Asymmetric Cellulosic Membranes: Current and Future Aspects

In this paper, we report our attempt to elaborate on cellulose-based materials and their potential application in membrane science, especially in separation applications. Furthermore, the cellulosic membrane has received attention for potential use as biomaterials such as novel wound-dressings and hemodialysis materials. In this mini-review, we mainly focus on the separation and antimicrobial properties of cellulosic membranes and the advanced synthesis/processing methods for superior functional quality for various potential applications. Finally, we conclude with the market and the impact of developments of future expectations.

Sustainable Alkaline Membrane Fuel Cell (SAMFC)

This work addresses the development and construction of a sustainable alkaline membrane fuel cell (SAMFC). The SAMFC couples an alkaline membrane fuel cell (AMFC) with a hydrogen generation reactor that uses recycled aluminum from soda cans to split the water molecule through the oxidation of aluminum catalyzed by sodium hydroxide. An innovative cellulosic membrane supports the electrolyte, which avoids the undesirable characteristics of liquid electrolytes, and asbestos or ammonia that are substances that have been used to manufacture alkaline electrolyte membranes, which are knowingly toxic and carcinogenic. Aluminum is an inexpensive, abundant element in the earth’s crust and fully recyclable. Oxygen is supplied to the cell with atmospheric air that is pumped through a potassium hydroxide (KOH) aqueous solution in order to fix CO2, and in this way avoid potassium carbonate formation in order to keep the cell fully functional. A sustainable alkaline membrane fuel cell (SAMFC) system with one unitary cell, the reactor, and CO2 purifier was designed and built in the laboratory. The results are presented in polarization and power curves directly measured in the laboratory. Although recycled aluminum was used in the experiments, the results demonstrate that the cell was capable of delivering 0.9 V in open circuit and approximately 0.42 W of maximum power. The main conclusion is that by allowing for in situ sustainable hydrogen production, the SAMFC could eventually become economically competitive with traditional power generation systems.

An underwater superoleophobic nanofibrous cellulosic membrane for oil/water separation with high separation flux and high chemical stability

A nanofibrous cellulosic membrane effectively separates large amounts of oil/water mixtures in chemically harsh environments at high fluxes.

Behavior and biocompatibility of rabbits bone marrow mesenchymal stem cells with bacterial cellulosic membrane

Introduction: Tissue engineering is being redesigned through promising studies that present great potential to create biomaterials capable of forming functional tissues. The cellular expansion and integration depends very much on the quality and adequacy of the surface of the scaffold being determinant for the success in the biological implants. The objective of this research was to characterize and evaluate in vitro the behavior of rabbits Bone Marrow Mesenchymal Stem Cells (BMMSC) when associated with Bacterial Cellulose Membrane (BCM) verifying the adhesion, expansion, cells integration into the biomaterial and the capacity macrophage activation as well as the evaluation of the bacterial cellulosic membrane cytotoxicity and toxicity. Materials and methods: Samples of rabbit bone marrow and mesenchymal stem cells were collected and mesenchymal stem cells were isolated from the medullary aspirates for fibroblast colony forming unit (CFU-F) assays, osteogenic and chondrogenic cellular differentiation induction, cellular integration study to the bacterial cellulosic membrane by Scanning Electron Microscopy (SEM) in the time interval of 1, 7 and 14 days as well as cytotoxicity (NO induction), BCM toxicity (MTT) and phagocytic activity. Results: The CFC-F assay showed cells with fibroblastoid morphology organized in colonies distributed across the culture area surface. In the growth curve two phases (lag and log) were observed in the course of 15 days. The cells multipotentiality was evident after osteogenic and chondrogenic lineages induction. Regarding the BMMSC bioelectrical integration to BCM, in the first 24 hours, the BMMSC were anchored in the BCM. On the seventh day of culture the cytoplasm was scattered and on fourteenth day the cells were fully integrated into the biomaterial. In the phagocytic activity assay there was a significant macrophages activation and for the nitric oxide concentrations and MTT analysis no cytotoxic biomaterial was observed. Conclusion: The bacterial cellulosic membrane allowed the bone marrow progenitor cells expansion and biointegration with stable cytotoxic profile thus presenting itself as biomaterial with potential for tissue engineering.

The impact of MOF feasibility to improve the desalination performance and antifouling properties of FO membranes

In this study, a hydrophilic metal–organic framework (MOF) was applied to improve the performance of a cellulosic membrane for forward osmosis (FO) desalination application.

An unprecedented bacterial cellulosic material for defluoridation of water

Defluoridation of water using bacterial cellulosic membrane.