Improvement of hydrogen solubility and entrainment in hydrocracker feedstocks. Final technical report

Abstract

However, any opinions, findings, conclusions or recommendations DE-FG22-92MT92020.expressed herein are those of the author and do not necessarily reflect the views of DOE.The work on thermodynamic model for hydrogen solubility i n hydrocarbons and in hydrocracker feedstocks was performed by the graduate student Mr. Junjie Luo, and the gas solubility apparatus to measure solubility of hydrogen in hydrocarbons . ABSTRACTThe work on this project was initiated on September 1, 1992. The project consisted of two tasks: 1. Development of a thermodynamic model for hydrogen solubility in hydrocarbons and extension of this model to predict solubility of hydrogen in hydrocracker feedstocks at conditions similar to those of hydrocracking operations, and 2. Design and construction of a gas solubility apparatus to measure solubility of hydrogen in hydrocarbons and in hydrocracker feedstocks.The theoretical work proposed was fully accomplished by developing a sophisticated model for hydrogen solubility in hydrocarbons and in hydrocracker feedstocks at advanced temperatures and pressures. Two papers on this work have been submitted to the Journal, Industrial and Engineering Chemistry Research. Reviews of these articles are likely to be available shortly.The proposed experimental work ran into a number of obstacles, especially to get the original and newly designed on-line sampling technique to h c t i o n properly. A number of calibrations and tests for reproducibility were necessary to assure the accuracy of measured data. Although a very well designed gas solubility apparatus was built, not much tim&was left to generate sigmficant hydrogen solubility data. The p h are to use the apparatus in fbture to measure hydrogen solubility r data in liquid fuels to facilitate more efficient design of fie1 conversion systems. .. . PROJECT OBJECTIVES AND SCOPEThe objective of this project is to determine the conditions for the hydrogen-heavy oil feed preparation so as to optimize the yield of hydrocracking reactions. Proper contacting of hydrogen with heavy oil on the catalyst bed is necessary to improve the yields of the hydrocracking reactions.It is most desirable to have the necessary amount of hydrogen available either in the dissolved or in entrained state, so that hydrogen diffusion to the reaction site does not provide rate controlling resistance to the overd rates of hydrocracking reactions. This project proposes to measure solubility and entrainment data for hydrogen in heavy oils at conditions such as i n hydrocrackers, and investigate the improvement of these properties by usage of appropriate additives. Specifically, measurements will be canid out at temperatures up to 300 C and pressures up to 120 atmospheres.Correlations for solubility and entrainment kinetics will be developed fkom the measured data, and a method for estimating the yield of hydrocracking reactions using these correlations will be suggested. Exxon Research and Engineering Company will serve as private sector collaborator providing A&T w i t h test samples ...

A method to predict solubility of hydrogen in hydrocarbons and their mixtures

“…Hydrogen solubility (in terms of mole fraction) also increases with hydrocarbon carbon number as shown by experimental measurements (Lal et al, 1999;Park et al, 1995;Cai et al, 2001;Florusse et al, 2003). Most predictive methods for estimation of solubility of hydrogen in petroleum mixtures are similar to those used for solubility of other gases such as CO 2 and methane and are based on use of equations of states as discussed by Kabadi (1997) and Schwarz and Prausnitz (1987).…”