Characterization of brines and evaporites of Lake Katwe, Uganda

Abstract

Lake Katwe brines and evaporites were investigated to determine their chemical, mineralogical and morphological composition. 30 brine samples and 3 solid salt samples (evaporites) were collected from different locations of the lake deposit. Several analytical techniques were used to determine the chemical composition of the samples including Inductively Coupled Plasma–Atomic Emission Spectrometry (ICP–AES), Inductively Coupled Plasma–Sector Field Mass Spectrometry (ICP–SFMS), ion chromatography, and potentiometric titration. The mineralogical composition and morphology of the evaporites was determined using X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Physical parameters of the lake brines such as density, electrical conductivity, pH, and salinity were also studied. The results show that the lake brines are highly alkaline and rich in Na+, Cl-, image, image, and image with lesser amounts of K+, Mg2+, Ca2+, Br-, and F- ions. The brines show an...