Iip Izul Falah

The kinetics of the hydrolysis of organophosphorus and carbamate pesticides in water and aqueous base buffers

Hydrolysis rate constants in neat water (k‘w) and in base buffers (kb) for a number of organophosphorus insecticides and carbamates are computed from pseudo first‐order rate constants, using a simple regression model. The log‐log correlation between k‘w and kb values is evaluated.

Synthesis of mesoporous carbon using gelatin as source of carbon by hard template technique and its characterizations

Synthesis of mesoporous carbon using gelatin as source of carbon by hard template technique (endotemplating) and its characterizations had been investigated. The mesoporous silica (SBA-15) as a template was reacted with the gelatie in a H2SO4 solution. The template-polymer composite was then pyrolyzed under a nitrogen flow at 900 °C for 3 h to carbonize the polymer and finished by silica removal from the composite using NaOH solution at temperature of 70 °C The properties of samples were characterized by N2 adsorption- desorption isotherms, transmission electron microscopy (TEM), Fourier Transformation Infra Red Spectroscopy (FTIR), energy dispersive X-ray (EDAX) and Differential Thermal Analysis-Differential Scanning Calorimetry (DTA-DSC). The results showed that the ordered mesoporous carbon was obtained after dehydration, pyrolysis and silica removal process. The presence of nitrogen atoms in the gelatin as the precursors of carbon improved the thermal stability of the carbon. The mesoporous carbon sample have high content of carbon (85 wt.%) and thermal stabliity (up to 1400 °C), specific surface areas of 580 m 2 /g, total pore volumes of 0,5 cm 3 /g, and pore diameter of 3,8 nm.

Peak dispersion and hydrolysis kinetics of N‐methylcarbamates in packed‐bed and coiled capillary reactors

The Chromatographic and kinetic performance of the hydrolysis of some N‐methylcarbamates in (glass bead) packed‐bed and coiled open capillary reactors is examined, using sodium hydroxide solutions in methanol + water mixtures at about 95°C. The efficiency of the hydrolysis to methylamine in these reactors is evaluated with kinetic in vitro data. Finally, the reaction dispersion in an RP‐18/TBA‐OH solid‐phase reactor is described in terms of a simple model and the utility of this reactor for carbamate hydrolysis is briefly discussed.

Separation, activation and quantitation of organophosphorus insecticides in the TLC‐EI technique

The most important aspects of the TLC‐EI analysis method for organophosphorus pesticide (OPs) residues are examined. Special attention is paid to the activation of the OPs with bromine, hypochloric acid and m‐chloroperbenzoic acid. The effect of the various activation methods and AChE sources on the detection sensitivity is briefly reviewed. Finally, some quantitative results, obtained after in vitro activation with m‐chloroperbenzoic acid, are presented.

Hydrocracking of waste lubricant into gasoline fraction over CoMo catalyst supported on mesoporous carbon from bovine bone gelatin

The hydrocracking of waste lubricant into gasoline fraction was carried out using CoMo catalyst supported on mesoporous carbon. The carbon was synthesized using bovine bone gelatin and SBA-15 as a template. The metals were loaded onto the carbon by wet impregnation method. The total metal content of catalyst was prepared into two different amounts which were labelled as CoMo/MCG1 and CoMo/MCG2. Catalytic activity and selectivity were evaluated in hydrocracking of waste lubricant at 450, 475, and 500 °C, and lubricant/catalyst weight ratio of 50, 100, 200, 300, and 400. The result revealed that acidity and specific surface area of the catalyst played an important role in determining the catalytic performance in the hydrocracking of waste lubricant. The highest percentage of gasoline fraction was 58.09%, produced by hydrocracking of waste lubricant at 475 °C and lubricant/catalyst weight ratio of 300 using CoMo/MCG2 catalyst.

Preparation of Nickel/Active Carboncatalyst and its Utilization for Benzene Hydrogenation

The research on the preparation of nickel catalyst impregnated on active carbon by two methods has been carried out. The impregnation of Ni metal was done using nickel(II) chloride as a precursor. The impregnated of Ni metal on samples in A method was made in varying of percentage i.e., 0.5, 1.0 and 2.0% (w/w) as the weight proportion of Ni to active carbon and NiCl 2 . 6 H 2 0. The concentration of Ni that would be impregnated on samples in B method was made close to Ni content of samples in A method determined by atomic adsorption spectrometry. Preparation of nickel/active carbon catalyst with A method was done with dipping the active carbon in the nickel(II) chloride solution followed by filtering and then drying at 110 °C for 4 hours, and then calcination by flowing nitrogen and reduction by hydrogen, each at 400 °C at 4 hours. The treatments made on samples in A method was also done on samples in B method, the only difference was evaporating all of precursor solution after dipping active carbon in that precursor solution was done in B method. The characterization includes: iodium adsorption test, determination of nickel content by means of atomic adsorption spectrometry, and acidity by adsorption of ammonia methods. Test of catalyst activity was done by means of hydrogenation of benzene to cyclohexane at 150, 200 and 250 °C, the pressure of 1 atm and the flow rate of hydrogen 6 mL/minute. The products were analyzed by gas chromatographic method. The results show that A method produced a catalyst with relatively low nickel content. However the acidity and ability to convert benzene to cyclohexane were relatively high and it increased as increasing the content of nickel. The temperature of the reaction was achieved at 250 °C which gave the yield on conversion of 25.3678%. The catalyst obtained by B method in the same condition of hydrogenation gave only smaller results.