Treatment of produced water from the Cuban petrochemical industry based on nature zeolite adsorption technology

Abstract

Produced water (PW) from the Cuban oil industry is a source of oil and chemicals into the sea. This kind of wastewater is a complex mixture of organic and inorganic compounds. The high salinity, metals and sediment could pose severe environmental impacts upon inadequate disposal. This study is based on the treatment proposal of this kind of wastewater used nature zeolite (N-Z) taking into account the deposits of this material across the island. Results suggest that, significant changes between a doses in terms of the adsorption of organic compounds were not found evaluated by UV-Vis at 295nm, the behavior was for the basic pH of the solution and the textural characteristics of the N-Z such as low surface area of 35 m2/g. Differents doses of N-Z vs. CL were studied, the best to carry out the adsorption process was 0,5 g of zeolite per 50mL of clear liquid (CL)according to the evaluation of the solid phase by ICP-OES(Inductively coupled plasma - optical emission spectrometry) the higher doses increase the compounds that are part of the zeolite structure. On the other hand the evaluation of the liquid phase with the Spectrophotometer at 295nm were no observed significant changes, demonstrating the non-adsorption of organic compounds. At the best doses the selectivity of the zeolite of heavy metal was Zn2+> Fe2+> Cu2+> Mn2+ and the ion exchange occurring by Al2O3 and CaO, also was evaluated by TGA (Thermogravimetry) analysis detecting a small difference in ash content between the virgin and exhausted zeolite that confirm the adsorption of inorganic compounds.