Hydrogen Production by Glycerol Steam Reforming on the Ni/CaO-Al2O3 Catalysts: The Study of Synergistic Effect Between CaO and Al2O3

Renewable Hydrogen Production by Aqueous Phase Reforming of Pure/Refined Crude Glycerol over Ni/Al-Ca Catalysts

“…All catalysts presented a type IV isotherm with a hysteresis loop (type H2), according to the International Union of Pure and Applied Chemistry (IUPAC) classification [ 48 ], which is typical of mesoporous materials, as shown in Figure 1 A. The H2-type hysteresis loop indicates particles with an irregular structure and a non-uniform shape and size [ 13 ].…”

“…It can be used in many technologies, such as fuel cells for electricity production [ 9 , 10 , 11 ]. There are many routes to produce H 2 from glycerol, such as auto-thermal reforming (ATR, [ 10 , 12 ]), steam reforming (SR, [ 13 , 14 ]), and aqueous phase reforming (APR, [ 15 ]).…”

“…CaO has been employed as a promoter of Ni/Al 2 O 3 catalysts because of its basicity, low cost, and wide availability. It not only neutralizes the acid sites on alumina but also favors H 2 O adsorption and -OH mobility, thus accelerating carbon oxidation and inhibiting coke deposition [ 13 , 41 ]. Moreover, CaO can adsorb CO 2 during the reforming system [ 41 ].…”

“…Taking into consideration the possible presence of three impurities (methanol, acetic acid, and KOH) in crude glycerol [ 34 , 42 ] and the effect of CaO on the H 2 production studied by other authors [ 2 , 13 , 31 ], this work investigated the impact of adding Ca as a promoter in APR using crude glycerol. KOH is usually employed as a homogeneous catalyst, while methanol is used to react with triglycerides in biodiesel production.…”

Effect of Ca and Co over Ni–Al Mixed Oxides for Hydrogen Production by Ethanol Steam Reforming

“…[9] Alkaline promoters such as Ca have also been used to improve Ni-based catalysts activity, increasing H 2 selectivity and decreasing the strength of acid sites to diminish carbon deposition. [50,51] Vizcaíno et al [38] studied Ni catalysts based on ternary mixed oxides, Ni-M-Al (M = Mg, Ca, Zn) and Ni-Mg-N (N = La, Ce) with 7 wt% of Ni loading, prepared by coprecipitation using a mixture of NaOH and Na 2 CO 3 as a precipitant mixture. The characterization tests revealed that the Ni-Ca-Al catalyst included CaCO 3 and Ca 12 Al 14 O 33 in its structure, presented the lowest specific surface area before calcination, and improved Ni 2þ reducibility with a significant dispersing effect on Ni species.…”