Temperature Effect on Pretreatment of the Activated Carbon Support (Pt/AC and Pd/AC) for Glycerin into Lactic Acid

Abstract

This study evaluates the influence of the presence of oxygenated groups created onto the surface of activated carbon (AC) on its ability to disperse platinum (Pt) or palladium (Pd) particles and on its catalytic performance to drive the transformation of glycerol into lactic acid. AC pretreatment consisted of oxidation in the presence of HNO3 aqueous solutions conducted at 50, 70, and 90 °C, aiming at creating oxygenated groups on the support surface. The catalytic activities of Pt/AC and Pd/AC catalysts were evaluated in the production of lactic acid from both glycerol and crude glycerin. Lower-temperature pretreatments provided catalytic supports showing higher metal uptakes together with similar catalytic activity conversion and yield for both metals (5% Pt/AC and 10% Pd/AC). The catalysts were stable in five reaction cycles, and only negligible activity loss was detected.

The support influence of Au‐based catalysts in glycerin selective oxidation to glyceric acid

“…By rough estimation, the particle size of Au NPs is below 5 nm; nevertheless, some Au NP aggregation was observed in each catalyst (Fig. 3(a−c)) 27‐29 …”

“…3(a−c)). [27][28][29] XPS spectra of Au 4f in fresh and spent 5% Au/HT, 5% Au/HAP, and 5% Au/CuO catalysts are shown in Fig. 4.…”

Production of Levulinic Esters by Heterogeneous Catalysis with Zr Metal–Organic Frameworks in Pressure Reactors

“…The Multipack software version 9.6.0.15 was employed to analyze in detail the recorded spectra. The obtained spectra were fitted using Gaussian–Lorentzian curves to more accurately extract the binding energies of the different element core levels …”

“…The obtained spectra were fitted using Gaussian−Lorentzian curves to more accurately extract the binding energies of the different element core levels. 43…”

Dehydrogenation of Glycerol for CO2 Reduction in One‐Pot Production of Lactic Acid and Formic Acid with Ru‐MACHO

“…According to the current literature, there are many catalysts used to convert glycerol into LA, such as Pt/ZrO 2 , [8,9] Au−Pt/TiO 2 , [10] Pt/AC [11] and other noble metal supported catalysts [12,13] . However, their further applications are limited due to the scarcity of precious metals.…”