Modeling of Malachite Green Removal from Aqueous Solutions by Nanoscale Zerovalent Zinc Using Artificial Neural Network

Abstract

Abstract:The commercially available nanoscale zerovalent zinc (nZVZ) was used as an adsorbent for the removal of malachite green (MG) from aqueous solutions. This material was characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The advanced experimental design tools were adopted to study the effect of process parameters (viz. initial pH, temperature, contact time and initial concentration) and to reduce number of trials and cost. Response surface methodology and rapidly developing artificial intelligence technologies, i.e., artificial neural network coupled with particle swarm optimization (ANN-PSO) and artificial neural network coupled with genetic algorithm (ANN-GA) were employed for predicting the optimum process variables and obtaining the maximum removal efficiency of MG. The results showed that the removal efficiency predicted by ANN-GA (94.12%) was compatible with the experimental value (90.72%). Furthermore, the Langmuir isotherm was found to be the best model to describe the adsorption of MG onto nZVZ, while the maximum adsorption capacity was calculated to be 1000.00 mg/g. The kinetics for adsorption of MG onto nZVZ was found to follow the pseudo-second-order kinetic model. Thermodynamic parameters (∆G 0 , ∆H 0 and ∆S 0 ) were calculated from the Van't Hoff plot of lnKc vs. 1/T in order to discuss the removal mechanism of MG.

Removal of Crystal Violet by Using Reduced-Graphene-Oxide-Supported Bimetallic Fe/Ni Nanoparticles (rGO/Fe/Ni): Application of Artificial Intelligence Modeling for the Optimization Process

“…This network consists of an input layer, hidden layers, and an output layer. All input weights were summed to create the output through the activation function [ 36 ] ( Figure 3 ). The tangent sigmoid transfer function (tansig) (Equation (7)) was used in the input–hidden layer, whereas the linear transfer function (purelin) (Equation (8)) was adopted in the output layer.…”

Reuse of Electrocoagulated Metal Hydroxide Sludge to Fluoride and Arsenic Removal by a Fixed-Bed Column in Continuous Operation

“…adsorption isotherm with an evident hysteresis loop (according to the IUPAC classification), implying the existence of mesopores structures in the material [39]. Furthermore, the existence of macropores is evidenced given that the hysteresis loop shifts approach relative pressure (p/p0)=1.…”

Mesoporous Mn-Doped Fe Nanoparticle-Modified Reduced Graphene Oxide for Ethyl Violet Elimination: Modeling and Optimization Using Artificial Intelligence

“…The results indicated that the process of EV removal by Mn-doped Fe/rGO obeyed the pseudo-second-order kinetics model and Langmuir isotherm, and the maximum adsorption capacity was 1000.00 mg/g. This study provides a possibility for synthesis of Mn-doped Fe/rGO by co-precipitation as an excellent material for EV removal from the aqueous phase.Processes 2020, 8, 488 2 of 31 and textile industries [4][5][6][7]. It is estimated that about 15% of the total world production of dyes is lost during the dyeing process, and this quantity is then released into the wastewater [8].Ethyl violet (EV) (C 31 H 42 ClN 3 , MW = 492.15 g/mol) is a typical cationic dye of triphenylmethane (Figure 1), which is toxic and has strong coloring ability and is difficult to degrade in the natural environment.…”

“…Current approaches to detoxify the dye wastewater include Fenton or photo-Fenton oxidation, reduction by zero-valence metals, coagulation/flocculation, electrochemical oxidation, biological treatment, membrane filtration, ozonation, electrochemical degradation and adsorption [1,[9][10][11][12][13][14][15]. Among these options, zero-valence metals have attracted considerable attention in industries due to their ease of synthesis and operation, low cost and high adsorption capacity [9].Processes 2020, 8, x 2 of 31 and textile industries [4][5][6][7]. It is estimated that about 15% of the total world production of dyes is lost during the dyeing process, and this quantity is then released into the wastewater [8].Ethyl violet (EV) (C31H42ClN3, MW = 492.15 g/mol) is a typical cationic dye of triphenylmethane (Figure 1), which is toxic and has strong coloring ability and is difficult to degrade in the natural environment.…”

“…Processes 2020, 8, 488 2 of 31 and textile industries [4][5][6][7]. It is estimated that about 15% of the total world production of dyes is lost during the dyeing process, and this quantity is then released into the wastewater [8].…”