Effects of Preparation and Experimental Conditions on Removal of Phenol by Surfactant‐modified Zeolites

Abstract

The removal of phenol from aqueous solutions using surfactant-modified clinoptilolite-rich tuffs (SMZ) prepared from two Mexican zeolitic tuffs (Chihuahua and Oaxaca) was investigated. Sodium homoionization of the zeolitic rocks was performed before they were modified with the surfactants: hexadecyltrimethylammonium chloride or bromide and bencylcetildimethylammonium chloride. The surfactants in the modified zeolitic materials were determined considering the total carbon in the samples. The phenol removal was determined in a batch system taking into consideration the different quantities of surfactants in the zeolitic tuffs, contact time, pH and initial phenol concentration. The phenol was determined in the aqueous solutions by UV/Vis spectroscopy. Results showed that the formation of a hemimicelle or admicelle on the zeolites depended on the initial surfactant concentration and they were responsible for the type of interactions between the phenol and the surfactant-modified zeolites. Phenol adsorption by the surfactant-modified zeolites was carried out in approximately three hours. Phenol adsorption data was best adjusted to the pseudo-second order kinetic model. Both, surface properties of the surfactant-modified zeolites and pH of solution play an important role in the removal of this pollutant from aqueous solutions and they are responsible for the type of mechanism involved.

Kinetic model selection and the Hill model in geochemistry

“…The PSO model is arguably the most widely used kinetics sorption model and was used in the studies by Blandhard 1984, Ho andMcKay (1998b) and Chowdhury and Das (2011). It is often recommended because it considers system heterogeneity (Diaz-Nava et al 2008). The nonlinear (preferred) form of the PSO equation is:…”

Phenol sorption on surfactant-modified Mexican zeolitic-rich tuff in batch and continuous systems

“…In a previous work [10] was investigated the kinetic of the phenol adsorption by the SMZ used in the present work and it was found that phenol adsorption by the surfactant-modified zeolites reached the equilibrium in approximately 3 h and the equilibrium was main- tained until the final experimental time (72 h). It was also found that phenol adsorption data was best adjusted to kinetic model of pseudo-second order.…”

“…In a previous work Díaz-Nava et al [10] determinated the kinetic parameters in order to know the phenol sorption behavior using surfactant-modified natural zeolites considering the preparation conditions of the SMZ, the type of surfactants which were used to modify the characteristics of the zeolitic surface, the source of the zeolitic material, the pH of phenol solutions as well as the concentration of phenol in the solutions in batch system. It was found that the sorption equilibrium on SMZ for phenol was reached in 24 h. Therefore in this paper the experimental conditions to obtain the isotherm curves were chosen according to the kinetic results.…”

“…Adsorption in particular has been an effective separation process for a wide variety of applications [5,6]. Sorption of phenol has been studied in different materials such as activated carbon, calcined hydrotalcites, organoclays and zeolites [7][8][9][10][11][12][13][14][15][16][17].…”

Reactive Extraction of p-Nitrophenol Using Tributylphosphate in Solvent Naphtha or n-Octanol

“…Phenolic compounds are important raw materials for fine chemicals and have been widely used in the fields of pharmaceuticals, feeds, resins, dyes, pesticides, and so forth . These phenolic compounds are highly toxic by ingestion or inhalation at the low concentrations . Nitrophenol and its isomers, which have been widely used in the production of pesticides, insecticides, and herbicides, have caused great harm to the environment and humans.…”