Process – Effects on Ammonia, Chromium, Total Suspended Solid,

Overview

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Key numbers

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• 30 mins to removal efficiency of 60.7%, 32.9%, 72.8%, 53.4%, and 53.4% for NH3, Cr(III), TSS, BOD, and COD
• tems in eliminating a wide range of organic (11), are purchased from Merck (Germany). All analyti-
• 50 rpm, while the aerator was set with a flow of 3.5 100 mg/L maximum. These results underscore the
• 60.7% was achieved with the same voltage of
• search data presented in Table 1 highlights concern- with hydroxyl radicals to form Fe(OH)3, thereby
• nia is measured at 123.10 mg/L, surpassing the 10 cals to form NH2 and hydrogen. However, there
• mg/L threshold; chromium is at 0.58 mg/L, exceed- were some anomalies in the removal efficiency
• above the 200 mg/L standard; BOD is alarmingly rameter levels unexpectedly increased. Accord-
• high at 3923 mg/L compared to the 50 mg/L limit; ing to a previous study (25), this increase may be
• and COD stands at 11413 mg/L, far exceeding the due to the formation of ligands that initially bind
• Table 1. Characteristics of leather tannery wastewater
• Cr(III) (mg/L) 0.58 0.5 Exceeds the max. concentration
• process. The lowest removal efficiency is 37.6%
• charged state) act as Lewis’s acids, i.e. accept (and cy was 53.4% with 10V treatment and 120 mins
• or due to saturation of the catalyst that reacts Table 2 shows Available studies on tannery
• moval efficiency was 61.1% with 6 V treatment removal. The electrochemical oxidation process
• removal efficiency was 72.8% with 6 V treat- taining 32–81.2% (28, 29) with 90% color re-
• The lowest removal efficiency was 35.4% operating conditions, small equipment sizes, little
• time. Meanwhile, the highest removal efficien- Photochemical process using Fenton (31),
• cy was 53.4% with 8 V treatment and 60 min ZnO (32), bentonite-Zn (33), and BiVO4–ZnO
• detention time as shown in Figure 2d. Based (23), has variate COD removal of 83%, 97.7%,
• of efficiency reduction at different potential dif- ganic carbon (TOC) higher than 93% (32). The
• mins and slows down afterward. This can hap- nearly 100% (35). ZnO and TiO2 photocatalysts
• Table 2. Available studies on tannery wastewater treatment using oxidation methods
• Electrochemical oxidation COD: 3600 mg/L COD: 32% (28)
• BiVO4–ZnO photocatalytic process COD: 3000 mg/L COD: 64% (23)
• Bentonite-Zn photocatalytic process COD: 100 mg/L COD: 35.3% (33)
• Cr(VI): 30 mg/L Cr(VI): 95.4% (34)
• TiO2 Photo electrocatalytic oxidation Cr(VI): 14.12 mg/L Cr(VI): 100% (35)
• Electrochemical oxidation COD: 7189 mg/L COD 81.2% (29)
• Cr(III): 0.58 mg/L NH3: 60.7%
• Electro-Fenton oxidation TSS: 373.80 mg/L Cr(III): 32.9% This study
• of 95.4% and 88% respectively. In the realm of The electro-Fenton method on the waste
• traviolet (UV) absorption, ZnO has a good pho- 60.7%, 32.9%, 72.8%, 53.4%, and 53.4% of
• has significant COD and color removal of 70%

Methods (brief)

• mins was used to see changes in the sample. The results obtained are electro-Fenton method has an effective time of
• at an acidic pH below 4 (12). The reduction of Fe3+ Samples and chemicals
• an aqueous environment, from which the reaction A leather tannery wastewater sample was tak-
• nery effluent collected from tannery wastewater off. The drop in efficiency at 120 minutes is due
• the removal efficiency was still smaller com- to other oxidation process, sample used in this

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

• Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
• Baby Sunscreen, Mineral (ZnO + TiO2)
• Tin
• Chromium

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Update history

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