Multiscale Structure-Performance Relationships in Supported Palladium Catalysis for Multiphase Hydrogenations

The performance of heterogeneous catalysts in multiphase reactions in general is governed by different types of extrinsic and intrinsic structural effects on all length scales, i.e., on the macro- (m to cm), meso- (mm to µm), and microlevel (nm). This PhD research, with a catalysis-engineering approach, focused on several of these multiscale structure-performance relationships of supported palladium (Pd) catalysts applied in, industrially important, multiphase hydrogenations. The structure-performance relationships were studied in various batch and continuous reactors of which most are related to important topics in process intensification such a monolithic reactors and flow chemistry. The performance of monolithic Pd catalysts was enhanced by combining a new type of structured highly porous monoliths with a pressure pulse generating gas-liquid flow (i.e., Taylor flow). This induced a convective flow inside the ‘open’ monolith walls thereby enhancing the mass exchange with the Pd catalyst. This favourable result opens the avenue to higher catalyst loadings without increasing internal mass transfer limitations. Furthermore, a proof of concept study showed that a cheap and readily available gas chromatography capillary, wall-coated with an alumina-supported Pd catalyst and operated in the Taylor flow regime, can be used to synthesize high-value products and to rapidly produce (visual) information about catalytic hydrogenations. This Pd capillary flow device is an excellent alternative for expensive microchip technology and bulky round-bottom flasks. Finally, the intrinsic property of Pd to absorb hydrogen into its crystal lattice was shown to have a strong influence on its performance in the hydrogenation of aromatic nitriles. The transformation into stable Pd ?-hydride above a certain threshold hydrogen pressure induced a persistent change in activity and by-product selectivity.Chemical EngineeringApplied Science

Hypersonic airbreathing reusable advanced launcher: A feasibility study

Aerospace Engineerin

A genome-wide association study identifies a functional ERAP2 haplotype associated with birdshot chorioretinopathy

Birdshot chorioretinopathy (BSCR) is a rare form of autoimmune uveitis that can lead to severe visual impairment. Intriguingly, >95% of cases carry the HLA-A29 allele, which defines the strongest documented HLA association for a human disease. We have conducted a genome-wide association study in 96 Dutch and 27 Spanish cases, and 398 unrelated Dutch and 380 Spanish controls. Fine-mapping the primary MHC association through high-resolution imputation at classicalHLA loci, identified HLA-A*29:02 as the principalMHCassociation (odds ratio (OR) 5 157.5, 95% CI 91.6-272.6, P = 6.6 × 10-74). We also identified two novel susceptibility loci at 5q15 nearERAP2 (rs7705093;OR 5 2.3,95%CI 1.7-3.1, for the T allele,P = 8.6 × 10-8) and at 14q32.31 in theTECPR2 gene (rs150571175;OR 5 6.1,95%CI 3.2-11.7, for theAallele,P = 3.2 × 10-8). The association nearERAP2was confirmed in an independent British case-control samples (combined meta-analysis P = 1.7 × 10-9). Functional analyses revealed that the risk allele of the polymorphism near ERAP2 is strongly associated with high mRNA and protein expression of ERAP2 in B cells. This study further defined an extremely strong MHC risk component in BSCR, and detected evidence for a novel disease mechanism that affects peptide processing in the endoplasmic r