Sustainable Chemistry

Fluoropolymers, notably poly(vinylidene fluoride-co-hexafluoropropylene) (PH), are rendered to be an excellent choice for superior performance coatings attributed to their exceptional mechanical robustness, thermal resistance, and resistance to chemical attack. However, their low surface energy results in poor adhesion to metal substrates, limiting their application in critical corrosion-resistant systems. To address this challenge, PH was hydroxyl-modified (PHOH) to introduce active functional groups that enhance bonding capabilities.

Amine-based adsorbents are widely used for CO2 capture. However, one of the biggest hurdles for their further development is their limited oxidation stability. Moreover, methods developed to improve the oxidation stability often lead to significant decrease in their CO2 (HES) on the CO2 uptake. Here, we investigated the effect of hydroxyethyl starch uptake and oxidation stability of impregnated polyethylenimine (PEI) adsorbents. Performance of HES-PEI co-impregnated materials was evaluated under different oxidation conditions using CO2 uptake measurements, and mass spectrometry.

Peptoids, or N-substituted glycine polymers, are an important platform for the development of new materials for therapeutic, cryopreservation, and biosensing applications. The stepwise solid-phase synthesis of peptoids uses iterative acylation and displacement reactions to grow the peptoid chain but relies on hazardous solvents, N,N-dimethylformamide (DMF) and N-methyl-2-pyrrolidone (NMP), which are used in large quantities for resin swelling, washing, and solubilizing the required chemical reagents.

Chemistry knowledge is essential in addressing solutions to complex global challenges such as achieving the United Nations’ Sustainable Development Goals. However, current teaching methods in chemistry often lack connections to global issues; without explicit practice and assessment, students cannot be expected to make these connections. Systems thinking (ST) has been proposed as part of an approach that aims to examine complex phenomena from a holistic perspective to prepare future scientists for the work needed to address these emerging global issues. 

Glycerol hydrogenolysis allows to obtain lots of value added compounds, that, when the reactive comes from renewable sources such as a by-product of the biodiesel industry, it becomes the product renewable too. Each one of the possible product are aligned with the green engineering concept as they are sustainable and contribute to the green supply chain. Glycols, specically propyleneglycol, is an already known and proven molecule, which can be easily introduced into the market without any constrain.  

In recent years, Palladium (Pd) catalysis has expanded to the use of metallic nanoparticles (NPs), due to their physicochemical properties that are related to catalytic activity. In particular, C-H bond activation reactions catalyzed by Pd attract interest because they can generate new C-C bonds without the need for prior functionalization, shortening synthesis steps and reducing waste generation. An example is phenanthridin-6(5H)-ones and benzo[c]chromenes, which are heterocycles present in various natural products and with important biological activities.

Over the past two decades, there has been a significant surge of interest in the field of ultraviolet and/or visible (UV/vis) light photocatalysis. UV-vis irradiation merged with noble metal-based photosensitizers of Ru, Ir as catalysts is most useful combination in this segment as these metal photocatalysts mostly absorb in the UV/vis region. However, high energy UV/vis irradiation sources as well as the noble-metal based photosensitizer are not considered as green.

Supported metallic and bimetallic nanocatalysts were synthesized and characterized. They were employed in different steps of the synthesis of a variety of bioactive compounds, taken in place the high atom economy and the sustainability of the process. The recoverability and reusability of the nanocatalysts was studied. The nanocatalyst were used particularly in C-H activation reaction, through a cross dehydrogenative coupling reaction (CDC), to form new C-C and C-heteroatom bonds.