## 1 Introduction
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**Name of the Process** & **Characteristics of** & **Characteristics of** & **Process Parameters** & **Parameters** & **IME Efficiency** & **Bibliography** \\  & **LL** & **Microelectrodes** & & & **Optimal** & \\ \hline  & & pH 6.4, & & pH 1.0; 3.0; 5.0; 7.0, & Cast-iron dosage & & \\ Microelectrolysis & N\({}_{\rm NH4}\) 1300 mg/L, & Cast iron & Fe\({}^{0}\) 25; 50; 75 and & 75 g/L & COD removal & \\  & CaCO\({}_{3}\) alkalinity & degreased 20 min & 100 g/L, & H\({}_{2}\)O\({}_{2}\): 97.0, 195.6, & after IME 38.2\%, & \\  & 10,400 mg/L, & in ethanol. & H\({}_{2}\)O\({}_{2}\): 97.0, 195.6, & mM90 min & IME + & after IME /H\({}_{2}\)O\({}_{2}\) \\  & COD 8546 mg O\({}_{2}\)/L & & 324.9, 538.8 mM. & 105 min & 65.1\% & \\ \hline  & & & Preliminary tests: & & COD removal \\  & & Scrap cast iron & pH 3; 5.7; 7.8, & SIME reactor: & 73.7\% in the \\  & & with an area of & Fe/C mass & & & combined process \\  & COD 538 mgO\({}_{2}\)/L, & 0.3–0.4 m\({}^{2}\)g\({}^{-1}\), & ratio\({}^{1}\)/3, 2/3/3; & 1/1, & & (without aeration \\  & BOD\({}_{3}\) 38 mgO\({}_{2}\)/L, & & 4/3; 5/3; 6/3; & Air flow rate & 60 min and with \\  & BOD\({}_{5}\)/COD 0.07, & & SIME reactor: & 80 L/h, & & \\  & pH 7.2 & & in 0.1M HCl & Air flow rate: 20; 40; & & \\  & & GAC. & 80; 120 L/h, & 100 mg/L & 86.1\% in a SIME & \\  & & & H\({}_{2}\)O\({}_{2}\): 0; 50; 100; & reactor with & \\  & & & 150; 200; 250 mg/L & & H\({}_{2}\)O\({}_{2}\) addition & \\ \hline  & & & & & Removal: \\  & Coupled & Concentrate LL & Medium-sized & Fe/GAC 3.0. & & COD 79.2\% \\ coagulation and & after the NF process: & scrap cast iron & Air flow rate: & pH 4, & OWO 79.9\% \\ aerated & pH 7.48, & 2 mm, washed in & 200 L/h. & H\({}_{3}\)O\({}_{2}\): 0.75 mM & Color 90.8\% \\ micro-electrolysis & COD 6500 mgO\({}_{2}\)/L, & 20% NaOH/H & H\({}_{2}\)O\({}_{2}\) (30\%), 0.2, & HRT; 2 h in IME & \\  & COD 5200 mgO\({}_{2}\)/L, & re-rinsed H\({}_{3}\)SO\({}_{4}\); & 0.50.75. 1.0. 1.25; & reactor with & \\  & & GAC rinsed in & 1.88; 2.5 mM. & aeration & Increase in the \\  & & GD\({}_{5}\)/COD ratio & distilled water. & pH 2; 3; 4; 5; 6; 7. & & BOD\({}_{5}\)/COD ratio \\ \hline  & & pH 8.5 \(\pm\) 0.1, & & & & \\  & Color: 500 \(\pm\) 50, & & & & & \\  & COD 3318.2 \(\pm\) & & & & & \\  & 2055 mgO\({}_{2}\)/L, & & 1/2; & pH 2.0; & Removal: & \\ Microelectrolysis & 2005, 397.5 \(\pm\) & Information not & GAC: 1, 5, 10 g/L, & GAC 10 g/L; & COD 85\% & \\  & 48.5 mgO\({}_{2}\)/L, & & pH: 2; 3, 4. & Fe\({}^{0}\)/GAC 2/1; & Increase in ratio & \\  & TOC 843.4 \(\pm\) & & Time: 30, 60 and & Time 90 min & BOD\({}_{5}\)/COD 0.31 & \\  & 71.5 mg/L, & & 90 min. & & & \\  & BOD\({}_{5}\)/COD 0.12 & & & & & \\ \hline  & & & Commercial iron & & & \\  & Leachate after the & dust-washed in & & & & \\  & biological treatment & 0.1 M HCl and & & & \\  & process: & washed 10 times & & & & \\  & pH 7.5-8, & in distilled water; & pH 3, 5, 6, & pH 3, & Removal: & \\  & thermal & COD 237.3– & & Activated & Fe/AC: 12/4 g/L & \\ micro-electrolysis & 262.6 mgO\({}_{2}\)/L, & 10 times in & Time: 5, 10, 20, & & & \\ micro-electrolysis & NO\({}_{3}\)-N 69.19–71.8, & distilled water. & 40 min. & Time: 20 min & TXN 54\% & \\  & NO\({}_{2}\)-N 2.38–2, & & Both & & & \\  & N\({}_{\rm NH4}\)-N & microelectrodes & & & & \\  & 217.9–234.0 mg/L & with a size of M. & & & \\  & & & 100 mesh. & & \\ \hline  & & & Cast-iron filings & Preliminary tests: & & \\  & & with an area of & pH: 2; 3; 4, & & \\  & & 0.3–0.4 m\({}^{2}\)g, & H\({}_{2}\)O\({}_{2}\): 10. 12; & & & \\  & pH 7.52, & defated in & 14 mL/L, & Fe-C: 55.72\% & & \\ Microelectrolysis– & COD 4980 mgO\({}_{2}\)/L, & ethanol and & Fe/GAC: 44; 52; 60 & H\({}_{2}\)O\({}_{2}\) 12.32 mL/L & Removal: & \\  & BOD\({}_{5}\) 548 mgO\({}_{2}\)/L, & washed out in & g/L, in a ratio of 3:1. & & \\  & BOD\({}_{5}\)/COD 0.11, & 0.1M H\({}_{2}\)SO\({}_{4}\) and & Time: 60 min. & & \\  & N\({}_{\rm NH4}\) 1850 mg/L & in water, & Column & Time 60 min & \\  & & GAC with a & experiment-LL flow & & \\  & diameter of & rate: 1.0; 1.5; 2.0; 3.0; & & & \\  & & 2–4 mm. & 6.0 mL/min. & & \\ \hline \hline \end{tabular}
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