2023-03-23 チャルマース工科大学
◆チャルマース工科大学の研究グループは、セルロースナノ結晶を利用することで水質浄化を行う方法を開発した。彼らは、アジアの発展途上国で問題となる染料汚染水の処理に適用することを目的としている。
◆研究者らは、セルロースナノ結晶を利用した生分解性の高い材料を開発し、紫外線を使って染料を分解することで水質を浄化する。処理に圧力や熱は必要なく、太陽光を利用して効率的に染料を除去できるため、費用対効果が高く、設置や使用も簡単である。
◆この技術は、インドの繊維産業の汚染問題を解決するために、地方の産業で実際に試験される予定である。また、この材料は、染料以外の他の種類の汚染物質の処理にも使用できる可能性がある。
＜関連情報＞
- https://news.cision.com/chalmers/r/new-wood-based-technology-removes-80-percent-of-dye-pollutants-in-wastewater,c3739225
- https://pubs.acs.org/doi/10.1021/acs.iecr.2c03365
- https://www.sciencedirect.com/science/article/abs/pii/S0045653521027594?via%3Dihub
微結晶セルロースから誘導されたセルロースナノ結晶によるヤヌスグリーンアゾ染料の選択的除去法 Cellulose Nanocrystals Derived from Microcrystalline Cellulose for Selective Removal of Janus Green Azo Dye
Ruchi Aggarwal, Anjali Kumari Garg, Deepika Saini, Sumit Kumar Sonkar, Amit Kumar Sonker and Gunnar Westman
Industrial & Engineering Chemistry Research Published:December 26, 2022
DOI:https://doi.org/10.1021/acs.iecr.2c03365
Abstract
Cellulose nanocrystals (CNCs) as a bio-based adsorbent material have been synthesized at mild temperature reaction conditions using acid hydrolysis of microcrystalline cellulose (MCC) by sulfuric acid. CNCs by a simple acid treatment become enriched with negatively charged surface functionalities and shows good adsorption capacity. The CNCs have been characterized by X-ray photoelectron spectroscopy, Fourier transform Infrared, X-ray diffraction spectroscopy, and thermogravimetric analysis for their chemical composition, functionality, crystallinity, and stability, respectively. Sulfated CNCs have been used to selectively remove the toxic Janus Green (JG) dye tested out of many other dyes via adsorption and showed a Langmuir adsorption capacity of ∼77 mg g. –1 The effects of pH, temperature, concentration, and loading capacity have also been explored. The adsorption kinetics follows the pseudo-second-order pathway and thermodynamic analysis of the system indicates that the process is exothermic and spontaneous. Moreover, for the practical applicability of the proposed method, the adsorption of JG was also analyzed in four spiked industrial samples collected from nearby textile industries, where they removed more than 80% of the dye from the complex industrial water system.
セルロース由来光活性炭素ドットによる有害な六価クロムの太陽光による除去 Sunlight promoted removal of toxic hexavalent chromium by cellulose derived photoactive carbon dots
Ruchi Aggarwal, Deepika Saini, Sumit Kumar Sonkar, Amit Kumar Sonker, Gunnar Westman
Chemosphere Available online: 17 September 2021
DOI:https://doi.org/10.1016/j.chemosphere.2021.132287
Abstract
A scalable synthetic procedure for fabricating photoactive carbon dots (CD) from microcrystalline cellulose (MCC) is presented. The MCC was transformed into a photoactive nanosized CD by a one-step acid-assisted thermal-carbonization (~90 °C for 30 min). The efficiency of the obtained CD was determined by photo-removal of toxic hexavalent chromium (Cr(VI)) ions from wastewater. CD obtained from cellulose completely removed 20 ppm of Cr(VI) wastewater within ∼120 min under sunlight illumination. No Cr(VI) removal was observed in dark conditions and with control cellulose material as reference samples. The Cr(VI) removal follows pseudo-first-order kinetics along with a half-life of ∼26 min. Furthermore, the Cr(VI) removal from wastewater was supported via cyclic voltammetry analysis. Using a low-cost, naturally available cellulose material and sulfuric acid, the world’s most-used chemical, creates techno-economic prerequisites for a scalable process of photoactive carbon dots.
