Cu-Based Catalysts Show Low Temperature Activity for Glycerol Conversion to Lactic Acid

Abstract

Cu based catalysts with a base promoter are reported for the first time for the synthesis of lactic acid from glycerol without using either a reductant or an oxidant. The catalytic route presented here gives high yields at lower temperatures (473 K) and lower molar NaOH/glycerol ratios (1.5) compared to the known hydrothermal (553−573 K) route. Further, the Cu2O catalyst shows excellent recyclability.

Hydrothermal conversion of high-concentrated glycerol to lactic acid catalyzed by bimetallic CuAux (x = 0.01–0.04) nanoparticles and their reaction kinetics

“…[17][18][19] The interaction between Au and Cu played an important role for the formation of lactic acid from glycerol.…”

“…Recently, the conversion of glycerol to lactic acid over Cubased catalysts [17][18][19] with a lower cost and a high catalytic activity was investigated. When the hydrothermal conversion of glycerol (1.1 mol L À1 ) in a NaOH aqueous solution was carried out at 240 C for 6 h, the lactic acid selectivities of 79.7%, 78.6%, and 78.1% at the glycerol conversions of 75.2%, 97.8%, and 93.6% were obtained using Cu/SiO 2 , CuO/Al 2 O 3 , and Cu 2 O as catalysts, respectively.…”

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].…”

Oxidation of Glycerol with Unactivated Electroless CuNiMoP Catalyst

“…In the course of this experiment, it was observed that glycerol oxidation on the 60-min CuNiMoP/Al 2 O 3 yielded lactic acid as suggested in Scheme 1. According to [24], glyceraldehyde is dehydrated to produce 2-hydroxypropenal, which undergoes keto-enol tautomerization to give pyruvaldehyde, which, through benzylic acid arrangement, is converted into lactic acid [24].…”