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Figure1. The process of carrier preparation. 2.3. Experimental Procedure
At a temperature of 25 ◦ C, the experiment was carried out by adding 500 mL of actual wastewater to a 1000 mL beaker. The raw material for the ozone generators was oxygen. The ozone generator was preheated for 10 min while the ozone flow rate was adjusted using the flowmeter. The catalyst was then added at the start of the reaction. Following the reaction, the supernatant was collected for analysis. 2.4. Analysis Methods HJ 828-2017, “Water quality—determination of the chemical oxygen demand—dichromate method” was used to calculate COD. HJ 535-2009, “Water quality—determination of am- monia nitrogen reagent—Nessler’s spectrophotometry,” was used to determine ammo- nia nitrogen. HJ 670-2013, “Water quality—determination of orthophosphate and total phosphorus—continuous flow analysis (CFA) and ammonium molybdate spectrophotome- try,” was used to calculate total phosphorus. In addition, the determination of total nitro- gen was based on GB11894-89 “Water quality—determination of total nitrogen—alkaline potassium persulfate digestion UV spectrophotometric method”. The suspended solids were determined according to GB11901-89, “Water quality—determination of suspended substance—gravimetric method”. The pH value was calculated using the GB/T 6920-1986 glass electrode method. The above test methods were developed by the Chinese gov- ernment as national or industrial standards. On each sample, three repeated tests were performed, and the results were reported with an average value of less than 5%. The wastewater functional group changes were investigated using Fourier transform infrared (FT-IR). To prepare the sample, 300 mL was filtered through a 0.45 μ m membrane, concentrated to 15 mL by rotary evaporation of the solvent at 50 ◦ C, and freeze-dried to obtain a solid powder. For FT-IR detection, the product was combined with a potassium bromide tablet. The scanning wavelength was set to 400–4000 cm − 1 , the resolution was set to 4 cm − 1 , and the scanning number was set to 32 [18]. Gas chromatography–mass spectrometry (GC-MS) is an accurate analytical tool for determining water quality and organic matter. The following are the specific steps: a total of 100 mL of wastewater was filtered through a 0.45 μ m microporous membrane before being transferred to a partition funnel. Following that, 10 g sodium chloride was added and shaken to dissolve. Then,
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