Ba Le Huy

Oil spills pose a significant environmental threat, necessitating the development of efficient and eco-friendly sorbent materials. In this study, a biodegradable cellulose aerogel was successfully synthesized from rambutan peel (RP) waste and evaluated for its diesel oil adsorption performance. The aerogel exhibited ultra-low density (0.027 ± 0.002 g/cm³), high porosity (97.88% ± 0.19%), and excellent hydrophobicity (152.7°). Adsorption experiments demonstrated a maximum diesel oil uptake capacity of 58.8235 g/g under optimal conditions: pH 7, oil concentration of 25 g/L, contact time of 25 s, salinity range of 0‰–35‰, and temperature range of 25–35 ℃. Adsorption equilibrium data were best described by the Langmuir isotherm model (R² = 0.9974), indicating monolayer adsorption with R_L values ranging from 0.0409 to 0.2301 at 25 ℃. Kinetic studies revealed that the pseudo-second-order model provided the best fit (R² = 0.9998), suggesting that adsorption occurred through both boundary layer diffusion and intraparticle diffusion mechanisms. Thermodynamic analysis confirmed the spontaneity and exothermic nature of the adsorption process. Furthermore, the adsorption mechanism was primarily governed by hydrophobic interactions, van der Waals forces, and hydrogen bonding. Overall, this study highlights the potential of cellulose aerogels derived from agricultural waste as sustainable and highly efficient sorbents for diesel oil removal, offering a promising solution for oil spill remediation in various aquatic environments.

Experimental optimization to enhance oil removal efficiency from water using carbonized rambutan peel

This study aims to evaluate the effects of natural and human conditions on vegetation covers using VCI and TCI indices (the satellite-based Vegetation Health Indices (VHIs)) in Dak Nong province. Factors affecting the VHIs included in the analysis involve land use, soil, population, topography, distance to roads and surface water. The data analysis period is the dry season from 2000 to 2020. The trend of the VHIs’ change in this study is analyzed using Sen’s method with monitoring data from Modis. The effects of factors affecting the VHIs are based on logistic regression and discriminant analysis. The analysis results show that the VHIs are clear and show both increasing and decreasing trends. Based on logistic regression analysis, the influence of land use types on the trend of the VHIs in the direction of increasing from negative to positive will be from PdF, UnL, AnC, SpF, PtF, PeA and then to PdR. Corresponding to the soil will be from ACa, FRp, FRx, FRr, ACh, LVx, FLg and then to LVg. Based on the discriminant analysis method, it was found that there are only four primary factors affecting the trend of the VHIs in order of decreasing level of closure: population density, land use, soil and population growth rate and to the road. These results show that in places where labour resources are available, plants are interested in investment due to high profits, nutrient-rich soil and convenience for plant care; the VHIs tend to increase and vice versa. Compared with VCI, the trend of TCI tends to be sloping negative and more pessimistic. Through the coefficients of the logistic regression equation and the difference function, the TCI is more sensitive than the VCI when the independent variables change, especially for changes in population density and land use. Thus, TCI can be considered the preferred option for assessing vegetation health trends in the context of climate change.

This book covers all areas of environment, geography and earth science. The contributions by the authors include numerical simulation; air flow; lower and middle atmosphere; photo-voltaic; desalination; reverse osmosis; phytoattenuation; heavy metals; vetiver (Vetiveria zizaniodides); sunflower; biostimulator; Gibberellic Acid (GA3); Indol-3-Acetic Acid (IAA); dissolved oxygen; microbiological parameters; untreated liquid waste; water quality indicators; formaldehyde; health risk; exposure model; clothing; Vietnamese consumers; Yenisei River; Elodea Canadensis; americium-241; toxicity; Loei-Wang Saphung (LWS); gypsum-anhydrite deposits; diagenesis; recrystallization; rehydration; heavy metals; chemisorption; biochar; fishbone; molecular sieves; bioremediation; precipitation; Meghadrigedda; GIS and remote sensing; erosion; siltation of the reservoir; bio-indicator; contaminants; diversity index; nematodes; soil; environment; population, municipal corporations; water bodies; sewage treatment plants; encroachments; wetland ecosystem etc. This book contains various materials suitable for students, researchers and academicians in the field of environment, geography and earth science.