Chemical Depolymerization and Value Addition Study of Post-Consumer Polycarbonate Waste

Post-consumer plastics become an issue to the environment due to their stable and non-biodegradable nature. Their management is essential today and starts from the source of utility through segregation to the place where proper care can be taken place that includes landfills or energy recovery areas or place of recycling. The present work is a step towards the development of an environmentally friendly and sustainable depolymerization method of bisphenol A-based polycarbonate. Chemical recycling has come up with various advantages in comparison to the traditional recycling methods for plastics. The reaction has been performed with environmentally friendly green solvents and also with green reagents like alumina and montmorillonite clays.

Toward greener methods of producing branched metal nanostructures

This review highlights the use of biogenic resources (i.e., plant extracts, microorganisms, and biomolecules) as green reagents for the production of technologically promising branched metal nanomaterials.

Recent advances in green reagents for molecularly imprinted polymers

Molecularly imprinted polymers (MIPs) are tailor-made materials with special binding sites.

Glucose promoted facile reduction of azides to amines under aqueous alkaline conditions

A quick and efficient method for the reduction of azides to amines in water using d-glucose and KOH as green reagents is reported.

Isosorbide and dimethyl carbonate: a green match

In this review the reactivity of the bio-based platform compounds D-sorbitol and isosorbide with green reagents and solvent dimethyl carbonate (DMC) is reported. Dehydration of D-sorbitol via DMC in the presence of catalytic amounts of base is an efficient and viable process for the preparation of the industrially relevant anhydro sugar isosorbide. This procedure is “chlorine-free”, one-pot, environmental friendly and high yielding. The reactivity of isosorbide with DMC is equally interesting as it can lead to the formation of dicarboxymethyl isosorbide, a potential monomer for isosorbide-based polycarbonate, and dimethyl isosorbide, a high boiling green solvent. The peculiar reactivity of isosorbide and the non-toxic properties of DMC represent indeed a green match leading to several industrial appealing potential applications.

Green and energy-efficient methods for the production of metallic nanoparticles

In the last decade, researchers paid great attention to the concept of “Green Chemistry”, which aims at development of efficient methods for the synthesis of nanoparticles (NPs) in terms of the least possible impact on human life and environment. Generally, several reagents including precursors, reducing agents, stabilizing agents and solvents are used for the production of NPs and in some cases, energy is needed to reach the optimum temperature for reduction. Therefore, to develop a green approach, researchers had the opportunity to investigate eco-friendly reagents and new energy transfer techniques. In order to substitute the harmful reagents with green ones, researchers worked on different types of saccharides, polyols, carboxylic acids, polyoxometalates and extracts of various plants that can play the role of reducers, stabilizers or solvents. Also, there are some reports on using ultraviolet (UV), gamma and microwave irradiation that are capable of reducing and provide uniform heating. According to the literature, it is possible to use green reagents and novel energy transfer techniques for production of NPs. However, these new synthesis routes should be optimized in terms of performance, cost, product quality (shape and size distribution) and scale-up capability. This paper presents a review on most of the employed green reagents and new energy transfer techniques for the production of metallic NPs.