Catalyst and treatment method for upgrading tar by using catalyst

The invention relates to a catalyst and a method for treating tar by using the catalyst. The catalyst is an alkali metal salt loaded catalyst and is prepared through the following steps: dropwise adding an alkali metal salt solution on a carrier particle to uniformly soak the particle by the solution, drying and roasting the particle, and cooling the roasted particle to obtain the alkali metal salt loaded catalyst. The method for treating the tar comprises the following steps: mixing the tar and small molecule alcohol, carrying out high-temperature gas-phase catalytic conversion treatment, and subjecting the creosote ingredient in the tar and the small molecule alcohol to etherification reaction by using the catalyst provided by the invention to convert the creosote in the tar to aromatic ether. The method is conductive to the increase of the caloricity and oil phase solubility of the tar and the reduction of the acidity and corrosivity of the tar. The catalyst preparation technology and tar treatment technology provided by the invention are simple and efficient, the raw material cost and the running cost are low, and the industrialized production is easily achieved. The raw materials and technological processes for the catalyst preparation and tar treatment are pollution-free and environment-friendly.