;Cunningham et al, 1996;Doi et al, 1997), this article presents the results of laboratory-scale experiments on dehydrogenation of 2-propanol in the presence of 10 wt% Ru}Pt/activated C catalyst (Walaiporn, 1999). The in#uence of reaction temperature, catalyst concentration, heating temperature, amount of acetone in liquid reactant and nitrogen #ow on the reaction process have been observed and is discussed in the following sections.…”