Hydrogenolysis of Glycerol by the Combined Use of Zeolite and Ni/Al₂O₃ as Catalysts: A Route for Achieving High Selectivity to 1-Propanol

Abstract

Sequential two-layer catalysts were used for the hydrogenolysis of glycerol to remove its oxygen content in a continuous-flow fixed-bed reactor. The acidic H-β catalyst layer was packed before the Ni/Al2O3 catalyst layer in the reactor. The sequential two-layer catalysts can provide good 1-propanol (1-PO) selectivities at high glycerol conversions (up to 69% selectivity at ∼100% conversion). To our knowledge, the catalytic system in this work presented one of the best selectivities to 1-PO using non-noble metal based catalytic systems. A preliminary mechanistic study indicated that most of 1-PO in the products was generated from glycerol via a “sequential two-time dehydration-hydrogenation” mechanism.

Efficient production of propylene in the catalytic conversion of glycerol

“…The rapid increase in biodiesel production has led to an oversupply of crude glycerol, and the effective utilization of glycerol has attracted much attention in the past decade [1,2]. Numerous efforts have been reported on the conversion of glycerol into value-added products, such as acrolein [1][2][3][4][5][6], acrylic acid [7][8][9][10], lactic acid [11,12], glycidol [13,14], hydroxyacetone (HA) [15][16][17], 1,2-propanediol (1,2-PDO) , 1,3-propanediol [36][37][38][39][40][41][42], and 1-propanol (1-PO) [43,44].…”

“…Because of the availability of 1,2-PDO from glycerol, several research groups investigated the conversion of 1,2-PDO to form 1-PO [43][44][45] and propanal (PA) [46][47][48][49]. In the hydrogenolysis of 1,2-PDO using iridium complex catalyst, Foskey et al reported that the presence of water in the reaction mixture gave improved selectivity to 1-PO, and that a 95% yield of 1-PO was achieved at 125 • C and 0.7 MPa [45].…”

Selective glycerol transformations to high value-added products catalysed by aluminosilicate-supported iron oxide nanoparticles

“…Glycerol can be converted to various fuel units through different routes such as etherification, [15][16][17] esterification, 18,19 transesterification 20,21 and hydrogenolysis. 22,23 The transformation of glycerol into fuel oxygenates by etherification and esterification methods are of special interest since they are economically beneficial to the production of glycerol by-products and biodiesel processes.…”

Vibrational Spectroscopic Characterization of Glycerol Reaction Pathways over Metal‐Modified Molybdenum Carbide Surfaces

“…The propylene produced from glycerol can contribute to the on‐purpose production to fill the current gap between propylene market demand and supply . On the other hand, the selective HDO reaction can break one or two C−O bonds of glycerol to produce value‐added C 3 oxygenates such as acetol, propanediol, and propanol . To upgrade glycerol on an industrial scale, it is necessary to design low‐cost catalysts with high stability, activity, and selectivity.…”

“…[19] On the other hand, the selective HDO reaction can break one or two CÀ O bonds of glycerol to produce value-added C 3 oxygenates such as acetol, [20,21] propanediol, [22,23] and propanol. [24] To upgrade glycerol on an industrial scale, it is necessary to design low-cost catalysts with high stability, activity, and selectivity. There have been many research efforts on the upgrading of glycerol, but spectroscopic studies on the reaction pathways and adsorbed intermediates on well-defined surfaces are still lacking.…”