Flotation is a main technique for extraction of elements from ores with suitable grades, which is based on separating valuable particles from unwanted particles. Apatite with the formula of P2O5 can be extracted by flotation method. There are some gangue components in apatite. Hematite is one of the most important gunge minerals in phosphate ore. Fatty acids are the traditional collectors for apatite flotation but they have a poor selectivity against phosphate minerals. So, auxiliary reagents are needed. In this work, we formulated two collector packages with the same fatty acids and Nonylphenol ethoxylated (NPE) as anionic and nonionic surfactants but different in auxiliary reagents, and made a comparison between them in apatite flotation. Auxiliary reagents are polyethylene oxide (PEO) and paraffin. The results indicated that selectivity due to utilize PEO is better but for recovery, using paraffin is suitable. PEO can improve selectivity of the collector but paraffin can increase the collecting ability. تفاصيل المقالة

The Manganese complex of meso-tetrakis (4-carboxyphenyl) porphyrin was immobilized onto the surface of functionalized activated carbon and used as a heterogeneous catalyst for the oxidation of different alkenes. The heterogenized catalyst has been fully characterized using Ultraviolet–visible (UV-Vis), Fourier-transform infrared (FTIR), and atomic absorption spectroscopies as well as thermogravimetric analysis (TGA), scanning electron microscopy(SEM), and nitrogen adsorption-desorption (BET method) analyses. The Catalytic activity of the catalyst was investigated in the epoxidation of alkenes with H2O2 as a green oxidant. The influence of different parameters including time of reaction, molar ratio of catalyst, imidazole, and amount of oxidant on the efficiency of the catalyst was investigated.Complete conversion of the indene, α-methyl styrene, and 4-methyl styrene was achieved after 4 h at room temperature. تفاصيل المقالة