Electro-dewatering of Cellulosic Nanomaterials

Cellulosic nanomaterials exhibit great potential in various applications due to unique properties.Abundant availability of feedstock has led to the industrialization of manufacturing processes to produce them.A significant cost-limiting factor to utilize cellulosic nanomaterials is dewatering or drying of nanocellulosic suspension.Technologies are needed to enable solid-liquid separation associated with cellulosic nanomaterials production, “as cellulosic nanomaterials are not economical to ship long distances containing significant water content”.This represents a critical driver for capital, energy, shipping, and resource costs of nanocellulose products.This program utilizes electrochemical engineering to dewater cellulosic nanomaterials while maintaining material properties when dried and redispersed.This program will design, build, and investigate electrochemical dewatering apparatus and process to achieve low cost separation of cellulosic nanomaterials and verify their structural integrity after drying and re-dispersion.Cost models will identify sub-unit operation combinations with the potential to further enable cost reductions.The projected energy costs of electro-dewatering + drying are considerably less (50% or lower) than drying alone or centrifuging + drying for cellulosic nanomaterials.Using innovative reactor designs, we demonstrated the feasibility of a costeffective, industrially viable, and energy efficient electrodewatering approach capable of 20 wt.% final solids, that could be rehydrated under vortex and confirmed for re-dispersibility.Material properties (structure, particle size) were maintained by the dewatered cellulosic nanomaterials.Implementing sophisticated electric fields, we reduced energy use by 50% compared to conventional constant voltage approaches at similar or higher dewatering performance.Phase II will begin with optimization of reactor design and electrodewatering process, to increase the solid content to 30 wt.% while lowering energy requirements and maintaining nanocellulose structural integrity.Phase II will conclude with the design, build and testing of an alpha-scale reactor, processing large volumes of nanocellulose, a Life Cycle Assessment, and a preliminary design of Beta-scale electrodewatering system for installation at a commercial partner.Benefits resulting from an electrochemical technology for dewatering cellulosic nanomaterials include: (1) development of renewable materials; (2) making strides toward long term sustainability; (3) effecting overall cost reductions in energy consumption; and (4) increasing nanocellulose use in applications including oil, gas, wastewater treatment, and electronics.Innovation in nanocellulose separations should be beneficial for industries such as cement manufacturing, paper production.A low-cost integrated solids separation technique would have a broad applicability to markets such as water purification and chemical production.