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Isophthalic acid (IPA) is an important aromatic compound, is widely used in organic synthesis, especially in the polyester industry. The traditional crafts Co-Mn-Br catalytic system, the MX conversion rate, IPA yield, but under conditions of high temperature corrosion of equipment caused by Br serious. Solve this problem, we developed a non-bromine catalyst system, using Co-Mn-PW12/AC catalyst, and greatly reduce the corrosion of the equipment under the high temperature conditions caused by Br. First, examine phosphotungstic acid (PW , 12 ) under homogeneous catalytic reaction temperature, pressure, and catalyst content, manganese, cobalt ratio, moisture content, air flow, and a stirring speed of the reaction process. The results showed that: (a) increasing the temperature, pressure, stirring speed, lower water content, can accelerate the reaction rate; (b) increase the PW 12 concentration of manganese drill ratio and air flow rate, the reaction rate to accelerate slow; (c) When the temperature as 215 ° C, for 3 MPa pressure, PW12 0.52% (wt), the cobalt ion is 0.088% (by weight) of manganese, cobalt ratio 2.46 / 1 (by weight) and a moisture content of 4%, air flow rate 1.2L/min, the rotational speed of 350rpm, the fastest reaction rate, isophthalic highest yield. Secondly, the effects of the PW 12 homogeneous catalytic reaction kinetics. Rung-Kutta method to calculate the kinetic parameters, the results show that: (a) the reaction temperature is a significant effect on the reaction rate, elevated temperature step-by-step reaction rate significantly accelerated; (b) from the PIA to 3-CBA activation energy (71.9636kj /. mol), the control of the main reaction step; the of MX to 3-IMA activation energy followed (69.0418kj/mol); 3-CBA to IPA activation energy (64.3108kj/mol); 3-IMA to the minimum activation energy of PIA 42.6311kj/mol; (c) the main reaction of MX ,3-IMA, PIA and 3-CBA reaction order close to 1, for 0.9713,1.0605,0.7914 and 1.1892, respectively; each step of the reaction of oxygen partial pressure level number is not 0, of 0.2148,0.5699,0.1929 and 0.466, respectively. Finally, the effects of activated carbon supported phosphotungstic acid (PW 12 / AC) the catalytic oxidation MX effect. In the usage of activated carbon for 4.5 g, the the PW 12 mass fraction of 13%, the activation temperature of 220 ° C, the best effect of the catalyst in the case of activation time of 4h. Heterogeneous catalysis under the same conditions, the MX conversion rate slightly higher than the homogeneous IPA yield is 13.1% higher than the homogeneous combustion decreased by 25.25% at the same time. As for how to further accelerate the reaction rate, to improve the yield of the target product needs to be further studied.
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