Is Supercritical Water the Green Future of Chemical Processing? Industry stands to gain significant benefits and new opportunities

摘要

INCREASING CONCERNS about atmospheric carbon dioxide levels are spurring a rapidly growing emphasis worldwide on sustainability and circular economies(i.e.,the use of renewable materials and recycling to minimize waste and resource depletion).To reduce CO2 emissions,commercial passenger aircraft already are flying on biodiesel fuel derived from renewable plant sources converted by standard chemical processing.This quest for sustainability is prompting a move to develop matching greener nonconventional processing systems-with those based on water in a supercritical state especially attractive.This special form of ordinary water,first discovered in 1822,has remarkable solvent and heat transport properties.However,chemical engineers in industry largely have ignored it until recently.The situation now is changing with the appearance of two books.Yizhak Marcus’small(201-page)volume”Supercritical Water: A Green Solvent: Properties and Uses,”published in 2012 by John Wiley & Sons,provides all the basic data about supercritical water needed by chemical processors and explains how this amazing plasma-like material is created when ordinary water is heated above 374°C.In this condition,its solvent power resembles that of acetone.