Studies On Manufacturing Of Phthalonitrile By Ammoxidation Of O-Xylene

Abstract

Phthalonitrile is an organic compound with the formula C6H4(CN)2. It is a crystalline powder having a faint grayish yellow color and a slightly aromatic odor, similar to benzonitrile. Phthalonitrile is widely used as raw material for production of phthalocynine pigments. In India production of copper phthalocyanine pigments is mostly concentrated in Gujarat. The current manufacturing procedure is mixing phthalic anhydrid and urea which is giving environmental issues like generation of ammoniacal nitrogen in the effluent so it was thought of to make copper phthalocyanine pigment using Phthalonitrile as starting material. In a single stage continuous process it is possible to manufacture phthalonitrile by gas phase ammoxidation of o-xylene.Work carried out here is mostly concentrated to prepare suitable catalyst for ammoxidation of o-xylene to phthalonitrile. Vanadium oxide and vanadium phosphorus oxide(VPO) based catalyst are widely used for ammoxidation reaction. Efforts were also made to find out the non vanadium based catalyst for same reaction. Reaction mechanism of ammoxidation of o-xylene and factors affecting the ammoxidation reaction are also studied. Here four catalyst,vanadium oxide, Vanadium pyrophosphate (VPP), VPP/ZSM-5 and VPP/SiO2 were prepared and tested for ammoxidation of o-xylene to phthalonitrile on fixed bed reactor. However no singnificant results were obtained for any of four catalysts used here, only once trace amount of phthalonitrile was obtain in the ammoxidation runs of VPO/SiO2 catalysts. As result obtain here are not good enough for commercial application, however this research provides insight into complicity of the reaction this Process requires further reseach work to be carried out.