Absorption of SO2 by triethylenetetramine in ether (alcohol)/H2O system

The use of organic solvents to remove SO2 from flue gas has the advantages of low investment cost, convenient operation, high efficiency, and reusability. We prepared three absorbents in this paper, namely tetraethylenetetramine (TETA), triethylenetetramine /triethylene glycol dimethyl ether (TriEDGME), and triethylenetetramine/triethylene glycol dimethyl ether/H2O. The atmospheric bubbling method absorbs SO2. The experimental results show that the three kinds of absorbents formed white precipitates after adsorbing SO2. The infrared spectra analysis and element analysis of the three types of precipitate showed that their chemical structures were basically the same. The structural formula is NH2(CH2)2NH(CH2)2NH3SO3NH2·2H2O; the product was determined to be a shaped crystal structure by XRD and SEM. In addition, the thermal stability analysis of the product revealed that the product sublimed at 123 °C and decomposed at about 185 °C.

IDENTIFIKASI SENYAWA KIMIA DAN AKTIVITAS ANTIBAKTERI EKSTRAK Piper Sp. ASAL PAPUA

The aim of this study was to identity the chemical compounds of the piper sp.Fruit originated from Papua, that has been used as “sirih pinang”(chew betle)and to determine the antibacterial activity of hexane and chloroform extraxt ofpiper sp. to Gram + bacteria isolates(Bacillus subtilis, Listeria monocytogenesdan Staphylococcus aureus) and Gram – bacteria isolates(Salmonellatyphimurium, Eschericia coli and Pseudomonas pseudomallei). The extractconcentration were 50 % and 25 %, and every treatment consisted of 3replications. The bacteriae growth media was Mueller Hinton Agar(MHA). Theresult of phytochemical screening of Piper sp.fruit(ether, alcohol,and waterextracts)showed that it contained esential oil, lipid,emodol,tannin,reducingsugar, anthrasenoid,polyuronide,glucocide,steroid glycoside.

VLE measurements of ether alcohol blends for investigation on reformulated gasoline

Separation processes in the chemical process industries is dependent on the science of chemical thermodynamics. In the field of chemical separation process engineering, phase equilibrium is a primary area of interest. This is due to separation processes such as distillation and extraction which involves the contacting of different phases for effective separation. The focal point of this research project is the measurement and modeling of binary vapour-liquid equilibrium (VLE) phase data of systems containing ether-alcohol organic compounds. The VLE data were measured with the use of the modified apparatus of Raal and Mühlbauer, (1998). The systems of interest for this research arose from an industrial demand for VLE data for systems containing ether-alcohol organic compounds. This gave rise to the experimental VLE data isotherms being measured for the following binary systems: a) Methyl tert-butyl ether (1) + 1-pentanol (2) at 317.15 and 327.15 K b) Methyl tert-butyl ether (1) + 2, 2, 4-trimethylpentane (2) at 307.15, 317.15 and 327.15K c) 2, 2, 4-Trimethylpentane (1) + 1-pentanol (2) at 350.15, 360.15 and 370.15K d) Diisopropyl ether (1) + 2,2,4-trimethylpentane (2) at 320.15, 330.15 and 340.15K e) Diisopropyl ether (1) + 1-propanol (2) at 320.15, 330.15 and 340.15K f) Diisopropyl ether (1) + 2-butanol (2) at 320.15, 330.15 and 340.15K The data for all the measured binary systems investigated at these temperatures are currently not available in the open source literature found on the internet and in library text resources. The systems were not measured at the same temperatures because certain system isotherm temperatures correlate to a pressures above 1 bar. This pressure of 1 bar is the maximum operating pressure specification of the VLE apparatus used in this project. The experimental VLE data were correlated for model parameters for both the  and methods. For the method, the fugacity coefficients (vapour-phase non-idealities) were tabulated using the virial equation of state and the Hayden-O’Connell correlation (1975); chemical theory and the Nothnagel et al. (1973) correlation method. The activity coefficients (liquid phase non-idealities) were calculated using three local-composition based activity coefficients models: the Wilson (1964) model, the NRTL model (Renon and Prausnitz, 1968); and the UNIQUAC model (Abrams and Prausnitz, 1975). Regarding the direct method, the Soave-Redlich-Kwong (Redlich and Kwong, 1949) and Peng-Robinson (1976) equations of state ii were used with the temperature dependent alpha-function (α) of Mathias and Copeman (1983) with the Wong-Sandler (1992) mixing rule. Thermodynamic consistency testing, which presents an indication of the quality and reliability of the data, was also performed for all the experimental VLE data. All the systems measured showed good thermodynamic consistency for the point test of Van Ness et al. (1973) - the consistency test of choice for this research. This however, was based on the model chosen for the data regression of a particular system. Therefore, the combined method of VLE reduction produced the most favourable results for the NRTL and Wilson models.

Competition of Ester, Amide, Ether, Carbonate, Alcohol and Epoxide Ligands in the Dirhodium Experiment (Chiral Discrimination by NMR Spectroscopy) [1]

Thirty-eight derivatives of 3-hydroxy-2-methylpropanoic acid, each with two different oxygen functionalities, were synthesized and subjected to the standard dirhodium experiment (1H NMR in the presence of an equimolar amount of the chiral dirhodium tetracarboxylate complex Rh*). Their structures represent ester, amide, carbonate, ether, alcohol and/or epoxy groups. Significant selectivity in the binding of those oxygen groups to the complex were determined. From these results, a priority list in binding to a rhodium atom of Rh* was established: epoxides > primary alcohols > ethers ≥ esters ≥ amides > carbonates > tertiary alcohols This sequence allows the prediction of the preferred binding site of oxygen-containing groups in polyfunctional compounds, which frequently occur among natural products, and, particularly, in asymmetric synthesis of such compounds. Differentiation of the enantiomers by the dirhodium experiment is easily accomplished due to numerous signal dispersions in nearly all cases.