Zatil Amali Che Ramli

Recovery and Purification of Crude Glycerol from Vegetable Oil Transesterification

This article reviews the purification techniques involved in producing high-purity glycerol in the biodiesel industry. Utilization of glycerol by-products (contains less than 50 wt.% of glycerol and the remaining contents are water, salts, unreacted alcohol and catalyst) in biodiesel production affords greener and less costly processes. Research has focused on several purification steps that are capable of producing high-purity glycerol. Various new techniques for purifying glycerol promise better quality and lower cost and technologies are required to fulfil increasing worldwide demand. Neutralization, ultrafiltration, the use of ion exchange resins, vacuum distillation and other methods have been utilized in single or multiple stages. Recent studies have demonstrated that the combination of more than one technique produces high-purity glycerol (>99.2%). Purifications cost can be as low as 0.149 USD

Photocatalytic degradation of methylene blue under UV light irradiation on prepared carbonaceous TiO2.

/kg. For many applications, high-purity glycerol is more useful. In some cases, it is even necessary, particularly in the fields of hydrogen production, methanol production, pharmaceuticals and food additives.

Magnesium oxide nanoparticles on green activated carbon as efficient CO2 adsorbent

This study involves the investigation of altering the photocatalytic activity of TiO2 using composite materials. Three different forms of modified TiO2, namely, TiO2/activated carbon (AC), TiO2/carbon (C), and TiO2/PANi, were compared. The TiO2/carbon composite was obtained by pyrolysis of TiO2/PANi prepared by in situ polymerization method, while the TiO2/activated carbon (TiO2/AC) was obtained after treating TiO2/carbon with 1.0 M KOH solution, followed by calcination at a temperature of 450°C. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TG-DTA), Brunauer-Emmet-Teller (BET), and UV-Vis spectroscopy were used to characterize and evaluate the prepared samples. The specific surface area was determined to be in the following order: TiO2/AC > TiO2/C > TiO2/PANi > TiO2 (179 > 134 > 54 > 9 m2 g−1). The evaluation of photocatalytic performance for the degradation of methylene blue under UV light irradiation was also of the same order, with 98 > 84.7 > 69% conversion rate, which is likely to be attributed to the porosity and synergistic effect in the prepared samples.

Peranan spesies kromium aktif pada penyokong yang berbeza dalam tindak balas penyahhidrogenan gas propana

This study was focused on carbon dioxide (CO{sub 2}) adsorption ability using Magnesium oxide (MgO) nanoparticles and MgO nanoparticles supported activated carbon based bamboo (BAC). The suitability of MgO as a good CO{sub 2} adsorbent was clarified using Thermodynamic considerations (Gibbs-Helmholtz relationship). The ΔH and ΔG of this reaction were − 117.5 kJ⋅mol{sup −1} and − 65.4 kJ⋅mol{sup −1}, respectively, at standard condition (298 K and 1 atm). The complete characterization of these adsorbent were conducted by using BET, XRD, FTIR, TEM and TPD−CO{sub 2}. The surface areas for MgO nanoparticles and MgO nanoparticles supported BAC were 297.1 m{sup 2}/g and 702.5 m{sup 2}/g, respectively. The MgO nanoparticles supported BAC shown better physical and chemical adsorption ability with 39.8 cm{sup 3}/g and 6.5 mmol/g, respectively. The combination of MgO nanoparticle and BAC which previously prepared by chemical method can reduce CO{sub 2} emissions as well as better CO{sub 2} adsorption behavior. Overall, our results indicate that nanoparticles of MgO on BAC posses unique surface chemistry and their high surface reactivity coupled with high surface area allowed them to approach the goal as an efficient CO{sub 2} adsorbent.

Investigation of Photocatalytic Activity of TiO2-PANi Nanocomposites

Dehydrogenation of propane (DHP) was studied over a series of Cr2O3–Al2O3 and Cr2O3-SiO2 catalysts, prepared by incipient wetness impregnation and sol gel (SG) method, respectively, to gain a better understanding of the nature and distribution of chromium (Cr) species and their catalytic function. To this end, the catalysts were characterized by N2-physisorption and X-ray diffraction (XRD). N2-physisorption analysis of Cr2O3-SiO2 showed the relatively higher surface area of 391.1 m /g, compared with Cr2O3-Al2O3 of 224.3 m /g. The combination method of sol gel and sonothermal also produced smaller particles size of catalyst with higher microporosity of 23.5% and smaller pores size of 6 nm. The good surface properties of Cr2O3-SiO2 enabled the high conversion of propane of 55% at 550 °C. At higher temperature of 600 °C, the Cr species might be reduced into lower oxidation state and inhibit the catalytic behavior to produce hydrogen.

Adsorption-desorption of CO2 on different type of copper oxides surfaces: Physical and chemical attractions studies

In this paper the photocatalytic activity of TiO2-PANi nanocomposites prepared using two different In-situ polymerization methods have been investigated. The same pressure, temperature, precursors, mole ratio, and solvent have been employed for preparation of nanocomposites. The synthesized nanocomposites were characterized by FESEM, XRD and FTIR. Results revealed the successful preparation of TiO2- PANI nanocomposites. TiO2-PANi nanocomposite synthesized using method 2 showed very well dispersed TiO2 nanoparticles on the surface of PANi. There is no agglomeration of TiO2 nanoparticles in PANi matrix. The photocatalytic activities of nanocomposites were evaluated by using photo degradation of Methylene Blue (MB) in aqueous solution under UV irradiation. These nanocomposites exhibit much higher photocatalytic activity compared with TiO2.