Unraveling the structure and role of Mn and Ce for NOx reduction in application-relevant catalysts.

Mn-based oxides are promising for the selective catalytic reduction (SCR) of NOx with NH at temperatures below 200 °C. There is a general agreement that combining Mn with another metal oxide, such as CeOx improves catalytic activity. However, to date, there is an unsettling debate on the effect of Ce.

A strategy to convert propane to aromatics (BTX) using TiNp grafted at the periphery of ZSM-5 by surface organometallic chemistry.

The direct conversion of propane into aromatics (BTX) using modified ZSM-5 was achieved with a strategy of "catalysis by design". In contrast to the classical mode of action of classical aromatization catalysts which are purely based on acidity, we have designed the catalyst associating two functions: One function (Ti-hydride) was selected to activate the C-H bond of propane by σ-bond metathesis to further obtain olefin by β-H elimination and the other function (Brønsted acid) being responsible for the oligomerization, cyclization, and aromatization. This bifunctional catalyst was obtained by selectively grafting a bulky organometallic complex of tetrakis(neopentyl)titanium (TiNp4) at the external surface (external silanol ([triple bond, length as m-dash]Si-OH) group) of [H-ZSM-5300] to obtain [Ti/ZSM-5] catalyst 1.

Ni-Sn-Supported ZrO Catalysts Modified by Indium for Selective CO Hydrogenation to Methanol.

Ni and NiSn supported on zirconia (ZrO) and on indium (In)-incorporated zirconia (InZrO) catalysts were prepared by a wet chemical reduction route and tested for hydrogenation of CO to methanol in a fixed-bed isothermal flow reactor at 250 °C. The mono-metallic Ni (5%Ni/ZrO) catalysts showed a very high selectivity for methane (99%) during CO hydrogenation. Introduction of Sn to this material with the following formulation 5Ni5Sn/ZrO (5% Ni-5% Sn/ZrO) showed the rate of methanol formation to be 0.

A New Class of Atomically Precise, Hydride-Rich Silver Nanoclusters Co-Protected by Phosphines.

Thiols and phosphines are the most widely used organic ligands to attain atomically precise metal nanoclusters (NCs). Here, we used simple hydrides (e.g.

Compositional optimization of polyimide-based SEPPI membranes using a genetic algorithm and high-throughput techniques.

Asymmetric, nanosized zeolite-filled solvent resistant nanofiltration (SRNF) membranes, prepared from emulsified polyimide (PI) solutions via the earlier reported solidification of emulsified polymer solutions via phase inversion (SEPPI) method, were optimized for their performance in the separation of rose bengal (RB) from 2-propanol (IPA). All membranes were prepared and tested in a parallellized, miniaturized, and automated manner using laboratory-developed high-throughput experimentation techniques. Nine different synthesis parameters related to the composition of the casting solutions were thus optimized.

Solvent resistant nanofiltration: separating on a molecular level.

Over the past decade, solvent resistant nanofiltration (SRNF) has gained a lot of attention, as it is a promising energy- and waste-efficient unit process to separate mixtures down to a molecular level. This critical review focuses on all aspects related to this new burgeoning technology, occasionally also including literature obtained on aqueous applications or related membrane processes, if of relevance to understand SRNF better. An overview of the different membrane materials and the methods to turn them into suitable SRNF-membranes will be given first.

Directed development of high-performance membranes via high-throughput and combinatorial strategies.

Combinatorial strategies are for the first time applied in membrane technology and prove to be a powerful new tool in the search for novel membrane materials. The selected system for this study is a polyimide solvent-resistant nanofiltration membrane prepared via phase inversion. The phase inversion process is a typical membrane synthesis procedure involving a large number of compositional components, which can each be varied in a wide concentration range.

Porphyrin-functionalized dendrimers: synthesis and application as recyclable photocatalysts in a nanofiltration membrane reactor.

The convergent synthesis of a series of porphyrin-functionalized pyrimidine dendrimers has been accomplished by a procedure involving the nucleophilic aromatic substitution (NAS) as a key reaction step. The resulting dendritic porphyrin catalysts show high activity in the light-induced generation of singlet oxygen ((1)O2) from ground-state oxygen. These materials are synthetically useful photosensitizers for the oxidation of various olefinic compounds to the corresponding allylic hydroperoxides.

Zeolite filled polydimethylsiloxane (PDMS) as an improved membrane for solvent-resistant nanofiltration (SRNF).

Due to the shape-selectivity of the pores and the induced polymer crosslinking, zeolite filled elastomers are excellent solvent-resistant nanofiltration membranes with enhanced fluxes and retentions compared to commercial membranes, allowing use in non-polar solvents and at high temperatures.