Kimia organologam

Dalam Buku ini pembaca diperkenalkan dengan satu cabang ilmu kimia organologam iaitu kimia bagi sebatian yang mengandungi unsur logam yang berikatan terus dengan atom karbon pada ligan. Bidang ini mengaitkan dua bidang kimia iaitu kimia tak organik dan kimia organik yang mana ilmu pengetahuan dalam kedua-dua bidang diperlukan untuk memahami dengan lebih jelas bidang ini. Tajuk-tajuk meliputi pengenalan asas kepada sebatian organologam yang meliputi latar belakang, penamaan, pengkelasan sebatian organologam. Seterusnya penyediaan, struktur dan tindak balas beberapa sebatian organologam terpilih dikemukakan. Akhir sekali pembaca didedahkan kepada sebatian organologam dalam industri yang berkaitan dengan kehidupan kita seharian dalam menangani masalah dalam bidang pertanian, penternakan, pengawetan kayu, perubatan dan sebagainya. Penulis mengharapkan dengan terbitnya buku ini, dapat menambahkan bilangan buku dalam Bahasa Melayu peringkat tinggi di pasaran bagi kegunaan pelajar-pelajar tahun tiga di Universiti

Degradasi Larutan Pewarna Azo Tekstil Menggunakan Sistem Heterogenan O3, O3/UL, O3/TIO2/UL DAN O3/H2O2/UL

Rawatan larutan pewarna azo tekstil, Sumifix Supra Blue BRF 150% Gran (SSBBRF) melibatkan sistem yang berbeza, O3, O3/UL, O3/TiO2/UL dan O3/H2O2/UL telah dikaji. Keputusan yang diperoleh menunjukkan bahawa degradasi larutan SSBBRF melalui sistem pengoksidaan berasaskan ozon adalah lebih efektif berbanding dengan sistem pemangkinanfoto. Darjah degradasi keserapan dan warna yang tinggi serta degradasi COD dan TOC yang ketara, menunjukkan bahawa sistem pengoksidaan yang berasaskan ozon berupaya memecahkan pewarna azo dalam air tercemar kepada spesies yang lebih terbiorawat. Keputusan yang diperoleh juga menunjukkan bahawa sistem pengozonan (O3 sahaja dalam keadaan gelap), dan sistem gandingan pengozonanfotopemangkinanfoto (O3/TiO2/UL) tidak menunjukkan perbezaan kadar degradasi pewarna azo yang ketara berbanding sistem pengozonanfoto (O3/UL) tetapi penambahan hidrogen peroksida (H2O2) ke dalam sistem O3/UL mampu meningkatkan lagi kadar degradasi pewarna azo. Perbandingan keupayaan sistem yang dikaji bagi degradasi pewarna SSBBRF adalah mengikut urutan: O3/H2O2/UL > O3/UL > O3/TiO2/UL > O3 > TiO2/UL. Proses pendegradasian pewarna SSBBRF mematuhi kinetik tindak balas tertib pertama pseudo dengan nilai pemalar kadar, k, dari julat 0.20 min–1 hingga 0.24 min–1 untuk 20 minit yang pertama

Effect of calcium and iron doping over MoO3-PO4/Al2O3 catalyst in oxidative desulfurization of Malaysian diesel

The catalytic oxidative desulfurization (Cat-ODS) process has emerged as a new technology to achieve ultra-low sulfur levels in diesel fuels. The effect of calcium and iron dopant in MoO3-PO4/Al2O3 catalyst were tested on desulfurization reaction at ambient condition. The oxidizing reagent used was tert-butyl hydroperoxide (TBHP) and dimethylformamide (DMF) acted as an extraction solvent. A commercial Petronas diesel with 440 ppmw of total sulfur was employed to evaluate the elimination of sulfur compounds. The result obtained revealed that Fe/MoO3-PO4/Al2O3 catalyst gave superior performance towards desulfurization. The Fe/MoO3-PO4 catalyst was able to reduce the sulfur in commercial diesel from 440 to 79 ppmw with 82% of total sulfur removal while Ca/MoO3-PO4/Al2O3 catalyst only achieved 76% of sulfur removal. Ammonia temperature programme desorption (TPD) analyses showed that the Fe/MoO3-PO4/Al2O3 catalyst contained both strong and weak acid sites while field emission scanning electron microscopy (FESEM) micrograph illustrated well-dispersed homogeneous structure. The mechanistic study showed that it was depended on the type of dopant as the Fe/MoO3-PO4/Al2O3 catalyst tended to form sulfone in the oxidative desulfurization reaction meanwhile, the sulfoxide formation was dominated in the oxidative desulfurization reaction using Ca/MoO3-PO4(10:90)/ Al2O3 catalyst. The results obtained showed that Fe/MoO3-PO4(10:90)/Al2O3 catalyst can be used as a potential catalyst for the removal of sulfur in Malaysian diesel to achieve Euro IV diesel

