Jeyashelly Andas

Optimization of preparation conditions for activated carbon from banana pseudo-stem using response surface methodology on removal of color and COD from landfill leachate

This study determined the optimum conditions for preparation and adsorptive treatment of landfill leachate from banana pseudo-stem based activated carbon. Response surface methodology (RSM) based on Box-Behnken was applied to optimize the combination effect of three important reaction variables, i.e. activation temperature (°C), activation time and impregnation ratio (IR). The reaction was performed via a single step activation with ZnCl2 in a closed activation system. A series of 17 individual experiments were conducted and the results showed that the RSM based on BBD is very applicable for adsorptive removal of pollutants from landfill leachate treatment. The optimum conditions obtained by Design of Experiments (DOE) was at 761°C activation temperature, 87min activation time and 4.5g/g impregnation ratio with product yield (27%), iodine number (1101mg/g), color removal (91.2%) and COD removal (83.0%).

Review on Applications of Nanoparticles in Landfill Leachate Treatment

Sanitary landfill is the most common way to eliminate solid waste. However, sanitary landfill generates large quantity of leachate. Leachate can be defined as a liquid that passes through a landfill and extracted dissolved and suspended matter. The presence of large quantity of contaminants in leachate is harmful to human and ecological environment. This can lead to health issues, including gastrointestinal illness, reproductive problems, and neurological disorders. There are several significant techniques have been made to overcome the problem of leachate pollution, including photocatalytic oxidation, adsorption/separation processing and bioremediation. However, the applications have been restricted by many factors, such as processing efficiency, operational method, energy requirements, and economic benefit. This present article provides an overview of research studies and advances concerned with the development of nanoparticles and their potential applications in leachate treatment. Nanoparticles can act as antimicrobial and function as reducing agent and catalyst in detoxification of pollutants in the environment, such as organic, inorganic and heavy metals. NPs have been suggested as efficient, cost-effective and environmental friendly alternative to existing treatment materials and presents a number of potential environmental benefits.

Adsorptive removal of dissolved organic matter (DOM) in landfill leachate by iron oxide nanoparticles (FeONPs)

A study was conducted to investigate the efficiency of iron oxide nanoparticle (FeONPs) adsorption for removing of DOM in landfill leachate. FeONPs was directly prepared via sodium borohydride (KBH4) reduction method. Adsorption kinetics, isotherm and thermodynamic studies were developed to design the model for DOM removal. Pseudo first-order and pseudo second-order model have been studied to fit the experimental data. The regression results showed that the adsorption kinetics were more accurately represented by a pseudo second-order model. The Weber–Morris intraparticle diffusion model was used to analyze the adsorption kinetics data. The plot of qt versus t1/2 represents multi linearity, which showed that the adsorption processes occurred in more than one step. Adsorption isotherms were analyzed by Langmuir, Freundlich, Tempkin and Dubinin–Radushkevich, isotherms model. Equilibrium data were well fitted to the Dubinin– Radushkevich isotherm model. Maximum monolayer adsorption based on Langmuir was calcu...

Synthesis and Characterization of Biomass Supported Ag, Co and Ag-Co Nanoparticles

Silica extracted from rice husk was used as a support to synthesize the monometallic Ag, Co and bimetallic Ag-Co nanoparticles. The nanoparticles were prepared via a sol-gel method by adding glucose as the reducing agent. The prepared nanoparticles were designated as Ag-NP, Co-NP and AgCo-NP. The successful incorporation of Ag/Co onto the silica surface were evidenced by TEM, FT-IR and DR/UV-Vis analysis. The TEM analysis showed the presence of small spherical shape nanoparticles with an average mean size of 3.18-3.57 nm. Through DR/UV-Vis analysis, the presence of Ag+ and cobalt in the oxidation state of +2 and +3 were confirmed, while FT-IR verified the presence of M-O and Si-O-M+ bond.

Facile Synthesis of Activated Carbon from Swamp Taro Stalk via Single Step ZnCl2 Activation

In this work, mesoporous activated carbon with high surface area was synthesized from swamp taro stalk by single step ZnCl2 activation. The synthesized activated carbon was characterized by Na2S2O3 volumetric method, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM) and N2 adsorption-desorption analyses. Under the single step ZnCl2 activation, the registered iodine number, BET surface area, total pore volume and pore diameter were 1087.57 mgg-1, 1242.26 m2g-1, 0.73cm3g-1 and 3.72 nm respectively with yield of 25.34%. SEM analysis evidenced the well-formation of porous structure. Type IV isotherm with H2 loops obtained from N2-sorption studies indicates the ink bottles shape mesoporous network structure. This research proved the successful conversion of plant waste into high grade activated carbon.

