Patent ID: 9739736
Date: 2017-08-22
CPC Classifications: B01J,C07C,C10G,G01N

Claim:
1. In a method of determining the HF acid strength of the HF acid in an HF olefin/iso-paraffin alkylation unit having a settling vessel in which a hydrocarbon phase comprising alkylate and an HF acid phase containing acid soluble oil (ASO) and water are separated into a hydrocarbon phase and a denser HF acid phase with an interface between the two phases, the method comprising determining the density of the HF acid phase from the density profile of the hydrocarbon and HF acid phases in the settling vessel and from the density of the HF acid phase determining the proportion of water and ASO in the HF acid phase to determine the HF acid strength; wherein the HF acid strength is determined from measurements of the density of the HF acid phase, of the temperature and the proportion of water in the acid phase and the HF acid strength is determined from the measured density, temperature and water proportion of the HF acid phase according to the relationship: where c