Now showing1 - 2 of 2
- Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Organic bio-based aerogel from food waste : preparation and hydrophobization(Multidisciplinary Digital Publishing Institute (MDPI), 2022-10-26); ; ; ; In this work, organic aerogels from spent ground coffee and apple pomace were prepared and characterized for the first time. Apple aerogel was found to be much lighter than that from coffee (0.19 vs. 0.016 g/cm₃, whereas the specific surface areas are comparable (229 vs. 208 m₂/g). Being intrinsically hydrophilic, these aerogels were silanized, both in liquid and gas phase, to increase stability in aqueous media. The latter modification method allowed chemical grafting of the silane to the aerogel surface (evidenced by FTIR and TGA) and resulted in certain hydrophobicity, as was evidenced via contact angle measurements: both aerogels possess a contact angle of ca. 100° after the gas hydrophobization, while for the pristine aerogels it was 50°. Furthermore, it was observed that the gas-phase silanization process is more applicable to apple aerogels.Publicationtype: Journal ArticleScopus© Citations 5 156 362 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Natural grown aerogels from fruits, vegetables and mushrooms : processing and characterization(2022-09); ; ; ; Aerogels are highly porous materials with special properties like a high specific surface area up to 1200 m2 g-1 and low densities of approx. 0.1 g cm-3. Especially biopolymer aerogels (e.g. alginate, chitosan and cellulose) are used due to their high availability, biocompatibility and non-toxicity. The applications of these mesoporous materials are in fields of carrier matrices (food and pharma), thermal insulation and catalyst scaffolds. Biopolymer aerogel production requires a gelation step, in which the porous network is formed. Gelation is normally carried out in aqueous phase and can be induced via different methods (e.g. change of temperature, pH, addition of ions, etc.), followed by solvent exchange and supercritical drying. Fruits, vegetables, mushrooms and derived plant based food waste show internal three-dimensional pore networks formed by natural growth. Therefore, they can be converted into aerogel-like systems, without requiring a gelation step. The importance of sustainable processes in the (food) industry is growing steadily. In addition to energy efficiency and resource management, this also includes the recycling of food waste and by-products. Hence, the development of an alternative recycling method of food waste to natural grown aerogels is a promising solution to meet the economic requirements. The aim of this work is to provide an overview of different natural grown aerogels, which are produced based on their naturally aqueous state by solvent exchange with ethanol and supercritical drying at suitable conditions (40 °C and 100 bar). Furthermore, the aerogel-like morphology of supercritical dried fruits and vegetables is characterized. For this purpose, experimental investigations are performed related to the specific surface area (BET method), internal mesoporous structure (SEM pictures), density and volumetric shrinkage during the manufacturing process.Publicationtype: Conference Poster not in Proceedings180 123