Facile Synthesis and Characterization of Fe-Co Nanoparticles Supported Silica Rice Husk

A series of Fe-Co nanoparticles were synthesized via sol-gel route at acidic, neutral and basic condition using rice husk as the silica source. The synthesized nanomaterials were designated as Fe-Co3, Fe-Co7 and Fe-Co9 and characterized by Fourier Transform Infrared (FTIR), Transmission Electron Microscope (TEM) and particle size analyzer. The great effect of pH was clearly evidenced from the shifting in the siloxane bond in the FTIR spectrum. TEM investigation confirmed the existence of discrete and almost sphere like nanoparticles. The particle size decreased with an increase in the pH, registering the smallest average particle size at pH 9. In brief, this study promises a fast, rapid and promising method for the conversion of silica rice husk into nanoscale bimetallic materials.

Development of activated carbon from banana pseudo-stem via single step of chemical activation

Activated carbon with high surface area was successfully produced from banana pseudo-stem through a single step chemical activation process. The effect of activation parameters such as types of activating chemical (ZnCl2 and H3PO4), impregnation ratios (1:1, 1:2, 1:3, 1:4 and 1:5 precursor/activating agent), activation time (30, 60, 90 and 120 min) and activation temperature (400, 500, 600, 700 and 800 °C) were evaluated based on optimum product yield and iodine number. The optimized parameters were found at impregnation ratio of 1:2 using ZnCl2, activation time and the activation temperature of 60 min and 600 °C respectively. The product obtained from optimum parameters was further investigate using chemical and textural characteristic by using N2 adsorption-desorption measurement, elemental analyser CHNS, SEM, FTIR. The result suggested that the AC possessed of mesoporous structure. BET surface area, total pore volume and pore diameters of the AC prepared from optimum condition were 1329.5 m2/g, 1.16 cm...

Silica Rice Husk Supported Ag/ZnO Nanoparticles for an Improved Visible-Light Photocatalytic of Methylene Blue

Nanostructure ZnO and Ag/ZnO were successfully synthesized from rice husk via an eco-friendly sol-gel method. Structural investigations by FT-IR and DR/UV-Vis analyses confirmed the successful inclusion of metal species into the silica framework. XRD and TEM studies evidenced the well-dispersion of silver and zinc onto the silica support. Modification of ZnO with Ag resulted in the maximum photocatalytic activity (90.5 %) of methylene blue, (40 mgL-1) under compact fluorescent lamp irradiation. Minimal agglomeration, high dispersion and narrow band gap energy of Ag/ZnO was suggested to contribute to its excellent photocatalytic activity in comparison to ZnO.

Structural Investigation of Ceria and Copper Modified Silica from Agricultural Biomass

Monometallic Ce, Cu and bimetallic Ce-Cu was successfully synthesized at room temperature using silica rice husk (RH) via sol-gel route and were characterized through several physicochemical techniques such as N2 adsorption-desorption, XRD and DR/UV-Vis analyses. The prepared materials were designated as RH-10Cu, RH-20Ce and RH-10Cu20Ce. High mesoporosity with Type IV characteristics were evidenced for all the materials. The BET surface area registered for RH-10Cu, RH-20Ce and RH-10Cu20Ce were 396.02, 245.54 and 194.87 m2g-1 respectively. Well-dispersion of metal species was clearly evidenced from XRD analysis. The strong interaction between ceria and copper was observed over RH-10Cu20Ce through DR/UV-Vis analysis.

From Rice Husk into Discreet 0-D Ag/ZnO Nanomaterial

In this work, highly mesoporous Ag/ZnO was rapidly developed from rice husk, a cheap agricultural biomass with urea as the reducing agent at acidic medium. A facile and cheap sol-gel method combined with calcination was employed to produce Ag/ZnO 0-D nanoparticles. TEM investigation revealed the formation of spherical and discreet nanoparticles with an average particle size of 13.55 nm. Ag/ZnO with semi-crystalline nature was confirmed from the high-angle XRD study. A type IV isotherm with high Brunauer–Emmett–Teller surface area of 416.78 m2g-1 was exhibited by Ag/ZnO nanoparticles.