The Study of the Sulphation of [alpha]-olefins

Abstract

The sulphation of hexadecene, in concentrated sulphuric acid (98% w/w), has been investigated in a votator scraped-surface heat exchanger reactor with "no-leak". The reactor flow pattern (tangential and axial) has been investigated and the theoretical tangential flow velocity profile determined when it was found that, at the annulus width d/3, the flow direction is always reversed and each side exhibits a parabolic velocity profile. Therefore, a model was developed which showed that the reactor consisted of two series of CS T.R. approximations in parallel having the volumes of (1/3 Vtotal ) and (2/3 Vtotal). The scaling-up of a pilot plant reactor for industrial purposes has been based on the power consumption, and a semi-empirical equation representing the power consumption has been derived from the experimental results. The conversion of hexadecene to the reaction products, namely monoalkyl sulphuric acid, dialkyl sulphate, and polymer, was examined at the different reaction parameters (the speed of rotation of the inner cylinder, residence time, and molar ratio of the reactants), and it was shown that, although the reactants are immiscible initially, the heterogeneous reactions become homogeneous in a very short time (less than a second). So that the reaction kinetics can be analysed by a homogeneous model, and the best conditions to achieve the highest yield were found experimentally.