Life cycle assessment of producing emulsion-templated porous materials from Kraft black liquor - comparison of a vegetable oil and a petrochemical solvent

Including bio-sources as raw materials in a process has been widely studied to provide a positive environmental approach but it should not be the only parameter considered for greener concepts in various industries. By performing a life cycle assessment at an early stage, each phase of a given process can be analysed to identify the overall improvement of environmental efficiency. A life cycle assessment comparing two methods of preparing porous polymers from Kraft black liquor was carried out at lab-scale. The purpose of this study was to identify efficient and sustainable methods of porous materials production by determining the sources of environmental burdens. Castor oil and 1,2-dichloroethane were found to be the best solvents to produce stable black liquor emulsions. The results showed that neither of them performed the best in all environmental impact categories studied, however several trade-offs arose. Indeed, the use of castor oil in the process might be a starting point to lower global warming and acidification potential at a loss of other environmental benefits. In the case of 1,2-dichloroethane, a recycling technique was established and seemed to be a promising option in terms of environmental benefit.