Síntese das membranas inorgânicas (ZSM-5/y-alumina, MCM-41/y-alumina e compósito MFI-MCM-41/y-alumina) destinadas à separação emulsão óleo/água.

Abstract

The technology of synthesis of molecular sieve and inorganic membranes used were objects of study developed at the Laboratory for Developing New Materials (LABNOV) in recent years. The innovation of this study is given in the synthesis of the composite ZSM-5, MCM- 41, and incorporation of the same y-alumina inorganic membrane for separation of oil / water emulsion. This study aimed to: prepare materials (ZSM-5, MCM-41) via hydrothermal synthesis, composite (ZSM-5/MCM-41 and silicalite/MCM-41) via formation of mesoporosity on the crystals of zeolite ZSM-5. y-alumina by the decomposition of aluminum sulfate and subsequent conformation/compression to obtain the y-alumina ceramic membranes, inorganic membranes (composite ZSM-5-MCM-41 /y-alumina) via mechanical mixing. The products were characterized by X-ray diffraction (XRD), spectrophotometry energy dispersive X-ray (EDX), scanning electron microscopy (SEM) and N 2 adsorption (BET method). Besides the preparation and characterization, second membranes were evaluated in the removal of a synthetic oil process wastewater using a membrane separation column. Assays were performed under conditions of initial oil concentration 500 mg/L, equal to 25 ° C, atmospheric pressure, which allowed to observe the change in concentration of the permeate (mg/L) and the rejection coefficient (R%) temperature. A wash subsequent re-use in the separation system oil / water emulsion was carried out for each individual and membrane. The characterization results obtained showed that the molecular sieve MCM-41 and zeolite ZSM-5 were successfully obtained. We developed a composite material consisting of a ZSM-5 and zeolite molecular sieve MCM-41. XRD analysis confirmed the formation of this composite, but with this impurity identified as quartz. To eliminate the contamination was performed with a new synthesis of change in the chemical composition of zeolite ZSM-5 seeds gel and was succeeded to the non-contamination of the sample with respect to the phase quartz. The result obtained by XRD ceramic membrane (y-alumina) showed the presence of peaks characteristic of aluminum oxide (AI2O3). From tests for the separation of oil / water emulsion, it can be concluded that the insertion of the material (ZSM-5, MCM-41 and MCM-41, silicalite) to the ceramic membrane y-alumina improved process of separating oil emulsion / water. Among the three membranes, the MCM-41 /y-alumina showed the worst performance in the separation of the emulsion, the poor performance was attributed to the pore size of the structure. Oil as a general conclusion, the membranes (ZSM-5/y-alumina,MCM-41/y-alumina and silicalite-MCM-41/y-alumina) used for column separation membranes are very promising in the separation process emulsion oil/water.