Green Approaches for Sustainable Development of Liquid Separation Membrane

Abstract

Water constitutes one of the basic necessities of life. Around 71% of the Earth is covered by water, however, not all of it is readily available as fresh water for daily consumption. Fresh water scarcity is a chronic issue which poses a threat to all living things on Earth. Seawater, as a natural resource abundantly available all around the world, is a potential water source to fulfil the increasing water demand. Climate-independent seawater desalination has been touted as a crucial alternative to provide fresh water. While the membrane-based desalination process continues to dominate the global desalination market, the currently employed membrane fabrication materials and processes inevitably bring adverse impacts to the environment. This review aims to elucidate and provide a comprehensive outlook of the recent efforts based on greener approaches used for desalination membrane fabrication, which paves the way towards achieving sustainable and eco-friendly processes. Membrane fabrication using green chemistry effectively minimizes the generation of hazardous compounds during membrane preparation. The future trends and recommendations which could potentially be beneficial for researchers in this field are also highlighted.

Semi-continuous and continuous processes for enantiomeric separation

“…Fortunately, some researches indicate that it is completely possible to achieve these goals with greener solvents, not yet now but very soon. 262 Moreover, the treatment and recycling of the used organic solvents may be a viable approach to reduce waste.…”

Waste Reutilization in Polymeric Membrane Fabrication: A New Direction in Membranes for Separation

“…While the reutilization of bio-based waste as polymeric raw material is expected to bring down the unfavourable effects of engineering polymers to certain extent, the use of green solvent in the dissolution of solid waste-derived raw material during membrane fabrication is also imperative to maximize the process sustainability. A number of studies have demonstrated the feasibility of green solvent or the less toxic solvent in the preparation of polymer dope solution [169]. It is worth noting that, although IL has been well recognized as a versatile green solvent due to its high dissolution capacity and recyclability, the current production cost of ionic liquid is still the major hindrance for its commercial viability.…”

Green and Non‐Conventional Materials for Membrane Synthesis: A Review

“…These solvents are deadly to both humans and the environment [2] . Most of these solvents are reported to cause eye, skin and respiratory irritation [3] . They affect aquatic life and are suspected to be carcinogenic.…”

“…They affect aquatic life and are suspected to be carcinogenic. Many of them are known to cause reproductive disorders in humans [3] . N‐Methyl‐2‐Pyrrolidone (NMP) happens to be the most used solvent for membrane preparation.…”

“…Many of them are known to cause reproductive disorders in humans. [3] N-Methyl-2-Pyrrolidone (NMP) happens to be the most used solvent for membrane preparation. As of May 2020, the European Union has restricted its usage.…”