کاربردهای شیمی تجزیه
Mehdi Hosseini; Ebba Adnan Azooz
Abstract
The process of interesterification is one of the most important alternative ways of hydrogenating oils, which is of particular importance by providing the possibility of changing the functional, physical and chemical properties of oils in a favorable way. In this work, a pyrrolidinium-based acidic ionic ...
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The process of interesterification is one of the most important alternative ways of hydrogenating oils, which is of particular importance by providing the possibility of changing the functional, physical and chemical properties of oils in a favorable way. In this work, a pyrrolidinium-based acidic ionic liquid, N-methylpyrrolidinium bisulfate ([Mpyr][HSO4]), was synthesized and characterized, and its catalytic performance was evaluated in the interesterification (glycerolysis) of triglyceride oils. Common analyzing techniques such as Fourier Transfer Infra-red (FTIR) and Nuclear Magnetic Resonance (NMR) techniques were used to catalyst characterization, structure and different bonds evaluation in catalyst structure. The catalytic activity of [Mpyr][ HSO4] during interesterification process of soy oil as raw material of triglycerides and glycerol reagents was investigated. For evaluation of interesterification procedure, the effects of several important parameters such as reaction time and temperature, molar ratio of oil: glycerol and catalyst dosage were investigated. The results obtain showed that the catalyst of [Mpyr][HSO4] is suitable for the interesterification (glycerolysis) of triglyceride oils and it has a conversion of about 97.5%. A simple and accurate titration method was used to evaluate the rate raw materials conversion into ester. Furthermore, in order to reuse the catalyst, the catalyst can be reused up to seven times.
کاربردهای شیمی تجزیه
Negar Gholhovallahi; Ali Sheibani
Abstract
Ion mobility spectrometry is an analytical technique with main advantages such as high sensitivity, fast response and simplicity. The purpose of this work was to determine of mesalazine in different pharmaceutical samples using ion mobility spectrometry with a positive corona ionization source. After ...
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Ion mobility spectrometry is an analytical technique with main advantages such as high sensitivity, fast response and simplicity. The purpose of this work was to determine of mesalazine in different pharmaceutical samples using ion mobility spectrometry with a positive corona ionization source. After obtaining the best instrumental parameters (injection temperature: 230 ºC, cell temperature: 180 ºC, drift voltage: 6800 V, corona voltage: 2400 V, flow rate of drift gas: 600 mL/min and flow rate of carrier gas: 300 mL/min) the linear dynamic range was 1.0–70.0 ng with a determination coefficient, R2=0.9881. The relative standard deviation values were lower than 6.0% (n=5) for the examined range (10.0–60.0 ng) of the drug. The limit of detection and limit of quantitation were 0.3 ng and 1.0 ng, respectively. The capability of the developed method was evaluated for the determination of mesalazine in tablet, capsule, and suppository as pharmaceutical samples. Satisfactory recovery results were obtained in the range of 98.0–103.8%.
