Biosorption of Methylene Blue by De-Oiled Algal Biomass: Equilibrium, Kinetics and Artificial Neural Network Modelling

Abstract

The main objective of the present study is to effectively utilize the de-oiled algal biomass (DAB) to minimize the waste streams from algal biofuel by using it as an adsorbent. Methylene blue (MB) was used as a sorbate for evaluating the potential of DAB as a biosorbent. The DAB was characterized by SEM, FTIR, pHPZC, particle size, pore volume and pore diameter to understand the biosorption mechanism. The equilibrium studies were carried out by variation in different parameters, i.e., pH (2–9), temperature (293.16–323.16 K), biosorbent dosage (1–10 g L−1), contact time (0–1,440 min), agitation speed (0–150 rpm) and dye concentration (25–2,500 mg L−1). MB removal was greater than 90% in both acidic and basic pH. The optimum result of MB removal was found at 5–7 g L−1 DAB concentration. DAB removes 86% dye in 5 minutes under static conditions and nearly 100% in 24 hours when agitated at 150 rpm. The highest adsorption capacity was found 139.11 mg g−1 at 2,000 mg L−1 initial MB concentration. The process attained equilibrium in 24 hours. It is an endothermic process whose spontaneity increases with temperature. MB biosorption by DAB follows pseudo-second order kinetics. Artificial neural network (ANN) model also validates the experimental dye removal efficiency (R2 = 0.97) corresponding with theoretically predicted values. Sensitivity analysis suggests that temperature and agitation speed affect the process most with 23.62% and 21.08% influence on MB biosorption, respectively. Dye adsorption capacity of DAB in fixed bed column was 107.57 mg g−1 in preliminary study while it went up to 139.11 mg g−1 in batch studies. The probable mechanism for biosorption in this study is chemisorptions via surface active charges in the initial phase followed by physical sorption by occupying pores of DAB.

Biosorption, Isotherm and Kinetic Properties of Common Textile Dye by Phormidium Animale

“…Therefore, the continious experiments were carried out with 4 g/L biosorbent dosage. The results of biosorbent dosage experiment were supported by the results of previous dye biosorption studies reported in the literature (Saeed et al, 2010;Kousha et al, 2012;Maurya et al, 2014;Omar et al, 2018).…”

“…Similarly, in this study maximum percentage of dye biosorption rate occurred with 4 g/L adsorbent dosage as 98.29% (Figure 3). In addition to this, Maurya et al (2014) showed that the percentage of methylene blue dye biosorption rate by algal biomass was increased with the augmentation of biosorbent dosage. Recently, Omar et al (2018) reported that maximum malachite green dye removal rates were increased with the incensement of the amount of 3 algal biomasses called U. reticulata, S. crassifolium and G. corticata.…”

“…Bilinska et al (2016) stated that the final dye concentration of the dye liquor exhausted from textile material was 730 mg/L and the discharged of the real wastewater from industry contained 125 mg/L dye. The dye biosorption studies, published in the literature, were investigated the effect of dye concentration with different range of dye concentrations between 20 and 800 mg/L (Aksu and Tezer, 2006), 100 and 500 mg/L (Mona et al, 2011) and 25 and 2500 mg/L (Maurya et al, 2014). In this study the effect of dye concentration between 65-114 mg/L was examined in order to reach the closest dye concentration of the real dye containing wastewater which was mentioned by Bilinska et al (2016).…”

Linear and nonlinear sorption modelling for adsorption of atrazine onto activated peanut husk

“…The pH PZC of APNH was found to be 6.92. Generally, adsorption of cations is more favoured at pH > pH PZC while for anions at pH < pH PZC . However, the present study emphasizes the point that electrostatic interactions may not be the only reason for this adsorption process.…”

Insight into the adsorption mechanisms of methylene blue and chromium(iii) from aqueous solution onto pomelo fruit peel

“…The reason is that biosorbent has many signicant advantages such as simple implementation, very low cost, no or minimal use of chemicals and high efficiency, as compared to other materials. Several biosorbents have been used to treat MB and Cr(III) in waste solution such as oak banana peels, 11 sawdust, 27 lawn grass, 28 de-oiled algae, 29 mango leaves, 30 corn cobs, sunower 31 and grapefruit. 32 Pomelo, or Citrus maxima, has been popularly planted in Dong Nai Province, Vietnam.…”