Biocomposites reinforced with natural fibers: 2000–2010

The kinetics and mechanism of methylene blue adsorption onto raw pine cone biomass (Pinus radiata) was investigated under various physicochemical parameters. The extent of the methylene blue dye adsorption increased with increases in initial dye concentration, contact time and solution pH but decreases with the amount of adsorbent, salt concentration and temperature of the system. Overall the kinetic studies showed that the methylene blue adsorption process followed pseudo-second-order kinetics among various kinetic models tested. The different kinetic parameters including rate constant, half-adsorption time and diffusion coefficient are determined at different physicochemical conditions. Equilibrium data were best represented by Langmuir isotherm among Langmuir and Freundlich adsorption isotherm. The maximum monolayer adsorption capacity of pine cone biomass was 109.89 mg/g at 30°C. The value of separation factor, R
 L, from Langmuir equation and Freundlich constant, n, both give an indication of favourable adsorption. Thermodynamic parameters such as standard Gibbs free energy (∆G
 0), standard enthalpy (∆H
 0), standard entropy (∆S
 0) and the activation energy (A) were calculated. A single-stage batch absorber design for the methylene blue adsorption onto pine cone biomass has been presented based on the Langmuir isotherm model equation.

Equilibrium, Kinetics and Mechanism of Removal of Methylene Blue from Aqueous Solution by Adsorption onto Pine Cone Biomass of Pinus radiata

Present paper involved the review of fixed-bed column studies for removal of various contaminants from synthetic wastewater. Basic concept of adsorption, its types (i.e., chemisorption and physisorption) and its mechanism, adsorbents and adsorbates were included. Comparison of batch and column adsorption study is mentioned. Complete study of breakthrough curve for designing adsorptive column is interpreted. This paper explicates the detailed explanation of various process parameters and isotherm models for column study. Fixed-bed adsorption studies using various adsorbates, i.e., metal, ion, dye and other hazardous materials, are reviewed, in which adsorption of chromium metal is most exploitable. Conclusion and some challenges for utilization in real world are also exposed.

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Fixed-bed column adsorption study: a comprehensive review

Intensive research efforts have been pursued to remove arsenic (As) contamination from water with an intention to provide potable water to millions of people living in different countries. Recent studies have revealed that iron-based adsorbents, which are non-toxic, low cost, and easily accessible in large quantities, offer promising results for arsenic removal from water. This review is focused on the removal of arsenic from water using iron-based materials such as iron-based nanoparticles, iron-based layered double hydroxides (LDHs), zero-valent iron (ZVI), iron-doped activated carbon, iron-doped polymer/biomass materials, iron-doped inorganic minerals, and iron-containing combined metal oxides. This review also discusses readily available low-cost adsorbents such as natural cellulose materials, bio-wastes, and soils enriched with iron. Details on mathematical models dealing with adsorption, including thermodynamics, kinetics, and mass transfer process, are also discussed. For elucidating the adsorption mechanisms of specific adsorption of arsenic on the iron-based adsorbent, X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS) are frequently used. Overall, iron-based adsorbents offer significant potential towards developing adsorbents for arsenic removal from water.

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A critical review on arsenic removal from water using iron-based adsorbents

Banana (Musaceae) is one of the world’s most important fruit crops that is widely cultivated in tropical countries for its valuable applications in food industry. Its enormous by-products are an excellent source of highly valuable raw materials for other industries by recycling agricultural waste. This prevents an ultimate loss of huge amount of untapped biomass and environmental issues. This review discusses extensively the breakthrough in the utilization of banana by-products such as peels, leaves, pseudostem, stalk and inflorescence in various food and non-food applications serving as thickening agent, coloring and flavor, alternative source for macro and micronutrients, nutraceuticals, livestock feed, natural fibers, and sources of natural bioactive compounds and bio-fertilizers. Future prospects and challenges are the important key factors discussed in association to the sustainability and feasibility of utilizing these by-products. It is important that all available by-products be turned into highly commercial outputs in order to sustain this renewable resource and provide additional income to small scale farming industries without compromising its quality and safety in competing with other commercial products.

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Banana by-products: an under-utilized renewable food biomass with great potential.

Free radical-scavenging activity of organic extracts and of pure flavonoids of Blumea balsamifera DC leaves

Oil spill leaves detrimental effects to environment, living organisms, and economy As such, it is of considerable interest to find an effective, simple, and inexpensive method to treat this calamity This work reports the use of banana trunk fibers (BTF) modified with oleic acid, stearic acid, castor oil, and palm oil for oil spill recovery The maximum sorption capacity, effect of oil to water ratio, effect of light oil fractions, and effect of dissolved organic compounds in weathered oil-contaminated seawater were studied It is found that BTF treated with oleic acid exhibited the best sorption capacity for engine oil, dissolved organic compounds in weathered oil, and light oil fractions The equilibrium process was described well by the Freundlich isotherm model, and the kinetic studies show good correlation coefficients for a pseudo-second-order kinetic model

Adsorption kinetics and capacity of fatty acid-modified banana trunk fibers for oil in water.

Problem statement: The aim of this study was to investigate the removal of methyl red, a mutagenic monoazo dye, from various aqueous solutions using banana pseudostem fibers of the size 212-350 micron. Approach: The parameters studied were the effect of pH, amount of adsorbent, contact time, concentration of adsorbate and agitation speed. Results: Equilibrium data were fitted to the Langmuir and Freundlich isotherm models. The data were best represented by the latter with an adsorption capacity and adsorption intensity of 0.351 and 0.302, respectively. Conclusion/Recommendations: Specific rate constants of the processes were calculated by kinetic measurements and a pseudo second order adsorption kinetics was obtained for all cases.

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The Removal of Methyl Red from Aqueous Solutions Using Banana Pseudostem Fibers

Application of biopolymer composites in arsenic removal from aqueous medium: A review

Poly methyl methacrylate (PMMA) is a widely used polymer with various applications. Fourier transform infrared and Raman spectra of PMMA were recorded in range of 4000 – 400 cm-1 and 4000 – 100 cm-1, respectively. In the present investigation, detailed assignments of the observed fundamental bands of PMMA have been analyzed in terms of peak positions and relative intensities. With hope of providing more and effective information on the fundamental vibrations, a normal coordinate analysis has also been performed on PMMA by assuming Cs symmetry. The simple general valence force field (SGVFF) has been employed in normal coordinate analysis and the potential energy distribution (PED) has been calculated for each fundamental vibration. The PED contribution corresponding to each of the observed frequencies shows the reliability and accuracy of spectral analysis.

Mas Rosemal Hakim Mas Haris

Papers

Free radical-scavenging activity of organic extracts and of pure flavonoids of Blumea balsamifera DC leaves

Adsorption kinetics and capacity of fatty acid-modified banana trunk fibers for oil in water.

The Removal of Methyl Red from Aqueous Solutions Using Banana Pseudostem Fibers

Application of biopolymer composites in arsenic removal from aqueous medium: A review

FT-IR and FT-Raman Spectra and Normal Coordinate Analysis of Poly methyl methacrylate