| The vapor-liquid equilibrium for products of turpentine hydrogenation i.e. pinane- -pinene-longifolene system was investigated by using experimental method with vapor-liquid alternative circulation and data processing method of simplex-search, and the mathematic model for rectification has been built. Theoretic fundament and basic data for development of rectification and separation of hydrogenated turpentine system were provided in this paper. This paper covers the contents as follows:The experimental raw material pinane was prepared by catalytic hydrogenation of a -pinene at temperature 353-433 K, pressure 3.0-7.0 MPa, using Raney-nickel as catalyst and a -pinene as raw material, and qualitative and quantitative analysis for the products of hydrogenation was carried out by GC-MS method, the results shown that concentration of pinane was up to 99.7%.The hydrogenated turpentine was analyzed by gas chromatograph, using BP 5 boned phase, fused silica capillary column (30m 0.32mm 0.25 m), and the gas Chromatography conditions have been considered, the temperature program was as follows: 338K for o min, then 1K-min-1 to 363K, and finally 20K-min-1 to 423K, holding for 5 min. Nitrogen was used as gas carrier, the pressure before column was 0.07MPa, and the flow rate of carrier gas was 45mL-min-1. The flow rate of air was 300 mL-min-1; the flow rate of hydrogen was 30 mL-min-1; split flow ratio was set at 50:1; the flow rate of tail gas was 24 mL-min-1; The temperature of injector and detector was 523K. sample introdution was 0.2 L. The identity of the components was established by comparison of their GC-MS fragmentation patterns with those authentic samples, the results shown that the main components of hydrogenated turpentine were as follows: -pinene, cis-pinane, trans-pinane and longifolene.The vapor-liquid equilibria of high concentration pinane system in the temperature range of 421.23K~441.06K and high concentration longilofene system in the temperature range of 501.19-527.55K were determined respectively at pressure ranged from 59.34 kPa to 100.58kPa by using the modified Ellis still and capillary tube gas chromatograph analysis method. Based on the regulation that the solvent in dilute solution according with Raoult's law, the saturated vapor pressures of pinane, c/s-pinane and longifolene at experimental temperatures were calculated by Raoult's law, respectively, and their Antoine parameters(A,B,C) have been attained by regression, so that the correlations between saturated vapor pressure and temperature for pinane, c/s-pinane and longifolene weredescribed as follows: pinane(l), In(P1S/0.000133)= 9.299577- , A,=9.299577,B1=325.7533, C1=-319.4974 ; cis-pinane(2), In(P2S / 0.000133)= 9.271801 - ,A2=9.271801, B2=321.8889, C2=-319.400; longifolene(3),ln(P3S/0.000133)= 5.97818- , A3=5.97818, B3=3.69460, C3=-533.714, and the relativeerror was around 0.046~0.18%, and the saturated vapor pressure of pinane calculated was compared with value estimated by corresponding state group contribution method.The vapor-liquid equilibrium data for three binary systems of pinane- a -pinene, a -pinene-longifolene and pinane-longifolene and one ternary system of pinane- a -pinene-longifolene were determined at 0.1013MPa by the modified Ellis still. The thermodynamic consistency test indicated that the experimental data of three binary systems were reliable. The data were correlated by Wilson and NRTL equation, and the energy parameters have been obtained as follows: Wilson equation, -pinene(1)-pinane(2) system, g12 -g11 =2426.112 , g21-g11 =-1740.312 ; -pinene(1)-longifolene(2)system, g12 -g11 =2397.481 , g21-g11 =-2931.211 ;pinane(1)-longifolene(2) system,g12 -g11 =3806.733 , g21 -g11 =-3935.258 , NRTL equation, -pinene(1)-pinane(2) system, g12 -g11 =-2129.999 , g21 -g11 =2644.614 ; -pinene( 1 )-longif...
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