Study On The Effect Of Ammonium Molybdate Catalyst On The Synthesis Of Copper Phthalocyanine

Copper phthalocyanine is a blue pigment with superior performance.Since it was produced and commercialized as a pigment in the 1930s,it has been occupying an important position in the pigment industry and is the most important in the coating,paint and printing ink industries.Commonly used blue organic pigments.At present,the phthalic anhydride-urea method is the most widely used method for producing copper phthalocyanine at home and abroad,and the ammonium molybdate catalyst is the most important raw material in this method.Because the synthesis mechanism of copper phthalocyanine by the phthalic anhydride-urea method is more complicated and the synthesis reaction process is longer,more side reactions will occur during the reaction process.These side reactions are mainly related to urea,which will cause the loss of urea,while ammonium molybdate The catalytic mechanism of urea is to catalyze the decomposition of urea into ammonia gas and isocyanic acid to participate in the synthesis reaction of copper phthalocyanine,which is closely related to the consumption of urea.Therefore,it is necessary to understand the influence of ammonium molybdate catalyst on the synthesis reaction of copper phthalocyanine.On the one hand,it can reduce the feeding of ammonium molybdate within an appropriate range,and on the other hand,it can effectively utilize urea and increase the yield.Ammonium dimolybdate,ammonium tetramolybdate,and ammonium heptamolybdate are three common products of ammonium molybdate,which can all be used as catalysts.In this paper,the possibility and applicability of three kinds of ammonium molybdates as urea-phthalic anhydride method for the synthesis of copper phthalocyanine are firstly investigated,and the three kinds of ammonium molybdates have their respective effects on the yield of copper phthalocyanine and the quality of copper phthalocyanine products.It is found that ammonium heptamolybdate is most suitable as a catalyst for the synthesis of copper phthalocyanine.The highest yield is 88.1%,the highest yield of ammonium dimolybdate is 82.3%,and the highest yield of ammonium tetramolybdate is 83.4%.At the same time,the quality of copper phthalocyanine products of ammonium heptamolybdate is also good,which is mainly reflected in the lowest free copper content in copper phthalocyanine and the highest copper phthalocyanine content.At the same time,the changes in the yield of copper phthalocyanine,the acid boiling removal rate,and the content of free copper and copper phthalocyanine in copper phthalocyanine products were summarized as the amount of ammonium molybdate catalyst increased.Among them,the yield of copper phthalocyanine will first increase and then decrease with the increase in the amount of the catalyst.The reason why the yield decreases when the amount of the catalyst is too high is analyzed.The response has increased dramatically.Finally,through experiments,it was found that the color and morphology of the three copper phthalocyanine products catalyzed by ammonium molybdate were consistent,which was basically independent of the type of ammonium molybdate catalyst used.