Micellar enhanced ultrafiltration (MEUF) using cetylpyridinium chloride (CPC) and hexadecyltrimethylammonium bromide (HDTAB) surfactants for Fluoride rejection: modeling and process optimization

Heydarnezhad, Sodabeh; Jafari, Ali; Mousavi, Seyyed AliReza; Shokoohizadeh, Mohammad Javad

doi:10.34172/jaehr.2026.537414.1444

Micellar enhanced ultrafiltration (MEUF) using cetylpyridinium chloride (CPC) and hexadecyltrimethylammonium bromide (HDTAB) surfactants for Fluoride rejection: modeling and process optimization

Document Type : Original Article

Authors

Sodabeh Heydarnezhad

Ali Jafari

Seyyed AliReza Mousavi

Mohammad Javad Shokoohizadeh

Department of Environmental Health Engineering, School of Health, Kermanshah University of Medical Sciences, Kermanshah, Iran.

10.34172/jaehr.2026.537414.1444

Abstract

Excess fluoride, being harmful to human health, should be removed from water using appropriate treatment techniques. This study aimed to employ a low-pressure membrane system as micellar-enhanced ultrafiltration (MEUF) for fluoride removal through experimental design, process optimization, and model development using response surface methodology (RSM). Independent variables investigated included pH (4–10), fluoride concentration (4–10 mg/L), and concentrations of the cationic surfactants cetylpyridinium chloride (CPC) and hexadecyltrimethylammonium bromide (HDTAB) (1–1.5 mM/L). Experiments were conducted using a dead-end filtration setup at a constant pressure of 100 kPa with a filtration time of 10 minutes. The experimental design followed the Box–Behnken method, and model performance was evaluated using analysis of variance (ANOVA) and software-based visualization.
ANOVA indicated a strong correlation between the experimental data and the developed model, with regression coefficients (R²) exceeding 0.9 for fluoride rejection with both CPC and HDTAB. Results showed that increasing CPC and HDTAB concentrations enhanced fluoride removal, while decreasing fluoride concentration also significantly improved removal efficiency. The optimal fluoride rejection achieved was 94.5% with CPC and 89.6% with HDTAB. At optimum conditions, flux values of 268.1 L/m²·h and 276.5 L/m²·h were obtained for CPC and HDTAB, respectively.

Overall, the findings demonstrate that the MEUF technique is highly effective for fluoride removal. At optimal operational conditions, maximum removal efficiency for CPC and HDTAB can be achieved as predicted by the fitted model.

Keywords

Ultrafiltration

surfactants

Fluoride

Box-Behnken

Water

Subjects