Method for preparing methyl formate

A method for preparing methyl formate, comprising at least the steps of:

• a) introducing a raw material containing formaldehyde, methanol and/or dimethyl ether into a first reaction zone to come into contact with a catalyst A, so as to obtain a component I;
• b) introducing the component I obtained by separation in step a) into a second reaction zone to come into contact with a catalyst B, so as to obtain methyl formate as a product, dimethyl ether, and a component II by separation;
• and
• c) returning dimethyl ether obtained by separation in step b) to the first reaction zone, and returning the component II to the second reaction zone;
• wherein, in step a), the temperature is 50-100° C. in the first reaction zone;
• the ratio of formaldehyde, methanol and/or dimethyl ether in the raw material is formaldehyde:methanol and/or dimethyl ether=1:2-4 based on the mole number of carbon atoms contained in respective component;
• and the mass hourly space velocity of formaldehyde in the raw material is 0.01-15.0 h-1;
• in step b), the temperature is 50-200° C. and the pressure is 0.1-10 Mpa in the second reaction zone;
• and
• the components in the first reaction zone and the second reaction zone are each independently a gas phase and/or a liquid phase.