Surface deposited supported germanium-based or titanium-germanium-based catalyst and preparation method therefor and use thereof

A method for preparing a supported catalyst, the supported catalyst being a surface deposited supported titanium-germanium-based catalyst, wherein, the catalyst comprises a carrier, a supported deposition layer, and an active component, the carrier is an inorganic porous material modified and coated by a silicate ester, the supported deposition layer is located on the carrier and has a porous structure, and the active component is deposited on the supported deposition layer, and the preparation method comprises steps of:

• carrying out a precipitation reaction on a suspension of the carrier, a water-soluble calcium salt, a water-soluble aluminum salt, a water-soluble zirconium salt with a water-soluble hydroxide and an alkali, filtering, and calcining to form the supported deposition layer on the carrier;
• the alkali is selected from carbonates and/or bicarbonates;
• the specific surface area of the carrier containing the supported deposition layer is greater than the specific surface area of the carrier;
• dispersing the carrier containing the supported deposition layer in water to obtain a suspension of the carrier containing the supported deposition layer;
• carrying out a hydrolysis reaction on the suspension of the carrier containing the supported deposition layer with a germanium source and a titanium source to obtain a catalyst precursor;
• carrying out a reaction on the catalyst precursor with a silicate ester and water, and loading the active component on the supported deposition layer to obtain the surface deposited supported titanium-germanium-based catalyst;
• the water-soluble hydroxide is selected from one or two of sodium hydroxide and potassium hydroxide;
• the molar ratio of the water-soluble calcium salt, the water-soluble aluminum salt and the water-soluble zirconium salt for preparing the carrier containing the supported deposition layer is (0.5-2.5):(1.0-2.0):(0.8-3.5);
• in the surface deposited supported titanium-germanium-based catalyst, the mass ratio of the carrier, the supported deposition layer, and the effective germanium and the effective titanium in the active component is (78.1-89.4):(7.5-12.5):(2.5-7.5):(0.6-1.9), wherein the inorganic porous material is selected from nanoporous alumina, nanoporous alumina-zirconia, nanoporous silica, nanoporous barium sulfate, and combinations thereof, with a particle size of 20-80 nm and a specific surface area of 220-400 m2/g.

A method for synthesizing a PETG or PCTG polyester, wherein, the synthesis method comprises steps of:

• carrying out a precipitation reaction on a suspension of a carrier, a water-soluble calcium salt, a water-soluble aluminum salt, a water-soluble zirconium salt with a water-soluble hydroxide and an alkali, filtering, and heat treating to form a supported deposition layer on the carrier;
• the alkali is selected from carbonates and/or bicarbonates;
• the specific surface area of the carrier containing the supported deposition layer is greater than the specific surface area of the carrier;
• dispersing the carrier containing the supported deposition layer in water to obtain a suspension of the carrier containing the supported deposition layer;
• carrying out a hydrolysis reaction on the suspension of the carrier containing the supported deposition layer with a germanium source to obtain a catalyst precursor;
• carrying out a reaction on the catalyst precursor with a silicate ester and water, and loading the active component on the supported deposition layer to obtain a surface deposited supported germanium-based catalyst;
• the inorganic porous material is selected from nanoporous alumina, nanoporous alumina-zirconia, nanoporous silica, nanoporous barium sulfate, and combinations thereof, with a particle size of 20-80 nm and a specific surface area of 220-400 m2/g;
• using terephthalic acid, ethylene glycol, and 1,4-cyclohexanedimethanol as polymerization monomers to carry out esterification and polymerization reactions in the presence of a catalyst to obtain the PETG or PCTG, where the catalyst comprises the surface deposited supported germanium-based catalyst;
• the water-soluble hydroxide is selected from one or two of sodium hydroxide and potassium hydroxide;
• the molar ratio of the water-soluble calcium salt, the water-soluble aluminum salt and the water-soluble zirconium salt for preparing the carrier containing the supported deposition layer is (0.5-2.5):(1.0-2.0):(0.8-3.5);
• in the surface deposited supported germanium-based catalyst, the mass ratio of the carrier, the supported deposition layer and the effective germanium in the active component is (72.5-87.5):(7.5-12.5):(5.0-15.0);
• the catalyst comprises a carrier, a supported deposition layer, and an active component, the carrier is an inorganic porous material modified and coated by a silicate ester, the supported deposition layer is located on the carrier and has a porous structure, and the active component is deposited on the supported deposition layer.