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OALib Journal期刊

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Effects of Molar Ratio, Alkali Catalyst Concentration and Temperature on Transesterification of Jatropha Oil with Methanol under Ultrasonic Irradiation  [PDF]
Amish P. Vyas, Jaswant L. Verma, Nandula Subrahmanyam
Advances in Chemical Engineering and Science (ACES) , 2011, DOI: 10.4236/aces.2011.12008
Abstract: For transesterification of Jatropha oil into biodiesel, ultrasound assisted transesterification seems to be promising in terms of reduction in process time and stages of operation. Effects of process variables such as the catalyst loading, the molar ratio of methanol to oil, reaction temperature and the reaction time were investigated on the conversion of Jatropha oil to biodiesel. The conversion was above 93% under the conditions of 50?C, methanol to oil molar ratio of 9:1, reaction time 30 min and catalyst amount (catalyst/oil) of 1% wt%. A kinetic study of transesterification of Jatropha oil based on ultrasound assisted synthesis is presented in this paper. Rate equation obtained is also presented.
Synthesis of NaX (X = F, Cl, Br, I) Nanoparticles  [PDF]
Elseddik Abdelkader, Steven W. Buckner
Soft Nanoscience Letters (SNL) , 2013, DOI: 10.4236/snl.2013.31005
Abstract:

We report here on the synthesis of nanoparticles (NPs) of sodium halide (NaX; X = F, Cl, Br, I) salts using reverse micelles (water/dioctylsodiumsulfosuccinate/toluene) with the resulting NPs having diameters of 1.5 to 2.5 nm. The initial core of reverse micelle contains a water-soluble salt. After evaporation of the volatile compounds under vacuum (water and toluene), NaX NPs are produced with an AOT surfactant cap. The NaX NPs redisperse in toluene. In contrast to previous syntheses of soluble salt NPs, Na+ ions from the surfactant are found to completely exchange with the salt in the initial core of the reverse micelles. The resulting NPs were analyzed with dynamic light scattering (DLS), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) which confirmed the exchange mechanism. Experimental results are compared and found to be in agreement with the recently published model by Bandopadhyaya and coworkers.

Effect of Alkali Treatment on Heavy Metals Adsorption Capacity of Sewage Sludge  [PDF]
Jianlong Hu, Xiaosong Yang, Linan Shao, Xuwen He, Kunkuo Men
Journal of Geoscience and Environment Protection (GEP) , 2015, DOI: 10.4236/gep.2015.32006
Abstract:

Sewage sludge is the promising raw material for biosorbent preparation. In this work, we evaluated the heavy metals adsorption characteristics of alkali treated sewage sludge (ATSS) by equilibrium studies. The adsorption isotherms were fitted with Langmuir and Freundlich models. Comparing with untreated sewage sludge, the total adsorption capacity (qm) of ATSS (prepared with 0.125 mol/L NaOH) for Cd, Pb, Ni, increased by 0.51, 0.70 and 0.32 mmol/g, respectively. When the NaOH concentration for ATSS preparation increased from 0.125 mol/L to 0.25 mol/L, the qm of ATSS for Pb decreased from 1.05 mmol/g to 0.84 mmol/g. However, when the NaOH concentration increased from 0.25 mol/L to 7.5 mol/L, it showed increasing trend. According to the IR spectra data, the adsorption effect of biosorbent for heavy metals was mainly due to the complexation of -N-H groups and -COOH groups.

