Papers by Keyword: BET

Abstract: Multi-walled carbon nanotubes (MWCNTs) probably hold with each other and agglomerated due to van der Waals force. Functionalized process was used to reduce its ability to agglomerate and to increase dispersion in solution. The present work is focused on the microwave irradiation in order to achieve rapid functionalization of MWCNTs compared with other known techniques. The power of microwave radiation was selected by investigating the structural integrity of the samples by X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FE-SEM), while BET surface area measurement was used to measure the MWCNT surface area before and after treatment. The dispersion test in the solution was performed to determine the separation capability of untreated MWCNTs and f-MWCNTs.

Abstract: Chemical admixtures are frequently used to regulate the setting and strength development of concrete materials. In this study, tricalcium silicate (C₃S) was used as a model of the cement system, and the influence of calcium chloride, an extremely useful accelerator, on C₃S hydration and the pore structure of hardened C₃S paste were investigated by the combination of the techniques of differential scanning calorimetry (DSC) and the N₂ adsorption (BET). The results indicated that the addition of calcium chloride would significantly shorten the pre-induction and induction periods and enhance the specific surface area and porosity of hardened C₃S paste. However, the presence of CaCl₂ has little effect on the pores, with a width ranging from 2.5 nm to 5 nm. DSC technique has an advantage of measuring continuously the process of C₃S hydration by changes of free water in hydrated C₃S.

Abstract: The set of studies on modified superficial layer friction pair parts made of X155CrVMo12-1steel was discussed. The said layer is produced according to the duplex process of nitriding and oxidation and is investigated using methods of metallography, X-ray diffraction analysis and micro-hardness measurement based on the oblique and transverse polished sections of the studied surfaces. The results produced proved the duplex process efficiency.

Abstract: The physical and chemical properties of "loose" manganese ore of Ulu-Telyak Deposit of the Republic of Bashkortostan for the possibility of its use as an effective sorbent for purification of exhaust gases of metallurgical, chemical, oil refining, mining and other industries are studied. Analyses were carried out on the phase composition, chemical composition, determined the specific surface area of the pores and thermogravimetric method of water content. The process of sorption of a gas mixture containing hydrogen sulfide, methyl and ethyl mercaptans was also studied. The results of the experiments concluded that the prospects of using this "loose" manganese ore for the sorption of sulfur-containing gases.

Abstract: Introducing or impregnating Mg(OH)₂ onto activated carbon is a promising path for wastewater treatment of uptake (removal) uranium from aqueous solution. The present study aims to synthesize and characterize Mg(OH)­₂-impregnated activated carbon from coconut shell. The introducing or impregnating Mg(OH)₂ into treated biochar by activation method using various impregnation ratio (IR) of MgCl₂ (IR = 0.5; 1.0; 2.0). Characterization of functional groups in produced activated carbon was conducted with the aid of FTIR spectroscopy. The presence of O-H or Mg(hydroxyl) bond was confirmed by FTIR analysis at 3343.50 cm^-1 with the highest intensity of the obtained peak at impregnation ratio (IR) 2.0. Due to the surface area is one of the important factors that control a material’s ability to adsorb contaminations, the surface area of activated carbon was measured about 353-358 m²/g by BET method. To indicate that introducing or impregnating Mg(OH)₂ or Mg(hydroxyl) into treated carbon is successfully work, the presence of Mg (%w) in activated carbon was performed using X-Ray Fluorescence Analysis with the highest Mg presence about 28.587 (%w) at impregnation ratio (IR) 2.0.

Abstract: The most critical parameter of palm oil mill effluent (POME) is chemical oxygen demand (COD mg/L). The adsorption of COD mg/L from raw POME using activated cow bone powder has been investigated. The raw POME contains 4.786 g/L of COD, which has to be treated effectively before discharge. Batch experiments were conducted at fixed condition of pH, contact time and speed at different weight dosages for different particle sizes of 75, 150 and 300μm. The result obtained showed a similar adsorption pattern for the particle sizes, the optimum removal was obtained at 150 μm at 0.025g/L with 71% removal efficiency, there was no further significant diference after the adsorption at this stage. The BET adsorption model was adopted to describe the experimental isotherm and isotherm constants for the optimum particle size. The equilibrium data fitted well to the BET model. The hydrophobic behaviour of the CBP proved by the WDPT analysis influenced the removal of COD mg/L on CBP.

