Catalyst for synthesizing methyl formate by virtue of gas-phase methanol carbonylation as well as preparation method and application of catalyst

The invention discloses a supported nano platinum group metal heterogeneous catalyst for synthesizing methyl formate by virtue of gas-phase methanol carbonylation. The supported nano platinum group metal heterogeneous catalyst is prepared from the following components accounting for the mass of a carrier: 0.01-2 percent of platinum group metal active component, and smaller than or equal to 20% of an optional additive. The invention also discloses a preparation method of the supported nano platinum group metal heterogeneous catalyst for synthesizing the methyl formate by virtue of the gas-phase methanol carbonylation. The preparation method comprises the following steps: optionally immersing the carrier into an aqueous or ethanol solution of an additive precursor, standing, drying, and roasting; then immersing the carrier into an aqueous or ethanol solution of a platinum group metal precursor, and uniformly mixing to enable the carrier to be uniformly dispersed in the platinum group metal precursor solution; carrying out ultrasonic waves treatment under the heating condition until a solvent of the solution volatilizes to be dry, and enabling the platinum group metal precursor to be uniformly adsorbed on the surface of the carrier; drying and roasting an obtained adsorbed sample; then adding a reducing agent, a structure-directing agent and a protective agent to carry out reduction reaction; and then carrying out filtering, washing and vacuum drying to obtain the supported nano platinum group metal heterogeneous catalyst.