Catalytic oxidative desulfurization of Malaysian diesel utilizing palm kernel shell activated carbon supported cerium/iron oxide

Existing technique of hydrodesulfurization (HDS) is no longer applicable in achieving Euro IV standard diesel due to the high operational cost, low efficiency and high operating temperature in hydrogen gas atmosphere. Due to these drawbacks, the utilization of the catalytic oxidative desulfurization (CODS) was introduced to complement the HDS process. In this study, the performance of activated carbon supported cerium and iron oxide catalysts were investigated using tert-butyl hydroperoxide (TBHP) as oxidizing agent and N,N-dimethylformamide (DMF) as extraction solvent. The effect of dopant ratio, calcination temperature, number of loading and desulfurization treatments were studied. The results showed that effective dopants ratio (% atomic weight) of Ce/Fe (80:20) prepared by wet impregnation method calcined at 400°C was the best catalyst in this study. Nitrogen adsorption/desorption measurement of CeO2/Fe2O3 (80:20)-AC exhibited the characteristic of microporous structure with Type 1 IUPAC isotherm. The micrograph of the field emission scanning electron microscopy (FESEM) illustrated an inhomogeneous distribution of various particle sizes composed of cerium and iron oxides as been proven by energy dispersive X-ray analysis (EDX) on the surface of prepared bimetallic oxides catalyst. The deep desulfurization of Malaysian commercial diesel fuel contained 440 ppm sulfur was achieved after oxidation with two cycle extraction process with 98% total sulfur removal to produce Green Diesel contained 8.8 ppm sulfur has been measured using GC-FPD. The results obtained has proven that CeO2/Fe2O3 (80:20)-AC can be used as potential catalyst for the removal of sulfur in the Malaysian diesel towards achieving the green diesel production

Biodiesel production via transesterification of low grade cooking oil over heterostructure nano particles of ni/mg/al2o3 catalyst

Biodiesel which were synthesis from transesterification reaction in the present of heterogeneous base catalyst has been intensively studied over the last decades. This catalyst has an excellent result in producing high percentage conversions of biodiesel without further purification and cleaning process which contribute to the water pollution and high water content in biodiesel product. So, this study was conducted to synthesize and characterize series of heterostructure Ni/Mg/Al2O3 catalysts with different parameters to test their effectiveness towards the catalytic transesterification reaction. Series of Ni/Mg/Al2O3 catalysts were synthesized by wetness impregnation method supported on γ-alumina beads. Three parameters were studied include calcination temperatures, dopant ratios to base and numbers of alumina coating. The activity of the catalyst in transesterification reaction was evaluated at 65ºC of reaction temperature, 3 hours of reaction time, 6% w/w of catalyst loading and 1:24 molar ratio of oil to methanol. The potential catalyst was characterized by N2 Adsorption Analysis, TEM (BIO-TEM) and CO2-TPD. Meanwhile, the performance of the catalyst was evaluated using GC-FID. From the data obtained, Ni/Mg(20:80)/Al2O3 catalyst calcined at 800°C and three times alumina coating have the highest weak and moderate basic sites that contribute to the highest percentage conversion of low grade palm oil to biodiesel compared to others. Besides that, BIO-TEM result showed that the particle was non-homogeneous shape with a mixture of square sheet and one dimensional heterostructure nano-rod particles was observed. The data obtained from CO2-TPD and N2 Adsorption Analysis (NAA) prove that high basicity of the Ni/Mg(20:80)/Al2O3 catalyst (2.80 mmol/g) and high surface area (125 m2/g) had led to 78.53% of biodiesel conversion

The effect of noble metals on catalytic methanation reaction over supported Mn/Ni oxide based catalysts

Carbon dioxide (CO2) in sour natural gas can be removed using green technology via catalytic methanation reaction by converting CO2 to methane (CH4) gas. Using waste to wealth concept, production of CH4 would increase as well as creating environmental friendly approach for the purification of natural gas. In this research, a series of alumina supported manganese-nickel oxide based catalysts doped with noble metals such as ruthenium and palladium were prepared by wetness impregnation method. The prepared catalysts were run catalytic screening process using in-house built micro reactor coupled with Fourier Transform Infra Red (FTIR) spectroscopy to study the percentage CO2 conversion and CH4 formation analyzed by GC. Ru/Mn/Ni(5:35:60)/Al2O3 calcined at 1000°C was found to be the potential catalyst which gave 99.74% of CO2 conversion and 72.36% of CH4 formation at 400°C reaction temperature. XRD diffractogram illustrated that the supported catalyst was in polycrystalline with some amorphous state at 1000°C calcination temperature with the presence of NiO as active site. According to FESEM micrographs, both fresh and used catalysts displayed spherical shape with small particle sizes in agglomerated and aggregated mixture. Nitrogen Adsorption analysis revealed that both catalysts were in mesoporous structures with BET surface area in the range of 46-60m2/g. All the impurities have been removed at 1000°C calcination temperature as presented by FTIR, TGA-DTA and EDX data

