07/02/2023 3:00 PM GMT+7 TP HCM
Separation and Purification Technology 304 (2023) 122415
Authors: Luon Nguyen Tan a,b, Nhung Cam Thi Nguyen a,b, Anh Mai Hoang Trinh a,b, Nga H.N. Do a,b, Kien A. Le c, Phung K. Le a,b,*
a Refinery and Petrochemical Technology Research Centre, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Viet Nam
b Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Viet Nam
c Institute for Tropicalization and Environment, 57A Truong Quoc Dung Street, Phu Nhuan District, Ho Chi Minh City, Viet Nam
Accepted 14 October 2022
Available online 19 October 2022
Abstract. Chromium (VI) oxyanion is one of the most toxic contaminants in water which causes cancer and genetic mutations in humans. In this work, the bio-based aerogels are successfully synthesized from pineapple leaves (PLs) and chitosan (CS) by an effective and eco-friendly method (including homogenizing, mixing, and freeze-drying) that is feasible for mass production to manage Cr(VI) pollution.
The influences of different freezing approaches (refrigerator, isotropic and anisotropic freezing), solid concentrations, and weight ratios of cellulose to chitosan on the morphology, physical parameters, and Cr(VI) adsorption of the aerogels are comprehensively investigated. The fabricated aerogels are ultra-lightweight (20–30 mg/cm3), highly porous (above 97.5%), durable (Young’s modulus of 1.8–11.7 kPa), and strongly acid resistant (below 12% of weight loss at pH 3).
The difference in pore size among freezing techniques is clarified by scanning electron microscopy, suggesting that anisotropic freezing is ineffective for non-nanoprecursors. The findings show the strong influence of chitosan content and pH of the medium on Cr(VI) adsorption of the PL/CS aerogels due to the electrostatic attraction between Cr(VI) oxyanions and protonated amine groups.
The theoretical Langmuir maximum Cr(VI) uptake is up to 210.6–211.4 mg/g, which is generally comparable to carbon-based and costly metal-organic framework materials.
The adsorption isotherm and kinetics of the samples are appropriate to the Langmuir model and the pseudo-second-order model, respectively. Furthermore, the Cr-absorption capacity retention rates of prepared aerogel are above 75% after 6 absorbing cycles by NaOH solution. Based on the results, the product cellulose/chitosan aerogel can be considered a potential adsorbent for Cr(VI) removal.
On 22/10/2015, CARE has organized the meeting of the Scientific Council with the chairmanship of Dr. Nicolas Gratiot - Director and Chairman of the Scientific Council, Assoc. Pro. Vo Le Phu (on behalf of Assoc. Pro. Nguyen Phuoc Dan - Deputy Chairman)
Project description The availability of High Resolution Imagery (spatial, spectral, and radiometric) with an increased time revisit (Landsat-8 and now Sentinel-2) opens the way to a more detailed observation of coastal zones and inland waters (large rivers, lakes and reservoirs)
On 08 September 2016, the delegation from Institute of Research for Development (IRD – France) led by Mr. Thierry Lebel - Director of the Promotion of Interdisciplinary and Intersectoriality and Mr. Frédéric Ménard
The pretty work, a monography collection of 15 megacities in the world about "Water, megacities and Global Change”, has been published by UNESCO. The CARE Lab-HCMUT Researchers are honored to represent Ho Chi Minh City by contributing an article
CARE Lab-HCMUT is pleased to present you our publication of the monography "Ho Chi Minh City growing with water-related challenges".
CARE Lab-HCMUT and PADDI, a member of the Ho Chi Minh City delegation, participated in the 26th Environment exhibition POLLUTEC, Lyon (France), which took place from 30/11 to 02/12/2016.
Tuteur: Dr. BUI Xuan ThanhAssociate Professor in Environmental Engineering,Head, Department of Water Science & Technology Faculty of Environment & Natural Resources