RESUMO
ZSM-5 zeolite was successfully synthesized from bentonite clay sourced from Lam Dong Province, Vietnam, using the hydrothermal method at 170 °C for 18 h. The synthesized ZSM-5 (SiO2/Al2O3 ratio ~ 34) exhibited a single phase with high crystallinity (91.8%), and a clear and uniform shape. In a detailed examination of the synthesized material's Pb(II) adsorptive capacity, various factors were taken into account, including pH, interaction time, ionic strength, and the amount of adsorbent. Isotherms and kinetics were examined to elucidate the uptake behavior. Study results suggested that Pb(II) ion uptake by ZSM-5 was most appropriately described by the Sips isotherm and intraparticle diffusion kinetic models. The calculated maximum monolayer adsorption capacity according to the Langmuir isotherm model was 48.36 mg/g. Furthermore, the adsorption mechanisms of Pb(II) on ZSM-5 involving electrostatic interactions, ion exchange, and diffusion into pores were demonstrated using the analytical techniques before and after Pb(II) adsorption. These findings demonstrate that ZSM-5 synthesized from bentonite clay exhibits an excellent adsorption capacity for Pb(II), resulting in promising applications for treating drinking water or aqueous industrial waste containing Pb(II) ions.
Assuntos
Bentonita , Argila , Poluentes Químicos da Água , Adsorção , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Cinética , Chumbo , Dióxido de Silício , População do Sudeste Asiático , Vietnã , Água , Poluentes Químicos da Água/análiseRESUMO
Kinetic studies play an instrumental role in determining the most appropriate reaction rate model for industrial-scale applications. This study focuses on the kinetics of methylene blue (MB) adsorption from aqueous solutions by biochar derived from jackfruit peel. Various kinetic models, including pseudo-first-order (PFO), pseudo-second-order (PSO), intra-diffusion, and Elovich models, were applied to study MB adsorption kinetics of jackfruit peel biochar. The experiments were performed with two initial concentrations of MB (24.23 mg/L and 41.42 mg/L) over a span of 240 min. Our findings emphasized that the Elovich model provided the best fit of the experimental data for MB adsorption. When compared to other materials, biochar from jackfruit peel emerges as an eco-friendly adsorbent for dye decolorization, with potential applications in the treatment of environmental pollution.
Assuntos
Artocarpus , Poluentes Químicos da Água , Azul de Metileno , Cinética , Concentração de Íons de Hidrogênio , Monitoramento Ambiental , Água , AdsorçãoRESUMO
This study develops a model to raise public awareness about the consequences of burning rice straw after harvest, including environmental pollution, soil degradation, and increased CO2 emissions that contribute to the greenhouse effect. The distinctive feature of the research is the introduction of a post-harvest rice straw treatment process using microbial products capable of secreting cellulase enzymes, which can break down the cellulose in the straw. This process shortens the decomposition time and produces natural organic fertilizer, thus reducing cultivation costs by 60% and increasing crop yields by 20%. The experimental model was carried out in Cam My district, Dong Nai province, Vietnam, including 4 models: no microbial products; using Bio Decomposer; using NTT-01; and using NTT-02. Each experimental field had an area of 650 m². The results showed a significant reduction in straw decomposition time after 14 days of use of the products, with a decomposition rate of up to 80%, nearly twice as fast as without the products. This helps save time, produce natural organic fertilizers, reduce care costs, and increase rice yields, resulting in more income for local residents. These findings demonstrate the effectiveness of microbial treatments in sustainable agriculture and their potential for a broader application in the management of agricultural waste.