Mobilization of arsenic from contaminated sediment by anionic and nonionic surfactants

Abstract

The increasing manufacture of surfactants and their wide application in industry, agriculture and household detergents have resulted in large amounts of surfactant residuals being discharged into water and distributed into sediment. Surfactants have the potential to enhance arsenic mobility, leading to risks to the environment and even human beings. In this study, batch and column experiments were conducted to investigate arsenic mobilization from contaminated sediment by the commercial anionic surfactants sodium dodecylbenzenesulfonate (SDBS), sodium dodecyl sulfate (SDS), sodium laureth sulfate (AES) and nonionic surfactants phenyl-polyethylene glycol (Triton X-100) and polyethylene glycol sorbitan monooleate (Tween-80). The ability of surfactants to mobilize arsenic followed the order AES>SDBS>SDS≈Triton X-100>Tween 80. Arsenic mobilization by AES and Triton X-100 increased greatly with the increase of surfactant concentration and pH, while arsenic release by SDBS, SDS and Tween-80 slightly increased. The divalent ion Ca caused greater reduction of arsenic mobilization than Na. Sequential extraction experiments showed that the main fraction of arsenic mobilized was the specifically adsorbed fraction. Solid phase extraction showed that arsenate (As(V)) was the main species mobilized by surfactants, accounting for 65.05%-77.68% of the total mobilized arsenic. The mobilization of arsenic was positively correlated with the mobilization of iron species. The main fraction of mobilized arsenic was the dissolved fraction, accounting for 70% of total mobilized arsenic.

Krafft Point Prediction of Anionic Surfactants Using Group Contribution Method: First‐Order and Higher‐Order Groups

“…Anionic surfactants can lower the IFT more than amphoteric surfactants (Kamal et al, ). Surfactants are also used in the removal of organic contaminants or heavy metals from soil, using both anionic and nonionic surfactants (Lee et al, ; Liang and Peng, ). Cationic surfactants can be used to change the wettability of solid surfaces such as rock or polytetrafluoroethylene (PTFE) that are hydrophilic and hydrophobic, respectively (Thakkar et al, ).…”

Development of group-contribution models for use in surfactant selection – case studies of single and mixed surfactant applications

“…Anionic surfactants can lower the IFT between the two phases more than other amphoteric surfactants (Kamal et al, 2015). Other applications such as the removal of organic compounds or heavy metals from soil also utilize both anionic and nonionic surfactants (Liang et al, 2017). Cationic surfactants can be used to change the wettability of solid surface such as rock or polytetrafluoroethylene (PTFE) that are hydrophobic (Thakkar et al, 2017).…”