Alexandria Engineering Journal (Dec 2020)
Parametric investigation of indigenous Nigeria mineral clay (Kaolin and Bentonite) as a filler in the Fluid Catalytic Cracking Unit (FCCU) of a petroleum refinery
Abstract
The operational effectiveness of a fluid catalytic cracking unit largely depends on its catalyst, which is a mixture of zeolite, binder, matrix and filler. The filler plays an active role as it provides the catalyst with physical strength and integrity and also presents a heat exchange platform where more imperative and costly zeolite component can be incorporated. In Nigeria, foreign kaolin clay is used as fillers because it contains lesser impurities when compared to the one indigenous to the country. In contrast, Nigeria bentonite clay have unique properties that can be processed and used as an alternative. This paper evaluates the suitability of kaolin and sodium bentonite from southern Nigeria as fillers in the Fluid Catalytic Cracking Unit. Initial characterisation with the aid of an XRF analysis confirmed the presence of iron oxide impurity on both the local and foreign crude clay (Bavaria, Germany). Wet beneficiation processes were carried out on all clay samples with different reaction times, temperatures and amounts of reagents to reduce impurities. Reaction time at 8 h proved more effective as 77% of iron oxide were removed from both the local and foreign clays. The product properties of the beneficiated samples also revealed iron oxide impurities that reduce impurities from 5.62% to 1.41% for kaolin clay and from 9.84% to 2.77% for bentonite clay. Samples of crude oil and products were tested to determine their physical properties using an Emmetteller Brunauer, a scanning electron microscope, a viscometer, and a pH meter to reveal the impact of the benefits on compliance with API standards. Aside from the increase or decrease of particulate or grain size, the structural modifications reflect the impact of mineral clay in retaining exchangeable cations (nutrients).
