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Our current industrial ammonia cycle is far from being sustainable – while intense energy is required to produce ammonia – almost half of it ends up in wastewater treatment plants (WWTPs) where is finally transformed and lost. This work shows the application of flat sheet membrane distillation (MD) commercial modules for the ammonia recovery from WWTPs. First, optimized operating conditions – in terms of ammonia flux, specific thermal energy (STEC) and chemical demand – were investigated in the laboratory with a 2.3 m2 MD module. Second, optimized conditions were demonstrated in a pilot installation on site operating a 14.5 m2 MD module continuously (24/7) for three months. Results showed that MD is a robust, low-maintenance technology that can be operated at low temperature and corresponding STEC (i.e. 38 °C and 13.6 kWhth per kg1 NH3, respectively) and low pH (i.e. 8.7) for the recovery of 90% of the water-bound ammonia as an ammonium sulphate (AS) solution. The AS product reached a concentration of 5 g l-1 N–NH4, lower than conventional fertilizers, however given its high quality and volume reduction factor, it constitutes a potential fertilizer solution for local needs. The maximum AS permeate concentration was limited by the increasing water vapour flux due to a higher osmotic distillation effect and a minor ammonia flux decrease with increasing permeate concentration. Further research will focus on optimizing the module configuration to minimize water flux and overall system operation for increased heat recovery and open-loop operation.

Biomimetic systems represent one of the most attractive ways to produce artificial complex devices taking the best from nature in a simple and repetitive manner. Some of these systems can imitate trees in some of their functions, in this article, the objective is to imitate trees in their ability to fixate CO 2 and use it to produce organic compounds. As trees do that fixation after the penetration of the gas though the smart pores of the leaves, stomata, we call our pores as artificial stomata. The project aims to end up with compact systems for small size devices that would work with autonomy in the near future in energy systems. Polysulfone based membranes were prepared by a Phase Inversion Precipitation method using different polymeric solutions (N,N-Dimethylformamide or 1-Methyl-2-pyrrolidone). Obtained asymmetric fingerlike, droplike, or spongy morphologies were characterized: by SEM and ESEM equipped with EDX, while their surfaces were investigated by: AFM, dynamic and static contact angle, swelling measurement. Moreover, copper - ferrite nanoparticles, used for preparation of composite membranes was characterized by TEM, and X-ray diffraction. Their influence on material CO 2 solubility, membrane surface morphology and wettability were deeply investigated, and demonstrated influence of membranes roughness on their performance. Furthermore, generated results reveled higher CO 2 assimilation than the natural stomata and shown very high CO 2 absorption flux (67.5 mmol/m 2 *s).

The growing interest of oncologists in natural compounds such as polyphenols and flavonoids is encouraging the development of innovative and efficient carriers for the delivery of those drugs. This study examines carboxymethyl chitosan-based microcapsules created by spray drying as a method for delivering biologically active compounds isolated from the Cistus herb. Effects of sterilization and encapsulation on the polyphenol and flavonoid content of Cistus extract were investigated to optimize the production process. Furthermore, in vitro studies were carried out to examine the anticancer properties of sterilized polyphenols and flavonoids on glioblastoma cells isolated from oncological patients. Acquired results show high anticancer potential towards glioblastoma as well as low cytotoxicity towards non-cancer cell lines by the substances in question. Steam sterilization is shown to affect the content of biologically active compounds the least. We demonstrate that the investigated form of drug encapsulation is both efficient and potentially possible to scale up from the viewpoint of the pharmaceutical industry.

In this study we explored the implementation of the vapor induced phase separation (VIPS) to produce cellulose acetate microcapsules for the encapsulation of a complex mix of fragrances. VIPS is a technique used for membrane preparation, but barely mentioned for microencapsulation. We compared the products from VIPS and a more common microencapsulation process, the immersion precipitation technique (IPS). The capsules prepared via VIPS show a core-shell structure with a thin polymeric shell surrounding the internally empty space, conversely to those produced via IPS, showing an incomplete spherical morphology. This can be attributed to a better control of the precipitation rate of the encapsulation material in the non-solvent thanks to the longer exposition time to the vapor. The activity and encapsulation efficiency of the capsules, obtained through TGA analysis, reached a maximum of &asymp, 75% and &asymp, 90%, respectively. Moreover, a growing trend between the initial active concentration and the encapsulation efficiency is noticed.

Constant increase of greenhouse gas emission by human activity causes a climate change, with carbon dioxide as the main contributor. In nature, CO2 fixation takes place in leaves where carbonic anhydrase (CA) catalyzes the hydration reaction. Inspired by this photosynthesis process, we come with a polysulfone biomimetic membrane containing CA for CO2 capture. Two immobilization approaches were investigated: physical and chemical. For this reason, we prepared a blank polysulfone membrane to physically adsorb the enzyme on its surface, and a membrane with dispersed ferritic nanoparticles -NH2 terminated used for covalent binding of the enzyme. The scope of this study is to evaluate the influence of the immobilization type on the enzyme activity. The obtained nanoparticles and membranes were characterized by TEM, WAXD, EDX, SEM and CA, respectively. The attached amount was determined by ICP, whereas the activity and CO2 solubility were estimated experimentally. Studies showed that the enzyme is attached more efficiently by the physical adsorption. Nevertheless, covalent binding favors its activity by stabilizing the structure.