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Journal of Thermal Analysis and Calorimetry
Authors: Alexandre Prado, Aline Moura, Rômulo Andrade, Igor Pescara, Valéria Ferreira, Elaine Faria, Augusto de Oliveira, Esmeralda Okino, and Luiz Zara

operations such as fly ash, coal, and oxides have been used in order to replace the costly ones in recent years [ 12 – 16 ]. Many byproducts of furniture industries and civil construction as sawdust have little or no economic value, and which have

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the potential for energy recovery. Thermochemical conversion such as pyrolysis could be a viable option for an environmentally acceptable way to manage agricultural biomass waste, such as wood waste or sawdust wood waste (SWW) ( Titiloye et al., 2013

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Abstract  

Application study for the evaluation of sorption characteristics of sawdust as an economical sorbent material used for decontamination of radioisotopes cesium and europium from aqueous solution has been carried out in the present work. In this respect, sawdust (untreated and treated by HNO3) has been prepared from the commercial processing of wood for furniture production. Pore properties of the activated carbon such as BET surface area, pore volume, pore size distribution, and pore diameter were characterized by N2 adsorption and DFT software. Radiotracer method onto sawdust from aqueous solutions was studied in a batch technique with respect to pH, contact time, temperature. The kinetics of adsorption of Eu3+ and Cs+ have been discussed using five kinetic models namely, pseudo-first-order model, pseudo-second-order model, Elovich equation, intraparticle diffusion model, and modified Freundlich equation that have been tested in order to analysis the experimental data. Kinetic parameters and correlation coefficients were determined. It was shown that the second-order kinetic equation could describe the sorption kinetics for two metal ions. The metal uptake process was found to be controlled by intraparticle diffusion. Thermodynamic parameters, such as ΔH, ΔG and ΔS, have been calculated by using the thermodynamic equilibrium coefficient obtained at different temperatures. The obtained results indicated that endothermic nature of sorption process for both 152+154Eu and 134Cs onto sawdust.

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Abstract  

Instrumental neutron activation analysis (INAA) based on a nuclear reactor and proton induced X-ray emission (PIXE) based on a 2 Me V Van de Graaff accelerator were used to analyse different environmental samples including coal, sawdust, fly ash and landfill materials. These samples represent a large component of the solid waste being buried in the ground, and may be a potential source of toxicity which can have not only adverse effects on the soil and ground water, if diffused during leaching processes, but may also be transferred to humans through the food chain. Both techniques were employed to determine trace element concentrations in these matrices. The concentration of 30 elements were detemined, namely Na, Mg. Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Cd, Ba, La, Sm, Eu, Tb, Ho, Yb, Hf, Ta and Th. The detection limits in the various sample matrices were calculated and a comparison was made for those elements commonly detected by both techniques.

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Abstract  

This study described adsorption of uranium(VI) by citric acid modified pine sawdust (CAMPS) in batch and fixed-bed column modes at 295 K. The equilibrium adsorption data were analyzed by Langmuir, Freundlich, Koble–Corrigan and Dubinin–Radushkevich isotherm models. The results indicated that the Langmuir and Koble–Corrigan models provided the best correlation of the experimental data. The Elovish model was better to fit the kinetic process, which suggested that ion exchange was one of main mechanism. The effective diffusion parameter D i values indicated that the intraparticle diffusion was not the rate-controlling step. In fixed-bed column adsorption, the effects of bed height, feed flow rate, and inlet uranium (VI) concentration were studied by assessing breakthrough curve. The Thomas, the Yan and the bed-depth/service time (BDST) models were applied to the column experimental data to determine the characteristic parameters of the column adsorption. The results were implied that CAMPS may be suitable as an adsorbent material for adsorption of uranium (VI) from an aqueous solution.

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Romanian coal (bituminous coal from Jiu Valley and lignite from Oltenia basin) and biomass (corn and beech sawdust) was performed in order to understand the characteristics and behaviour of the materials further used in the processes of co-firing and biogas

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, 29 ]. In this work, combustion kinetics of WCS is investigated using TG under the temperature programmed conditions. The combustion characteristic of WCS is compared with sawdust and Baoji coal; effects of O 2 concentration, particle diameter

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Efficacy of three bio-insecticides (i.e. Spinosad, Beauveria bassiana and Metarhizium anisopliae), three inert dusts (i.e. diatomaceous earth, sugar beet wastes and sawdust) and modified atmospheres as alternatives to methyl bromide against adults Sitophilus oryzae on wheat was investigated in laboratory bioassays. Results showed that spinosad was the most effective bio-insecticide against S. oryzae at all exposure periods. Likewise, diatomaceous earth caused the highest mortality percentage compared to the other tested inert dusts. A three and five days exposure periods were adequate to completely kill S. oryzae under modified atmospheres containing 80% and (40 and 60%) CO2 gas in the air, respectively. Therefore, spinosad, diatomaceous earth and modified atmospheres could be consider eco-friendly control methods and promising alternatives to conventional pesticides, as they have low mammalian toxicity and low or zero residual effects in food.

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Abstract  

Fears of climate change and increasing concern over the global warming have prompted a search for new, cleaner methods for electricity power generation. Technologies based on utilising biomass are attracting much attention because biomass is considered to be CO2 neutral. Co-firing of biomass fuels with coal, for example, is presently being considered as a mean for reducing the global CO2 emissions. Biomass is also applied in thermal conversion processes to produce fuels with higher calorific values and adsorbents. In any case, thermal decomposition is essential stage where volatiles and tars are evolved followed by consequent heats of reactions. In this work sawdust biomass samples were selected in order to study their thermal conversion behaviour. Heats of decomposition for each sample were measured during continuous heating at a prescribed heating rate under inert atmospheric conditions. The decomposition generally commenced in all samples at 150C and was completed at 460C in a series of endo and exothermic reactions influenced by its lignin and cellulosic content. Single biomass sample was subjected to heating rates ranging from 10 to 1000C min-1 and the effect of heating rate on decomposition was studied. The origin of reactions for each thermal sequence is herein discussed in detail.

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fruiting of Lentinula edodes on supplemented sawdust. FEMS Microbiol Lett 201 , 111–115 (2001). Royse D. J. Transcriptional regulation of laccase and cellulase genes during

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