Removal of boron from aqueous solutions by continuous polymer-enhanced ultrafiltration with polyvinyl alcohol

Abstract

Boron is a highly contaminating metal due to its toxic effects for plants even at very low concentrations. Continuous polymer-enhanced ultrafiltration (PEUF) was applied for removal of boron from aqueous solutions. The effects of operating parameters on the performance of PEUF were investigated. A commercial polymer, polyvinyl alcohol (PVA) was used as the boron-complexing agent. The methodology consists of two steps: complexing boron with PVA following separation of boron and polymer complexes by ultrafiltration process. The pilot scale system utilized for the PEUF process accommodates a spiral-wound cellulose cartridge with 10,000 Da MWCO. The experimental parameters studied are metal/polymer ratio (loading) (0.01–0.5), pH (7–10), and the polymer characteristics such as molecular weight (M n) of the polymer and degree of hydrolysis (DoH). The results showed that PEUF could be a successful alternative method for removal of boron. The permeate flux remained constant at around 19 L/m2 hr throughout the run...