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The first-row transition metal catalysis often serves as a complementary strategy to traditional precious metal catalysis. Other than their advantages in abundance and sustainability, their unique electronic properties often give rise to more complicated reactivities. Co-catalyzed hydrogenation is an example of these relatively underexplored first-row transition metal catalysis. In this work, we will focus on an example of Co-catalyzed hydrogenation, which was reported to be able to selectively hydrogenate C=C but not C=O. We have performed DFT calculations on the model reactions, accompanied by a series of structure and bonding analysis, to investigate the underlying reason for the observed selectivity. We have identified the predominant σ-donating nature of phosphine and the π-accepting nature of C=C/C=O fragments upon interaction with Co(I) center, and we have also analyzed why these differences would lead to different coordination geometry, stability, and reactivity. We anticipate that all these analyses would advance our understanding in Co(I) catalysis and are beneficial for future Co-based catalyst design.

Natural gas as a fuel for heavy duty applications has advantages in terms of lower CO2 and PM compared to Diesel applications. This makes operating heavy duty applications on natural gas attractive. However, in terms of aftertreatment, the challenge becomes one of controlling methane emissions over a range of vehicle operating conditions. Methane light off occurs > 400 °C and requires highly loaded precious metal catalysts (Raj in Johnson Matthey Technol Rev 60:228–235, 2016). This temperature is manageable in stoichiometric applications. However, for lean operating applications, the exhaust temperature can be below this posing a significant challenge for CH4 control. When operating lean the NOx emissions also become a challenge hence the requirement for a dedicated NOx control system. As part of the EU funded HD GAS project, an aftertreatment system was developed to meet the challenges of both NOx and CH4 control for a lean operating natural gas heavy duty engine. Fundamental studies were performed by the academic partners focusing on CH4 and NOx control, with the implementation and calibration on the engine performed by the industrial partners. This paper will discuss the steps taken from fundamental catalyst characterisation and catalyst specification to full size catalyst implementation onto a newly developed natural gas engine in order to meet Euro VI emissions legislation.

The development of new improved catalysts for the selective hydrogenation of aromatic nitrogroups is still a field of high interest for the chemical industry. Hydrogenation of aromatic nitrogroups to the corresponding aromatic amines is one of the most important applications for precious metal powder catalysts (PMPC). In this paper various commercial PMPC technologies such as palladium, platinum, platinum modified with copper and platinum modified with vanadium on activated carbon powder supports were compared to each other in regard to activity and selectivity for hydrogenation of 1-chloro-2-nitrobenzene. In this reaction, catalysts comprised of vanadium modified platinum on activated carbon showed excellent activities and selectivities towards 2-chloroaniline. Catalyst performance was affected by the ratio of platinum to vanadium and the properties of the carbon. The role of vanadium as an effective modifier to avoid accumulation of hazardous aromatic hydroxylamines was explained.

An operating company’s view of processes using PGM catalysts is, “What is the manufacturing process that will make specification product at a profit?” To evaluate those manufacturing economics, the “Precious Metal Loop” (Cline LW Jr, Precious metal recovery and the precious metal loop. Catalysis of organic reactions. Marcel Dekker Inc., New York, 1995) steps (A) buy the catalyst, (B) make the product, (C) ship spent catalyst to a refiner, and (D) receive the PGM settlement, represents that expense. This paper presents a description of each step of the loop, important values such as process losses and refining losses as a function of the metal and the metal’s ash concentration, detailed examples and a discussion to assess the manufacturing economics.

Gold catalysts of the type made in kilogram quantities by Project AuTEK are being used to demonstrate their advantages over other precious metal catalysts in achieving selectivity in both liquid- and gas-phase reactions which have commercial potential. The high activity of gold catalysts under mild conditions is a valuable asset in achieving the high selectivities.

Catalytic combustion of ethyl acetate was investigated over various CeO2-supported precious metal catalysts prepared by impregnation method, and the effect of reduction treatment on the activity was examined. Among the catalysts tested, Ru/CeO2 achieved the highest activity for ethyl acetate combustion, and the activity was almost unchanged by the heat treatment in a hydrogen atmosphere. In the cases of Pt/CeO2, Pd/CeO2, and Rh/CeO2, the catalytic activity was enhanced by the reduction treatment at 400 °C, though the activity of the reduced catalysts was still inferior to that of Ru/CeO2. It was confirmed by temperature-programmed reduction that the reduction of the ruthenium species was initiated at the lowest temperature among the CeO2-supported precious metals. The precious metal species reducible at lower temperatures should be responsible for the high activity in the complete oxidation of ethyl acetate.

Novel, Pt-only, electropositively promoted by Na, monolithic catalytic converters are developed and tested under simulated exhaust conditions within 150–500 °C. The effects of CeO2 and La2O3 additives on the novel TWC washcoat are also studied. The performance of these simple in constitution, with one precious metal TWCs, was found to be well compared to that of a commercial bimetallic (Pt/Rh)-TWC.

Catalytic combustion of volatile organic compounds (VOCs) was investigated on supported precious metal catalysts. The activities for the combustion of methane and acetaldehyde were closely related to the reducibility of the precious metal oxides of the catalysts. On the other hand, light-off temperatures for toluene combustion on PdO/Al2O3, PdO/SnO2, and PdO/CeO2 were around 200 °C, although PdO/ZrO2 showed a higher temperature of 240 °C. This result indicated that light-off temperatures depend on not only the catalytic activities but also the catalyst structure because of low concentration of toluene and weak interaction between catalysts and toluene. In this experiment, the PdO/SnO2 catalyst showed highest activity for the combustion of methane and VOCs.

The work presented in this paper was aimed at detecting, understanding and modeling some critical behavior aspects of zeolite-containing diesel catalysts. An already available mathematical model for precious metal catalysts was used as a starting point. A specially designed set of experiments provided the information needed to improve certain modeling features. New submodels were introduced to account for hydrocarbon and H2O adsorption, as well as diffusion limitations in the zeolite. The effect of flow maldistribution during real world operation was investigated experimentally and computationally. Although a number of issues (especially regarding the DeNOx mechanisms) are not yet fully resolved, significant progress was achieved as regards the understanding and computational prediction of diesel catalyst operation.

Adsorption and activation properties of precious metal clusters such as Ir, Pt, and Au toward NO were investigated by means of the density functional calculations. We focused on the geometrical features of model clusters such as the shape and the number of consisting atoms that could determine the ability for the adsorption and the activation of NO. We found that the order of the energetical stability of the adsorption states of NO can be described as Ir > Pt > Au. It depends on neither the shape of the pentaatomic clusters nor the number of atoms in the model clusters considered. The ability of the precious metal clusters for the activation of the N–O bond were also discussed from both vibrational and geometrical points of view. The substantial activation of the N–O bond was found on both the NO/Ir5 and the NO/Pt4 systems, indicating that the specific adsorption geometries enhance the ability for the activation of the N–O bond. These results indicate that the Ir cluster has the best properties for the adsorption and activation of NO.

Miniaturisation and parallelisation are fundamental strategies to enable the productivity improvements achievable by high-throughput experimentation (HTE). This paper reports how the approach has been used to allow robotic preparation of supported precious metal catalysts and parallel techniques for subsequent reaction testing. It will be shown how HTE can shorten catalyst development times through increased productivity, as well as enabling a greater diversity space to be explored than would otherwise occur.