Engineering Catalyst Microenvironments for Metal‐Catalyzed Hydrogenation of Biologically Derived Platform Chemicals

Abstract

It is shown that microenvironments formed around catalytically active sites mitigate catalyst deactivation by biogenic impurities that are present during the production of biorenewable chemicals from biologically derived species. Palladium and ruthenium catalysts are inhibited by the presence of sulfur‐containing amino acids; however, these supported metal catalysts are stabilized by overcoating with poly(vinyl alcohol) (PVA), which creates a microenvironment unfavorable for biogenic impurities. Moreover, deactivation of Pd catalysts by carbon deposition from the decomposition of highly reactive species is suppressed by the formation of bimetallic PdAu nanoparticles. Thus, a PVA‐overcoated PdAu catalyst was an order of magnitude more stable than a simple Pd catalyst in the hydrogenation of triacetic acid lactone, which is the first step in the production of biobased sorbic acid. A PVA‐overcoated Ru catalyst showed a similar improvement in stability during lactic acid hydrogenation to propylene glycol in the presence of methionine.

Rewiring Yarrowia lipolytica toward triacetic acid lactone for materials generation

“…Here, we focus on the interesting, yet simple, polyketide, triacetic acid lactone (TAL) as it is derived from two common polyketide precursors, acetyl-CoA and malonyl-CoA. TAL has been demonstrated as a platform chemical that can be converted into a variety of valuable products traditionally derived from fossil fuels including sorbic acid, a common food preservative with a global demand of 100,000 t (1,(15)(16)(17)(18). However, meeting this annual demand using the low concentrations of TAL derived from native plants like gerbera daisies (9) would require four times the quantity of global arable land.…”

Confined catalysis under two-dimensional materials

“…confined catalysis | two-dimensional materials | density functional theory | oxygen reduction reaction | graphene I n heterogeneous catalysis, active sites have long been regarded as one of the most important concepts (1)(2)(3), and, recently, the heterogeneous catalysis community has started to recognize that microenvironment around the active site is equally important (4)(5)(6)(7)(8)(9). The confined microenvironment on a heterogeneous catalyst can help to stabilize active sites and modulate chemistry at the sites, which has a significant effect on catalytic performance, similar to the role of spheroproteins in an enzyme (10).…”

Combining Metabolic Engineering and Electrocatalysis: Application to the Production of Polyamides from Sugar

“…Thet ransition from fossil to renewable feedstocks is also expected to revitalize the chemical industry by providing building blocks with new functionalities. [5] Thei deal biorefinery pipelines,from biomass to the final products,are currently disrupted by ag ap between biological conversion and chemical diversification. [3] Over the past few years,i th as become evident that building-block diversification requires the combination of biological and chemical transformations, [3b,d,4] that is,b iomass is first biologically converted by genetically engineered microbes into platform molecules that are further diversified by chemical catalysis.H owever, previous attempts to combine chemical and biological processes have led to low conversion rates owing to catalyst deactivation by residual biogenic impurities.…”

“…[3] Over the past few years,i th as become evident that building-block diversification requires the combination of biological and chemical transformations, [3b,d,4] that is,b iomass is first biologically converted by genetically engineered microbes into platform molecules that are further diversified by chemical catalysis.H owever, previous attempts to combine chemical and biological processes have led to low conversion rates owing to catalyst deactivation by residual biogenic impurities. [5] Thei deal biorefinery pipelines,from biomass to the final products,are currently disrupted by ag ap between biological conversion and chemical diversification. We herein report as trategy to bridge this gap with ah ybrid fermentation and electrocatalytic process.W ei llustrate this concept with the conversion of glucose into unsaturated polyamide-6,6 (UPA-6,6).…”