Kinetic and Isothermal Investigations of Cost-Effective Sorptive Elimination of Gentian Violet Dye from Water Using Haplophragma adenophyllum Biowaste

Abstract

A novel biosorbent, Haplophragma adenophyllum (HAB) was employed to explore the biosorption mechanism of Gentian Violet (GV) dye. The novel sorbent was characterized by using FTIR spectra and physiochemical analysis. The effect of different optimizing factors like HAB dosage, GV initial concentration, contact time between sorbent and sorbate, pH of a solution, and the temperature was studied. The optimum removal of GV by HAB was observed at pH 6.0. The equilibrium study was carried out using Langmuir and Freundlich isotherms. Experimental data fitted well in Langmuir isotherm indicating monolayer isotherm with qmax value obtained at optimum process condition of 13.21 mg/g. Kinetics study was carried out and followed by pseudo-second-order model. Thermodynamics studies reveal the endothermic reaction.

Kinetics and Isotherm Studies for Adsorption of Gentian Violet Dye from Aqueous Solutions Using Synthesized Hydroxyapatite

“…Nonlinear regression using least square method was used for the calculation of kinetic parameters while using nonlinear equations. The nonlinear forms of the kinetic models PFO and PSO are described by the following equations [ 13 , 14 , 21 ]: where q e and q t (mg/g) are the amounts of the solute adsorbed by the adsorbent at equilibrium and at time ( t ), respectively. k 1 (min −1 ) and k 2 (mg/g.min) are rate constants for PFO and PSO, respectively.…”

“…Nonlinear regression using least square method was used for the calculation of kinetic parameters while using nonlinear equations. Te nonlinear forms of the kinetic models PFO and PSO are described by the following equations [13,14,21]:…”

“…Also, there are other materials such as modified HAp that have been recently used for the adsorption of different types of dyes as represented in Table 2 [ 16 ]. HAp is a calcium phosphate used in various fields including medicine and chemistry, and it is identified as a good adsorbent material for the environmental processes due to its specific structure conferring ionic exchange property and adsorption affinity towards many pollutants such as heavy metal ions, phenols, and dyes [ 13 , 14 ]. According to several recent studies mentioned in Tables 1 and 2 and based on the value of maximum adsorption capacity ( q max ) in mg/g, it is obviously noted that HAp/hydrolyzed polyacrylamide 75 adsorbent with q max = 435.6 mg/g is better than potato peels ( q max = 33.55 mg/g) and yellow passion fruit ( q max = 16 mg/g) for the adsorption of methylene blue dye from aqueous solutions [ 16 ].…”

“…HAp/chitosan composite with q max = 769 mg/g is better than tamarind shell ( q max = 10.48 mg/g) and banana peels ( q max = 18.2 mg/g) for the adsorption of Congo red dye from aqueous solutions [ 16 ]. Anionic surfactant-modified activated carbon (ACMAS) with q max = 235.7 mg/g [ 17 ] and sodium dodecyl sulphate-modified magnetic nanoparticles (SDS-MNPs) ( q max = 166.6 mg/g) [ 18 ] are better than avocado seed powder ( q max = 95.5 mg/g) and Haplophragma adenophyllum biomass (HAB) ( q max = 13.21 mg/g) [ 13 ] for the adsorption of GV dye from aqueous solutions. Holarrhena antidysenterica (HA) biowaste which is chemically treated with tartaric acid shows better adsorption for GV dye with q max = 144.92 mg/g [ 14 ] than the nontreated (HA) biowaste ( q max = 128.2 mg/g) [ 14 ].…”

“…Among the above-mentioned methods, adsorption becomes more promising due to its high removal efciency, high adsorption capacity, nontoxicity, and its ability to be used for the same adsorption process for several times [11]. Agricultural wastes such as potato peels and avocado seed powder have been recently used as adsorbents for diferent types of dyes, as represented in Table 1 [12][13][14], but they need several pretreatment processes including washing, drying, sieving, and grinding before using them as adsorbents [15]. Also, there are other materials such as modifed HAp that have been recently used for the adsorption of diferent types of dyes as represented in Table 2 [16].…”