Abstract: Nearly 40% of the world gas reservoir contains high level of CO₂ that stance problems to development. The discovery of natural gas field with CO₂ content of as high as 87% in Malaysia poses new challenges in terms of the CO₂ separation processes. This research work investigates the potential of MIL(Materials Institute Lavoisier)-101 as CO₂ capture and storage candidate by conducting an experiment with different pressure between the synthesised and modified MIL-101 using Multi-wall carbon nano tubes (MWCNTs). To investigate the effect of the MWCNTs in MIL-101 towards CO₂ adsorption performance. The synthesized MOFs were characterized using scanning electron microscopy (SEM) for surface morphology, Thermogravimetric analysis (TGA) for thermal stability, X-ray diffraction (XRD) for crystals plane, Brunauer-Emmet-Teller (BET) for surface area and CO₂ adsorption performance. The result had showed that the modified MIL-101 enhanced the CO₂ adsorption compared to the pure MIL-101. MWCNT@MIL-101 showed the adsorption of CO₂ uptake is 0.0029mmole^-1/g at 100kPa.

Abstract: In this work, the Fe_xO_y catalysts were prepared by the co-precipitation method. The catalysts were characterized by X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), and Brunauer-Emmett-Teller (BET) surface analysis. From XRD results, the Fe_xO_y with the wastewater to coagulant ratio of 1:2 catalyst (Fe_xO_y-1:2) calcined at 600 °C for 6 h showed the presence of the wustite (FeO) form. XANES analysis showed the phase of FeO in Fe_xO_y-1:2 calcined at 600 °C for 6 h which corresponded to the result from XRD. The Fe_xO_y 1:1 catalyst had higher specific surface area and larger total pore volume compared to the Fe_xO_y 1:2 catalyst.

Abstract: There is a growing need of counter assessing the increase of releases greenhouse gases such as carbon dioxide by researching an alternative technology that can help to reduce carbon dioxide content in atmosphere. This research work investigates the potential of MIL-53 as CO₂ capture and storage candidate by conducting an experiment with different pressure between the synthesised and modified MIL-53. To investigate the effect of the Multi-wall carbon nanotubes (MWCNTs) and carbon nanofibers (CNFs) in MIL-53 towards CO₂ adsorption performance. The synthesised samples were characterized by Fourier Transform Spectroscopy (FTIR) and Brunauer, Emmett and Teller (BET) techniques. A significant change is observed in the region of the aromatic deformation vibrations due to the different substitution patterns of the aromatic ring. BET surface area for MWCNT@MIL-53 is higher than CNF@MIL-53 and MIL-53. MWCNTs showed the adsorption of CO₂ uptake is 0.3mmole^-1/g at 100Kpa.

Abstract: In the present study, Zn-hydroxyapatite (Zn-HA) was synthesized, the powder was thermally treated at different temperatures and then characterized. The Zn-HA powder was characterized mainly by FTIR and XRD, but have been performed investigations like SEM, BET and size distribution. The addition of ZnO in hydroxyapatite causes alleged interactions with the existing groups in HA, which amend the corresponding signals to these groups in the IR spectra. X-ray diffractograms for samples (untreated and heat-treated) have been recorded and microstructural parameters for the all samples have been calculated. The obtained average sizes of the crystallites and the network tensions support the idea that Zn-HA powders are nanostructured. The SEM images and size distributions for Zn-HA indicate a cluster of crystals with nanometer-scale of the population-base. Was determined the adsorption-desorption isotherms for Zn-HA powder at 100 o C and 800 o C. The dates obtained from the analysis of particle size distribution indicates for the Zn-HA powder an size distribution for granules in the range from 0.05 to 0.3μm