Preparation method of nitrogen-sulfur double-doped biochar material for degrading phenol in water

The invention discloses a preparation method of a nitrogen-sulfur double-doped biochar material for degrading phenol in water, which comprises the following steps: S1, cleaning waste fireworks with ultrapure water multiple times, and drying in a vacuum drying oven to obtain clean firework buds; s2, shredding, grinding and sieving the dried firework buds to obtain taupe firework powder, uniformly mixing the taupe firework powder with a certain amount of thiourea, and grinding by using a ball mill to obtain a mixture; and S3, calcining the mixture in a tubular furnace under the protection of inert gas, washing the calcined product with ultrapure water and ethanol, transferring the washed product into a vacuum drying oven, and drying to obtain the nitrogen-sulfur double-doped biochar material. The biochar material prepared by the method is of a porous structure, has a relatively large specific surface area, and is beneficial to adsorption of peroxymonosulfate on the surface of the material, so that target molecu