FIELD: chemistry.
SUBSTANCE: invention relates to improvement of the method of producing (meth)acrylic acid or (meth)acrolein through gas-phase catalytic oxidation of at least one oxidisable substance, chosen from propylene, propane, isobutylene and (meth)acrolein, molecular oxygen or a gas, which contains molecular oxygen, using a multitubular reactor, with such a structure that, there are several reaction tubes, with one (or several) catalytic layer (catalytic layers) in the direction of the axis of the tube, and a coolant can flow outside the said reaction tubes so as to regulate temperature of reaction, in which temperature of the said reaction of gas-phase catalytic oxidation is increased by varying temperature of the coolant at the inlet for regulating temperature of the reaction, while (1) temperature of coolant at the inlet for regulating temperature of the reaction is varied by not more than 2°C for each variation as such, and (2) when variation is done continuously, the time interval from the variation operation, directly preceding the present, is not more than 10 minutes, and, in addition, the difference between the maximum value of peak temperature of reaction of the catalyst layer of the reaction tube and temperature of the coolant at the inlet for regulating temperature of reaction is not less than 20°C.
EFFECT: method in which sharp increase of temperature is suppressed even after changing reaction conditions with aim of increasing temperature for improving efficiency, thus preventing catalyst deactivation, and achieving stable output.
3 cl, 5 dwg, 5 ex
