Valorization of the Vicia faba mucilage on textile wastewater treatment as a bio-flocculant: process development and optimization using response surface methodology (RSM)

• Published in: Water science and technology 2017-02, Vol.75 (3-4), p.629-642
• Main Authors: Bouatay, Feriel, Eljebsi, Nesrine, Dridi-Dhaouadi, Sonia, Mhenni, Farouk
• Format: Article
• Language: English
• Subjects: Alum Compounds - chemistry; Aluminium; Aluminium sulfate; Aluminum; Aluminum sulfate; Analytical methods; Atoms & subatomic particles; Biological Oxygen Demand Analysis; Chemical oxygen demand; Coagulants; Coagulation; Decoloring; Decolorization; Denim; Dyes; Effluents; Flocculants; Flocculation; Industrial Waste - analysis; Infrared spectroscopy; Low cost; Membranes; Methods; Modelling; Models, Theoretical; Mucilage; Mucilages; Natural products; Optimization; Oxygen demand; Plant Mucilage - chemistry; Reagents; Removal; Response surface methodology; Studies; Sugar; Surface Properties; Suspended particulate matter; Textile Industry; Textile industry wastewaters; Textiles; Total suspended solids; Vicia faba; Vicia faba - chemistry; Waste Water - analysis; Wastewater; Wastewater treatment; Water Pollutants, Chemical - analysis; Water Purification - methods; Water treatment
• ISSN: 0273-1223; 1996-9732
• DOI: 10.2166/wst.2016.480

The Vicia faba membranes are an abundant and a low cost product. In the present research paper, the extracted Vicia faba mucilage was tested as an eco-friendly flocculant for textile wastewater treatment. Its performance as flocculant, in decolorization, chemical oxygen demand (COD) removal and the concentration of total suspended solids was checked. The natural extracted product was characterized using infrared spectroscopy. The total sugars were determined in the extracted product. The effect study, followed by an optimization and modeling analysis, of some experimental parameters on the coagulation-flocculation performance, using Vicia faba mucilage (as a flocculant), combined with aluminum sulfate (as a coagulant), showed that the best conditions for the flocculation process were pH of the effluent about 7, flocculant dose about 6.75 mg/L, flocculation mixing time about 3 min and flocculation mixing speed about 30 rpm, leading to a decolorization equal to 92.32%, COD removal of about 97.52% and total suspended solids of about 15.3 mg/L. A comparison study between the flocculation performance of commercial reagents and the bio-agent showed that the natural product presented a good flocculation performance.