Eliminación de patógenos en biosólidos por estabilización alcalina
Torres Lozada,Patricia; Madera,Carlos Arturo; Silva Leal,Jorge Antonio;
Acta Agronómica , 2009,
Abstract: the ca?averalejo wastewater treatment plant (ptar-c) based in cali-colombia, produces almost 100 t-day-1 of biosolids. although do not have heavy metals restrictions, it is class b for high contents of pathogens microorganisms and parasites. the alkali stabilization was done with a 9% of dose (w/w) of quicklime and hydrated lime applied to different 0.5 ton piles of wet biosolids (66.5% humidity) and dry biosolids an environmental temperature (25-31°c) for 72 hours (50.1% humidity). the experiment had a completely randomized design and it was composed by 6 treatments with their respective duplicated. with the alkali stabilization, the ph increments above 12 units during enough time to assure pathogens and parasites reduction in order to achieve a class a material level. on the other hand, the dry biosolids facilitate the conditions for lumps formation that reduce the homogenization of the substrate with the alkali material, which it is and undesirable factor for pathogen reduction.
Degradabilidade in situ da cana-de-a?úcar tratada ou n?o com óxido de cálcio, em novilhas leiteiras Holandês x Gir
Campos, M.M.;Borges, A.L.C.C.;Lopes, F.C.F.;Pancoti, C.G.;Silva, R. Reis e;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2011, DOI: 10.1590/S0102-09352011000600028
Abstract: in situ degradability of sugarcane in natura or added to different levels of calcium oxide (cao) in fed diet, 0.0; 0.5; 1.0 and 2.0% for 24 h in five holstein x gyr heifers, fitted with a rumen cannula.the parameters of rumen degradation of dry matter (dm), organic matter (om), neutral detergent fiber (ndf) and acid detergent fiber (adf) were estimated by adjusting non-linear model to data degradation, and used the parameters obtained in regression analysis, linear and quadratic performed according to the level of inclusion of calcium oxide in diets.the potential and effective degradability, as well as the degradation rates of dm and om were lineraly enhanced with the increasing of the cao levels in diet. the increasing levels of cao in sugarcane diets offered to holstein x gyr dairy heifers lead to a linear enhancement of in situ degradability of dm and om, but does not affect the in situ degradability of fiber fractions.
Comparison of Alkaline Treatment of Lead Contaminated Wastewater Using Lime and Sodium Hydroxide  [PDF]
Sudhakar M. Rao, G. C. Raju
Journal of Water Resource and Protection (JWARP) , 2010, DOI: 10.4236/jwarp.2010.23032
Abstract: A lead-acid storage battery manufacturing industry in India produces several thousand liters of lead con-taminated acidic wastewater on a daily basis and uses hydrated lime to render the lead-contaminated acidic wastewater alkaline (pH = 8.0). Alkaline treatment of the acidic wastewater with lime though a cost-effective method, generates copious amount of lead-contaminated gypsum sludge. Other alkali agents such as sodium hydroxide, sodium carbonate and dolomite are also used for alkali treatment of the acid wastewaters. The present paper compares the relative efficiency of hydrated lime and 0.05 M to 1 M NaOH solutions with re-spect to 1) amounts of sludge produced, 2) immobilization of the soluble lead in the acidic wastewater (AWW) and 3) increase in TDS (total dissolved solids) levels upon treatment of AWW with NaOH solutions and lime. The study also performs equilibrium speciation upon alkaline treatment of AWW with lime and NaOH (sodium hydroxide) solutions using the Visual MINTEQ program to understand the chemical reac-tions occurring during treatment process.
Studies on Transport Properties of Fe3+: Li2O-K2O-CdO-B2O3 Glass System: An Evidence of Mixed Alkali Effect  [PDF]
G. Padmaja, P. Kistaiah
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.46115
Abstract:

The glasses of the type (30 x)Li2O xK2O 10CdO 一 59B2O3 doped with 1 mol% of Fe2O3 were prepared by melt quench technique and their non-crystallinility has been established by XRD studies. The glasses were investigated for room temperature density and electrical conductivity in the temperature range 300 - 523 K and in the frequency range 102 to 105 Hz. The frequency and temperature dependence of conductivity as dielectric constant are presented.

