Vol. 3, Issue 5 (2016)
Treatment of drilling mud waste water of block six oilfield plant Sudan using zeolites
Author(s): Sahl, I.Bkhit Yasin, Elmugdad, A.A., Adil Elhag Ahmed
Abstract: Natural zeolite samples were collected from Gedaref state (East of Sudan) and characterized using XRF, FT-IR, XRD powder and N2-adsorption analysis. The elemental analysis by XRF showed the zeolite sample contains some impurities such as MgO, CaO and Fe2O3 with moderate to high percentages. FT-IR spectrum emphasized the existence of aluminosilicate core of the zeolite whereas, XRD powder indicates that zeolite of Stellerite-type was detected to dominate the natural sample. The natural zeolite material was activated with hydrochloric acid and sodium chloride solutions before applying for the heavy metals treatment process. The removal efficiency of the activated natural zeolite was studied using standard solution containing mixture of some heavy metals. Some parameters such as pH, concentration of metal ions and contact time for high removal efficiency were optimized using aqueous solution of Cr3+, Fe2+, Zn2+ and Co2+ionic mixture. The results showed that at optimum conditions, the zeolite material has consistence efficiency to remove all heavy metals in the mixture i.e. ca. 77%. Then these optimum conditions were followed to minimize the level of targeted heavy metals (i.e. Cr3+, Fe2+, Zn2+ and Co2+) in the wastewater of drilling mud (fluid). The experimental data showed that the respective removal percentages of these heavy species were 96.8%, 83.8%, 38.4% and 38.3% the mechanism by which the zeolite removed these metallic species was investigated using Freundlich and Langmuir models. The findings illustrated that the removal of Cr3+ and Fe2+ ions fitted well to Freundlich isotherm (model), whereas that of Co2+ and Zn2+ was found to obey Langmuir model.