Related Experiment Video
Updated: May 14, 2026

Simultaneous Multi-surface Anodizations and Stair-like Reverse Biases Detachment of Anodic Aluminum Oxides in Sulfuric and Oxalic Acid Electrolyte
Published on: October 5, 2017
Decolourization of melanoidins by a electrocoagulation process using aluminium electrodes
1Gebze Institute of Technology, Department of Environmental Engineering, Cayirova, Gebze, Kocaeli, Turkey. kobya@gyte.edu.tr
Abstract:
The decolourization ofmelanoidins was studied with a batch electrocoagulation (EC) process using aluminium electrodes. The effects of conductivity (K = 500-3000 microS/cm), initial pHi (4.2-8.2), current density (j = 2.5-7.5 A/m2), initial melanoidin concentration (C0 = 100-800 mg/L) and operating time (tEC = 0-60 min) were investigated on the decolourization efficiency. The results obtained from the EC process were extremely efficient and able to achieve a decolourization efficiency of > 98% at pHi = 4.2, j = 5 A/m2, K = 2500 microS/cm, C0 = 100 mg/L and tEC = 10 min. The decolourization performance was dependent on pHi value since the lower pH values led to faster reactions and higher decolourization efficiency. Melanoidins in the EC process were removed by precipitation and charge neutralization at pH < 6.5, and both adsorption and sweep coagulation by amorphous Al(OH)3(s) occurred at pH > 6.5. The operating cost was calculated as 0.0096 Euro/m3
Related Concept Videos
Coagulation
Electrodeposition
Electrodeposition can...
Effects of EDTA on End-Point Detection Methods
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a result, EDTA...
Extraction: Advanced Methods
Masking and Demasking Agents
There are many masking agents, such as cyanide, fluoride, triethanolamine, thiourea, and 2,3-bis(sulfanyl)propan-1-ol (formerly 2,3-dimercapto-1-propanol), with the masking agent chosen based on the metal...
Colloidal precipitates
