Advancements in membrane applications and modern analytical techniques: Pioneering principles of green and white chemistry

In the last decade, the interest in both Green Analytical Chemistry and White Analytical Chemistry has been grown by scientists and legislative authorities because of the environmental impact of traditional analytical methods. The goal of these fields is to design and implement analytical processes, as well as to develop chemicals or materials aimed to minimize the use of toxic reagents and solvents. Among the emerging sustainable separation technologies, membrane separation offers several advantages which help to reduce the resource consumption and waste generation, leading to a smaller environmental footprint and improved product purity and yield. The main conventional materials for the membrane synthesis includes organic and inorganic substances. Organic membranes are typically synthetized from rubbery or glassy polymeric materials. On the contrary, inorganic membranes are made of ceramic, glass, metals, carbon, silica, oxides and zeolites. Recently, the use of bio-based polymers represents a promising solution for the green and sustainable membranes production. These materials can be derived from different sources, such as bacteria fermentation, vegetables, and animals. Moreover, they show high hydrophilicity, biocompatibility, and biodegradability, as well as low toxicity, carbon footprint, and environmental impact. Butyrolactone, dimethyl sulfoxide, cyrene, dimethyl isosorbide, acetyltributylcitrate, methyl/ethyl lactate and deep eutectic solvents are some of the newly developed green solvents investigated. The selection is based on the affinity between solvent and polymer which defines the phase separation pathway and the performance of the resulting membranes. In line with these objectives, this chapter aims to provide an overview of the key green precursors and their application in membrane production, along with the modern analytical approaches within the contest of GAC and WAC.