Ewa Szefer^*, Agnieszka Leszczyńska, Edyta Hebda, Krzysztof Pielichowski

Journal of Renewable Materials, Vol.9, No.6, pp. 1127-1142, 2021, DOI:10.32604/jrm.2021.014584 - 11 March 2021

Abstract The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement. A series of all-bionanocomposites containing unmodified and surface modified cellulose nanocrystals with CNC content in the range of 1–3 %_w.t. were obtained by melt blending and tested by XRD, SEM, DSC and DMA to investigate the effect of surface esterification of CNCs on the structure, morphology, dynamic mechanical properties of bionanocomposites, as well as phase transitions of PLA in the presence of cellulosic nanofiller. More > Graphic Abstract

Jiangbo Li^1,2, Lielin Wang^1,2,*, Hua Xie^1,2, Xiaoyu Li^1,2, Zhiqiang Feng^1,2, Wenxiu Zhang^1,2

Energy Engineering, Vol.117, No.3, pp. 129-142, 2020, DOI:10.32604/EE.2020.010336 - 10 July 2020

Abstract This study introduced a significantly effective approach called the microwave-enhanced Fenton method to degrade spent radioactive cation exchange resin. Compared with the Fenton (99% after 180 min) and photo-Fenton (90% after 198 min) reactions, this unique microwave-enhanced Fenton reaction has the highest degradation rate for spent radioactive cation exchange resin degradation (98.55% after 60 min). Carbon dioxide, sulfate and small molecular compounds were produced in the degradation of cation exchange resin, as determined by XRD and FT-IR. A model for the microwave-enhanced Fenton degradation mechanism of cation exchange resin was constructed. Microwaves were implemented to More >

Nadezhda Petkova^1,*, Radka Arabadzhieva¹, Dragomir Vassilev², Gergana Gencheva¹, Yulian Tumbarski³, Tsveteslava Ignatova-Ivanova⁴, Sevginar Ibryamova⁴, Mina Todorova¹, Milena Koleva², Panteley Denev¹

Journal of Renewable Materials, Vol.8, No.4, pp. 365-381, 2020, DOI:10.32604/jrm.2020.09292 - 24 April 2020

Abstract Microwave-assisted irradiation was performed for esterification of chicory inulin with high degree of polymerization with acetic anhydride without a solvent only with a catalyst. The resulting esters were characterized by melting point, hydrophilic-lipophilic balance, thin-layer chromatography, ultraviolet spectroscopy, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. Inulin acetate demonstrated a high degree of acetylation (2.5–3.0) and presented a white, water-insoluble substance with bitter taste. The FTIR and NMR spectra confirmed esterification and demonstrated the incorporation of hydrophobic residue to the water soluble inulin backbone. Swelling capacity, water holding, oil-holding capacities, the foamability,… More >

Nadezhda Petkova^1,*, Gergana Gencheva¹, Dragomir Vassilev², Milena Koleva², Albert Krastanov³, Panteley Denev¹

Journal of Renewable Materials, Vol.6, No.7, pp. 671-679, 2018, DOI:10.32604/JRM.2018.00001

Abstract Jerusalem artichoke (Helianthus tuberosus L.) tubers are industrial crop considered as a promising source for inulin production. “Green” method was performed for accelerated inulin extraction from Helianthus tuberosus L. tubers by the application of microwave irradiation. Further pretreatment of the water extract with acetone and ethanol yielded inulin (20%) with purity 89% and degree of polymerization 18. Jerusalem artichoke inulin was characterized by FTIR and NMR spectroscopy. For the first time eco-friendly synthesis of acetylated Jerusalem artichoke inulin was performed by the reaction with acetic anhydride, without toxic solvent, but only with sodium acetate as More >