Removal of Cationic Dyes Utilizing Natural Coffee Pulp Coagulant
Correa Mahecha, Felipe
Cuesta Parra, Diana
Sandoval, Juan A.
Mayorga, Manuel A.
Ortiz, Samuel A.

How to Cite

Correa Mahecha F., Cuesta Parra D., Sandoval J.A., Mayorga M.A., Ortiz S.A., 2021, Removal of Cationic Dyes Utilizing Natural Coffee Pulp Coagulant, Chemical Engineering Transactions, 87, 487-492.


The color removal activity of polyphenolic extracts obtained by maceration of coffee pulp with the Coffea arabica species was evaluated in synthetic waters prepared with three commercial dyes: methylene blue, malachite green and crystal violet. The extract was prepared by maceration using milled coffee pulp in a hydroalcoholic solution with a volume ratio of 1:1 and a solid: solvent ratio of 1:20 (g: mL). Additionally, total polyphenols were quantified using the Folin-Ciocalteu method and pH effects were evaluated based on the color removal percentages at fixed doses of 2.5 mg GAE / L (gallic acid equivalent per liter). Maximum removals with the values of 61.74%, 91.65% and 86.47% were obtained for malachite green, crystal violet and methylene blue at a pH of 4.26, 8.40 and 9.22, respectively. The present study confirms the potential use of waste extracts from the coffee industry for the removal of cationic dyes by coagulation.
Keywords- Cationic coagulants, Polyphenols, coffee pulp.