Comparison of nanoclay/polyvinyl alcohol aerogels scale production: Life Cycle Assessment

Nowadays, organic aerogels have arisen as promising materials for different applications such as: building, construction, energy among others, due to their low density, high thermal insulation capacity and high porosity. In the recent years multiple procedures to synthesize them have been developed, however, the freeze-drying method has gained more importance, being considered a cost-competitive, eco-friendly, and efficient process. Therefore, it is fundamental to evaluate its environmental impacts for its future implementation as a sustainable industrial process. In this work, a Life Cycle Assessment on the synthesis of nanoclay reinforced polyvinyl alcohol aerogels by freeze-drying has been carried out. Furthermore, the influence of the production scale (laboratory and pilot line) and the functional unit (1 kg and 1 m(3)) have been studied. Additionally, different upgrading approaches carried out in the pilot line, energy efficiency and production capacity, have been evaluated. Results demonstrated that better environmental impact values were obtained with pilot line aerogel production in comparison to laboratory scale for both functional units. Regarding the different upgrade assessment with the pilot line, it has been concluded that the background processes and the energy consumption are the main causes for the increment in the environmental impact values during the aerogel synthesis. (C) 2021 The Author(s). Published by Elsevier B.V. on behalf of Institution of Chemical Engineers.