Treatment agent for petrochemical wastewater and preparation method of treatment agent

The invention discloses a treatment agent for petrochemical wastewater and a preparation method of the treatment agent. The treatment agent is prepared from the following raw materials in parts by weight: 2-10 parts of methyl isothiazolinone, 4-8 parts of sucrose, 6-12 parts of melamine, 10-16 parts of bentonite, 3-8 parts of mirabilite, 2-7 parts of aluminum sulfate, 2-5 parts of sodium silicate, 10-20 parts of lithopone, 5-12 parts of rhubarb, radix scutellariae and cortex phellodendri powder, 1.5-4 parts of a rhizoma coptidis liquid, 3-9 parts of caulis trachelospermi and 0.5-3 parts of gentiana apiata. The invention further discloses the preparation method of the treatment agent. The treatment agent has the advantages of wide raw material source, simple preparation process and low production cost, and is suitable for large-scale industrial production; the components of the treatment agent draw on strong points and make up for weak points mutually and play a synergistic role, the growth environment of bacteria is destroyed, the sterilization effect is enhanced, a good sterilization effect can be realized with only a small dose, the sterilization time is long, and the use effect is good.