Search results for "ligniini"
showing 5 items of 25 documents
Encapsulation of AgNPs in a Lignin Isocyanate Film : Characterization and Antimicrobial Properties
2023
Lignin isolated from agricultural residues is a promising alternative for petroleum-based polymers as feedstocks in development of antimicrobial materials. A polymer blend based on silver nanoparticles and lignin–toluene diisocyanate film (AgNPs–Lg–TDIs) was generated from organosolv lignin and silver nanoparticles (AgNPs). Lignin was isolated from Parthenium hysterophorus using acidified methanol and used to synthesize lignin capped silver nanoparticles. Lignin–toluene diisocyanate film (Lg–TDI) was prepared by treating lignin (Lg) with toluene diisocyanate (TDI) followed by solvent casting to form films. Functional groups present and thermal properties of the films were evaluated using Fo…
Characterization of lignin enforced tannin/furanic foams
2020
Worldwide, tons of lignin is produced annually in pulping plants and it is mainly considered as a waste material. Usually lignin is burned to produce energy for the pulping reactors. The production of value-added materials from renewable materials like lignin, has proved to be challenging. In this study, the effects of addition of three different types of lignin in the production of tannin/furanic foams is investigated. The foams were matured, first at 373 K and finally carbonized at 1073 K and the properties of them including mechanical strength, specific surface area and pore development are investigated before and after thermal treatment. According to the results, higher mechanical stren…
Value-added bioproducts or renewable energy derived from lignin? : comparative regional economic and environmental impact assessment : case Metsä Gro…
2016
Metsä Group’s next-generation bioproduct mill in Äänekoski will be operational within Q3/2017 and it will have significant regional economic impact on Central Finland. The mill will operate applying principles of circular economy, and thus utilize all possible side streams from pulp production. Lignin is one of the side streams that has huge potential to be refined, as sustainable products and by creating new value added. Conventionally, lignin is combusted with black liquor to generate energy in pulp mills. This thesis compares this conventional situation to refining lignin into biocomposite products made from 100% renewable resources with regard to regional economic and environmental impa…
Tyypillisten biomassamateriaalien kemiallinen koostumus
2009
Temporal perspective of humification of organic matter
2004
Humustumisprosessissa kuollut orgaaninen aines hajoaa maaperässä. Osa tästä orgaanisesta aineesta mineralisoituu hiilidioksidiksi ja vedeksi lopun jäädessä maaperään ja muodostaa humusaineita, joita ovat humushappo, fulvohappo ja humiini. Humusaineilla, erityisesti humushappojakeella, on myönteisiä vaikutuksia maaperään sekä kasvien kasvuun. Huolimatta yli 200 vuoden tutkimuksista yksiselitteistä teoriaa humushappojen kemiallisesta rakenteesta tai niiden synteesistä ei vielä ole esitetty. Osa teorioista painottaa humushappojen rakenteen keskeisinä tekijöinä ligniiniä ja aromaattisuutta, osa teorioista taas korostaa hiilihydraattien ja alifaattisuuden merkitystä.Koivulan tutkimuksessa ns. hi…