Binary metal oxides supported on gamma-Al2O3 for application in transesterification of low-grade cooking oil

Recently, the production of biodiesel has increased greatly due to the less harmful effects of this fuel towards the environment which is sourced from renewable materials compared to a conventional diesel. The series of solid base catalysts, binary metal oxide (Cu/Zn) were synthesized by the modified wet impregnation method supported on γ-Al2O3.The investigation of Cu/Zn/γ-Al2O3 catalyst on the calcination temperature, copper loading and number of alumina coatings had significantly affected the catalytic performance. The optimum conditions from experimental data were achieved with 10 wt.% of Cu loading of Cu/Zn/γ-Al2O3 catalyst calcined at 800°C with 3 times number of alumina coatings exhibited the highest fatty acid methyl ester (FAME) yields, 87.07% at mild reaction conditions (65°C, atmospheric pressure, 1:20 methanol-to-oil molar ratio, 10 wt.% of catalyst loading and 2 hours of reaction time). The physicochemical properties studied by BET surface area of Cu/Zn(10:90)/γ-Al2O3 catalyst calcined at 800°C which gave high surface area, 149.32 m2/g. FESEM-EDX analysis of Cu/Zn(10:90)/γ-Al2O3 catalyst indicated the amorphous in structure with undefined shapes and mixture of larger and smaller particles sizes. The production of biodiesel and the percentage conversion of FAME was analyzed by using GC-FID in the presence of methyl palmitate, cis-9-oleic acid methyl ester and methyl linoleate

Photocatalytic Degradation of Sumifix Supra Blue BRF

Oxidative degradation of textile azo dye, Sumifix Supra Blue BRF (SSBBRF) in aqueous solution of suspended TiO2 with the presence of UV irradiation and H2O2 has been studied. The addition of H2O2 in the photocatalytic system can enhance the degradation degree of SSBBRF solution. However, H2O2 concentration that more that 5 x 10-4 mol/L would detriment the degradation process. Study on the kinetics of oxidative degradation of SSBBRF solution in the TiO2/UV or TiO2/H2O2/UV systems showed that the system were following the pseudo-first order reaction with the rate constant, k of the optimal system as 0.0434 min-1

Optimization of praseodymium oxide based catalysts for methanation reaction of simulated natural gas using Box-Behnken design

Malaysia energy demand on natural gas is increasing, leading to the purification of sour natural gas through the removal of carbon dioxide using catalytic conversion technique. Praseodymium oxide is preferred due to its properties which are suitable in the production of catalysers, polish glass and also as alloying agent. Therefore, a series of praseodymium oxide catalyst was prepared by incipient wetness impregnation method and was calcined at 400oC for 5 hours during screening reaction. The experimental Box-Behnken design was applied for optimizing the parameters in catalytic methanation reaction. The optimum parameters were found to be compatible with the experimental result which showed that Ru/Mn/Pr (5:35:60)/Al2O3 calcined at 800°C with 65% Pr loading and 7 g of catalyst dosage gave 96% of CO2 conversion, determined using FTIR, and yielded about 41% of CH4 at reaction temperature of 400°C. In the stability test, the catalyst’s performance showed an increase and was stable up to 7 hours with 96% of CO2 conversion. X-ray Diffraction (XRD) analysis showed an amorphous structure while Field Emission Scanning Electron Microscope (FESEM) illustrated the presence of small and dispersed particles with undefined shape covering the catalyst surface. EDX analysis revealed that when calcination temperature increased, the mass ratio of Ru increased. Meanwhile Nitrogen Adsorption (NA) analysis revealed that Ru/Mn/Pr (5:35:60)/Al2O3 catalyst attained surface area of 134.39 m2/g

Development of bimetallic and trimetallic oxides doped on molybdenum oxide based material on oxidative desulfurization of diesel

Catalytic oxidative desulfurization (Cat-ODS) activities of thiophenic sulfur were compared using alumina supported of mono-, bi- and trimetallic oxide molybdena based catalysts, prepared by incipient wetness impregnation. The aim of this study was to inquire on the possibility of supported trimetallic oxide catalysts for deep Cat-ODS process. The prepared catalysts were characterized by nitrogen adsorption, X-ray diffraction, field emission scanning electron microscopy and transmission electron microscopy, and tested in the ODS of model thiophene, dibenzothiophene and 4,6-dimethyldibenzothiphene, as well as on commercial and crude diesel. It was found that the addition of dopant and co-dopant toward MoO3/Al2O3 catalysts increased significantly the selectivity of catalytic performance in the order: mono-90% of sulfur was removed in both commercial and crude diesel under similar reaction conditions. Reproducibility test showed that the catalyst has higher catalytic activity and could be repeatedly used with little change after five cycles