Reference

Separation of benzene and toluene from close boiling nonaromatics by extractive distillation

Separation of benzene and toluene from close boiling nonaromatics by extractive distillation. Berg, Lloyd (Montana State Univ., Bozeman, MT 59717, USA). AIChE J., 29(6), 961-6 (English) 1983. CODEN: AICEAC. ISSN: 0001-1541. 141-05-9 and 102-76-1 are cas registry numbers. These chemicals are also mentioned in this article. DOCUMENT TYPE: Journal CA Section: 45 (Industrial Organic Chemicals, Leather, Fats, and Waxes) Section cross-reference(s): 25, 48 C6H6 [71-43-2] and PhMe [108-88-3] were sepd. from nonarom. hydrocarbons with similar b.p., i.e. C6H6 from cyclohexane [110-82-7] or 2,4-dimethylpentane [108-08-7] and PhMe from methylcyclohexane [108-87-2], 2,4,4-trimethyl-1-pentene [107-39-1], or 2,2,4-trimethylpentane [540-84-1], by extractive distn. with mixts. of org. compds. boiling higher than C6H6 or PhMe. One of the most effective for C6H6 was a mixt. of phthalic anhydride (I) [85-44-9], maleic anhydride (II) [108-31-6], and adiponitrile [111-69-3]; or for PhMe, a mixt. of I, II, and triacetin [102-76-1]. Relative volatilities were detd. with >200 1-, 2-, or 3-component mixts. of 45 org. compds. .

Vibrational analysis of dimethylpentanes

Vibrational analysis of dimethylpentanes. Jaiswal, R. M. P.; Crowder, G. A. (Dep. Chem.Chemicals with cas numbers 565-59-3 and 108-08-7 also play role., West Texas State Univ., Canyon, TX 79016, USA). Can. J. Spectrosc., 28(5), 160-4 (English) 1983. CODEN: CJSPAI. ISSN: 0045-5105. DOCUMENT TYPE: Journal CA Section: 73 (Optical, Electron, and Mass Spectroscopy and Other Related Properties) Section cross-reference(s): 22 Vibrational spectra were obtained for 2,2-dimethylpentane, 3,3-dimethylpentane, 2,3-dimethylpentane, and 2,4-dimethylpentane (DMP), and were interpreted with the aid of normal coordinate calcns. 2,2-DMP and 2,4-DMP each exist in only 1 mol. conformation. 3,3-DMP exists in >1 conformation, but it crystallizes in the conformation with C2 symmetry. Eleven force consts. of a 32-parameter modified valence force field were refined to simultaneously fit 103 frequencies of 2,2-DMP, 2,4-DMP, and the C2 conformer of 3,3-DMP, with the av. difference between obsd. and calcd. values being 4.4 cm-1, or 0.48%. The resulting force consts. were used to calc. zero-order frequencies of the C1 and C2v conformers of 3,3-DMP and 5 possible conformers of 2,3-DMP. The C1 conformer of 3,3-DMP also exists in the liq., but the presence of the C2v conformer could not be confirmed. Comparison of obsd. and calcd. frequencies of 2,3-DMP shoed the probable presence of 4 conformers. .