The performance of Pd, Pt, Rh and Ru based catalysts in the hydrodechlorination of chloromethanes to obtain ethane and ethylene was evaluated by means of computational analysis and hydrodechlorination experiments. A computational analysis using density functional theory (DFT) was developed to obtain preliminary insight on the potential catalytic mechanisms for the reactions involved using palladium, platinum, rhodium and ruthenium metallic clusters. Stable catalytic intermediates were obtained by quantum-chemical calculations in the hydrodechlorination of dichloromethane on Pd6 and Rh6 clusters, presenting ••CH2 and •CH3 radicals and C2H4, C2H6 and CH4 products. On the contrary, it was not possible to obtain all these stable intermediates using Pt6 and Ru6 clusters. Theoretical analysis revealed lower desorption energies for ethane and ethylene products in Pd6 than in Rh6 clusters, what indicates a favorable selectivity of Pd-based catalyst for desired C2 products. Then, carbon supported catalysts containing these four metals were prepared and experimentally evaluated in the hydrodechlorination of dichloromethane (DCM) and trichloromethane (TCM) at low H2 excess and a reaction temperature range of 150-400 ºC. In agreement with computational results, in experimental tests, the Pd based catalyst showed the best performance for the hydrodechlorination of chloromethanes to obtain C2 products, followed by Rh. Ru and Pt have a poor performance, in special Pt based catalyst, which shows almost no selectivity to C2 products. This computational and experimental study emphasizes, for the first time, the good performance (high activity and selectivity) of Pd carbon supported catalysts in the valorization of chloromethane compounds to obtain C2 hydrocarbon products.

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Searching for new copper compounds which may be useful as antitumor drugs, a series of new [Cu(L-dipeptide)(batho)] (batho:4,7-diphenyl-1,10-phenanthroline, L-dipeptide: Gly-Val, Gly-Phe, Ala-Gly, Ala-Ala, Ala-Phe, Phe-Ala, Phe-Val and Phe-Phe) complexes were synthesized and characterized. To interpret the experimental IR spectra, [Cu(ala-gly)(batho)] was modelled in the gas phase using DFT at the B3LYP/LANL2DZ level of theory and the calculated vibrational frequencies were analyzed. Solid-state characterization is in agreement with pentacoordinate complexes of the general formula [Cu(L-dipeptide)(batho)]·x solvent, similar to other [Cu(L-dipeptide)(diimine)] complexes. In solution, the major species are heteroleptic, as in the solid state. The mode of binding to the DNA was evaluated by different techniques, to understand the role of the diimine and the dipeptide. To this end, studies were also performed with complexes [CuCl2(diimine)], [Cu(L-dipeptide)(diimine)] and free diimines, with phenanthroline, neocuproine and 3,4,7,8-tetramethyl-phenanthroline. The cytotoxicity of the complexes was determined on human cancer cell lines MDA-MB-231, MCF-7 (breast, the first triple negative), and A549 (lung epithelial) and non-tumor cell lines MRC-5 (lung) and MCF-10A (breast). [Cu(L-dipeptide)(batho)] complexes are highly cytotoxic as compared to cisplatin and [Cu(L-dipeptide)(phenanthroline)] complexes, being potential candidates to study their in vivo activity in the treatments of aggressive tumors for which there is no curative pharmacological treatment.

Bentonite is a claystone formed by a complex mineralogical mixture, composed of montmorillonite, illite, and accessory minerals like quartz, cristobalite, feldspars, carbonates, and minor amounts of iron oxy-hydroxides. Bentonite presents complexity at various scales: (1): a single mineral may present different chemical composition within the same quarry (e.g., feldspars solid solutions); (2): montmorillonite presents variability in the cation-exchange distribution while illite may be presented as mixed-layer with smectite sheets; and (3): hardness and crystal size are larger in accessory minerals than in clay minerals, preventing uniform grinding of bentonite. The FEBEX bentonite used is originally from Almería (Spain), and it is a predominantly calcium, magnesium, and sodium bentonite. This Spanish FEBEX bentonite has been hydrothermally altered at laboratory scale for 7–14 years. A thermal gradient was generated by heating a disk of pressed iron powder, simulating the metal waste canister, in contact with the compacted bentonite sample. Hydration was forced from the opposite direction. XRD recorded patterns were very similar. In order to minimize the bias of XRD semi-quantitative determination methods, Rietveld refinement was performed using BGMN software and different structural models. Confidence in the quantification of the main phases allows us to convincingly detect other subtle changes such as the presence of calcite in the hydration front, right at the interface between the saturated and unsaturated bentonite, or the presence of goethite, and not hematite, in the saturated bentonite, near the source of hydration. Smectite component was 72 ± 3% and the refinement was consistent with the presence of ~10% illite, comparable with previous characterizations.

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