Coagulation/flocculation of textile effluent using a natural coagulant extracted from Dillenia indica

Abstract

The aim of this study was to assess the efficiency of mucilage extracted from the fruit of Dillenia indica for enhancing coagulation in the treatment of textile effluent. The mucilage extraction was carried out in water at room temperature. The pH, concentration of coagulant FeCl3.6H2O, and concentration of mucilage solution were optimized with star-type central composite design (CCD). We were able to analyze the synergistic effects between the FeCl3.6H2O and mucilage concentrations: the process of coagulation/flocculation (CF) for chemical oxygen demand (COD) removal was more efficient at a low chemical coagulant concentration (8.00 mg L−1) and a higher natural coagulant (NC) concentration (15.00 mg L−1). This demonstrated the potential of this mucilage to treat textile effluents, with 67.66%% COD removal, 96.86% turbidity removal and 91.12% apparent color reduction. The characterization of the mucilage of Dillenia indica was done using Fourier transform infrared spectroscopy (FTIR) and solid-state cross-polarization magic angle spinning carbon-13 nuclear magnetic resonance (CP/MAS 13C NMR), and the signals obtained indicated the presence of polysaccharides, which are responsible for enhancing the CF process.

Optimization of pharmaceutical wastewater treatment by electrocoagulation and dual coagulation

“…(Lek et al, 2018). This increase in COD reduction may be due to the generation of Fe 3+ ion flocs from wastewater at higher dosage and also pollutant adsorption due to the presence of polysaccharide in AV known as acetylated mannan which plays an important role in treating wastewaters (Manholer et al, 2019). Further increasing the dosage above 4 resulted in no much significance in removal efficiency (Figure 4b); this may be due to saturation of agglomerates at one stage resulting in no influence on the formation of flocs (Precious Sibiya, Rathilal, & Kweinor Tetteh, 2021).…”

Textile Effluent Treatment Using Natural Coagulant Opuntia stricta in Comparison with Alum

“…Previously, turbidity removal has been analyzed as a surrogate measure to evaluate TSS removal. Turbidity removal attained was reported to be 91.3% by O. ficus indica , [ 39 ] 96% by D. indica , [ 44 ] and 85.4% by C. peruvianus . [ 40 ] Though, TSS removal by O. stricta looks slightly inferior to the turbidity removal by other PBCs, it gives a better and actual insight into the expected removal of suspended solids from textile effluent.…”

“…Maximum removals of COD (62%) by O. stricta are comparable to other PBCs such as Opuntia ficus‐indica (64.7%), [ 39 ] C. peruvianus (58.3%), [ 40 ] D. indica (67%). [ 44 ] However, it is somewhat inferior to COD removal attained by Moringa oleifera , i.e., 83%. [ 42 ]…”

“…The authors concluded that the best removal of color (91%), turbidity (96%) and COD (67%) was achieved at optimum combination of dosages for ferric chloride (8 mg L −1 ) and D. indica mucilage (15 mg L −1 ). [ 44 ]…”

Investigation of Pretreatment of Textile Wastewater for Membrane Processes and Reuse for Washing Dyeing Machines

“…Over the years, several studies have focused on the treatment of TWW with MSPs, but also on the pretreatment (e.g., sand filtration (SF), coagulation, combination of coagulation/flocculation) of TWW. These pretreatments were used to prevent membrane fouling and to achieve higher removal efficiency [ 11 , 12 , 13 , 14 , 15 , 16 ].…”