Preparation of nano zero-valent aluminum for one-step removal of methylene blue from aqueous solutions: cost analysis for scaling-up and artificial intelligence

Abstract

Methylene blue (MB) is a heterocyclic aromatic dye that is difficult to biodegrade due to its complex chemical structure. In this study, chemically prepared nano zero-valent aluminum (nZVAl) was investigated for the first time for one-step removal of MB from aqueous solutions under different experimental factors (pH, dosage, time, MB concentration, stirring rate, temperature, detergents, and ionic strength). The prepared nZVAl material was characterized using XRD, TEM, SEM, EDS, and FTIR. Results indicated that at an initial MB concentration of 10 mg/L, pH 10, nZVAl dosage 1.0 g/L, stirring rate 200 rpm, and temperature 30 °C, the removal efficiency of approximately 99.0% was achieved within an equilibrium time of 90 min. An improvement in MB removal efficiency was observed in the presence of inorganic salts, while the presence of detergents resulted in a reduction in MB removal efficiency. The isotherm adsorption data were best fitted by the Freundlich isotherm model (R2: 0.9569), while the kinetic data were well described by the pseudo-second-order (PSO) model (R2: 0.9999). Based on the thermodynamic study, the MB adsorption process is physically diffusion-controlled. The adsorption of MB onto nZVAl was accurately described using an artificial neural network (ANN) with a structure of 11–10–1 and R2 of 0.97. The overall cost of scaling up the adsorption unit to be used for MB removal from aqueous solutions under the optimum conditions is about US$1.31/m3. Consequently, this study opens the door for other researchers to test nZVAl in treating real textile wastewater.

A Novel Nanogold Composite Fabrication, Its Characterization, and Its Application in the Removal of Methylene Blue Dye from an Aqueous Solution

“…In contrast, the Dubinin-Radushkevich (D-R) model was employed to determine the apparent free energy of adsorption (E), which is commonly used to differentiate between physical and chemical adsorption. The adsorption energy calculated from the D-R isotherms for MB on NGC indicated physical adsorption [62][63][64], with Q m values decreasing as temperature increased, suggesting an exothermic adsorption process [65].…”

Predicting Cu(II) Adsorption from Aqueous Solutions onto Nano Zero-Valent Aluminum (nZVAl) by Machine Learning and Artificial Intelligence Techniques

“…Nano-scale zero-valent aluminum (nZVAl) particles were synthesized via the sodium borohydride reduction method (NaBH 4 , Winlab Co., UK) [21,40]. Briefly, aluminum sulfate (Al 2 (SO 4 ) 3 •18H 2 O, Loba Chemie, India) was dissolved in distilled water and the mixture was aggressively agitated at 500 rpm by a magnetic bar.…”

“…The nZVAl material has been evidenced to be effective in removing non-biodegradable pollutants by generating hydroxyl radicals and sulfate in the aqueous medium [20]. Many researchers have reported that nZVAl was effective in removing phenol, nitrobenzene, perchlorate, chromium(VI), chloride, nitrate, dye compounds, bisphenol A, and hexabromocyclododecane from contaminated water [20][21][22]. Nanoscale ZVAl is an active and stable metal with a large surface area, having a wide range of versatility and flexibility for in-situ applications.…”

“…These operating conditions are controlled by several factors, e.g., nZVAl dosage, treatment period, and solution pH. The values of these factors should also be optimized to maximize the nZVAl treatment patterns within a shorter time and economically feasible costs [21]. The proposed modeling techniques should be flexible and simple to predict the nZVAl treatment performance toward various and broad ranges of heavy metals when receiving non-linear input attributes [22].…”

Heptachlor Epoxide -Pesticide- Removal from Aqueous Solutions Using Nano Zero Valent Iron: Operating Conditions, Response Surface Methodology, and Artificial Intelligence Neural Networks

“…The elimination of toxic organic pollutants such as heptachlor epoxide were investigated utilizing several approaches, including degradation, adsorption, electrocoagulation, enzymes, bacteria, and nanotechnologies [13][14][15][16]. Nano zero-valet metals such as iron has been widely employed in wastewater treatment by adsorption and degradation process, especially for pesticide removal [17][18][19]. The utilization of nano zero-valent iron is a highly promising technology for eliminating not just organochlorine pesticides, but also a wide range of other micropollutants [20,21].…”