Alkali Catalysis of Different Vegetable Oils for Comparisons of Their Biodiesel Productivity  [PDF]
Ayten Sagiroglu, Hakki Mevlut Ozcan, Sebnem Selen Isbilir, Hatice Paluzar, Neslihan M. Toprakkiran
Journal of Sustainable Bioenergy Systems (JSBS) , 2013, DOI: 10.4236/jsbs.2013.31011
Abstract:

The main advantages of biodiesel are its biodegradability, renewablity, improved nontoxic exhaust emissions and unnecessary alteration of common diesel engines. Today, biodiesel is produced by catalysis of inorganic acids, alkali and free or immobilized lipases with vegetable oil and short chain alcohols. Alkali and acidic catalysts are the most using catalysts for production of biodiesel because of their higher reaction yield and rate. In this study, we have comprised biodiesel productivity of different vegetable oils like sunflower, safflower, canola, soybean, olive, hazelnut, corn oils and waste sunflower oils by alkali catalysis. The transesterification of oils were performed by using NaOCH3 as catalyst at 25°C and at 100°C for 1 h. A defined amount of methanol as 6/1 molar ratio to oil was premixed with the metallic sodium. The amount of metallic sodium in methanol was 1.6 w% of oil mass for all of the crude oils/frying oil. Optimum reaction temperature was found as 25°C. TLC (Thin Layer Choromatography) image and GC (Gas Choromatography) results demonstrates that the dominant fatty acid in safflower, soy bean, sunflower, canola, corn and waste sunflower oil esters was linoleic acid (18:2). Besides it was oleic acid (18:1) for the olive and hazelnut oil esters. When biodiesel productivities of eight different oils were compared, similar results were obtained.

Study of Alkali Metal Corrosion on Heating Surfaces and Bed Material Agglomerate in Biomass-fired Fluidized Bed Boiler  [PDF]
Tuo Chen, Yanfen Liao, Shumei Wu, Xiaoqian Ma, Jinghui Song
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B002
Abstract: The bed material agglomeration and heating surface high-temperature Corrosion Problems of biomass-fired boiler in South China were studied in this work. The inner and outer surfaces of the corrosion sample were investigated by scanning electron microscope (SEM) with Bruker EDX and XRD. Results showed that the outer side of the corrosion sample was mainly composed of alkali chloride deposited ash, sulphide and a small amount of eutectoid; while the inner side of the corrosion sample was still mainly made up of the composition of SUS316, but added with alkali metal, oxygen, chlorine and sulphur elements, appearing as the corrosion products and eutectoid. It was thought that alkali chloride deposit and the reaction with pipe metal to generate low melting point eutectoid on the outer surfaces, or the corrosion reaction through the alkali metal sulphatization process was the main reasons leading to the damage of metal surface oxide film. Chlorine plays a role as haptoreaction in the corrosion process, and transports metal material as the form of chloride from the inner side to the outer side of the pipe surfaces by diffusion, accelerating the corrosion process. Meanwhile, the slag was studied by scanning electron microscope (SEM) with Bruker EDX, and the transformation process of slage was computationally analyzed by FACTSAGE. Results showed that the amount of alkali metal in the agglomerates was little, however, caused a great impact on severe agglomerates. The increase of temperature enhanced the conversion process of alkali metal to molten oxide, especially when the temperature was higher than760℃, the amount of molten product increased sharply. Thus, the temperature control of fluidized bed plays an important role in solving the problem of alkali metal agglomerates; it also reliefs the volatile of alkali metal into gas phase, benefiting the control of heating surface corrosion.
Mineralogy and the Texture of the Basalt in Hail Region, Saudi Arabia  [PDF]
Sana’a Odat
Open Journal of Geology (OJG) , 2014, DOI: 10.4236/ojg.2014.45015
Abstract:

The study is carried out to list mineralogy and texture of the basalt in Hail region. The basalt flows belong to the Arabian Harrat volcanism. Cenozoic volcanism has produced 13, vast, basaltic fields in western Saudi Arabia, covering a total area of about 100,000 sq. km. The volcanism starts in the late Cretaceous time and continues periodically into the Holocene. The basaltic field presently investigated is known as Harrat Al-Hamad (or Harrat As-Shamah) which lies in northwestern Saudi Arabia, and continues northwards into Jordan. Mineralogical analysis of 20 rock samples indicates that the rocks are products of continental intra-plate magmatism; mostly as coarse-grained silica—under saturated olivine-rich alkali basalt. Mineralogical study shows that rocks are olivine, plagioclase, pyroxene, Nepheline and Opaque minerals. They correspond to alkali olivine basalts. Moreover, the main well-defined texture is intergranular, vesicular and amygdaloidal texture.

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