Application of nanofiltration membranes for removal of surfactants from water solutions

Abstract

Abstract. The objective of the study was to compare effectiveness of nanofiltration (NF) process for treatment aqueous solutions containing various types of surfactants (anionic, cationic and non-ionic). The experiments were conducted with the use of Microdyn-Nadir ® nanofiltration membranes (NP010 and NP030). The effect of surfactant type, its concentration and membrane cut-off on the process parameters (retention coefficient and permeate flux) was assessed. The experiments showed that separation of anionic and cationic surfactants depended on their concentration in the feed solutions. The retention coefficient of anionic surfactant ranged from 54 to 81% (NP010) and from 64 to 80% (NP030), while rejection of cationic surfactant varied from 48 to 85% (NP010) and from 51 to 88% (NP030). The values of retention coefficient of non-ionic surfactant were in the range of 69-77% and 79-88% for NP010 and NP030, respectively; and to a much lesser extent were depended on its concentration in the feed solutions in comparison with anionic and cationic compounds. Membrane characterized by smaller value of cut-off (NP030) allowed to obtain higher retention coefficients of surfactants. The membrane permeability deterioration was observed with the increase of surfactants concentration in the treated solutions. In all experiments, a sharp decline of the permeate flux was noticed for concentration below the CMC values.

Photo-Processes as Effective and Low-Cost Methods for Laundry Wastewater Treatment

“…Various methods have been developed to remove LAS surfactant in water and wastewater, such as adsorption [3][4], coagulation [2,[5][6], and filtration [7][8]. By adsorption, coagulation, and filtration techniques, the surfactant of LAS is only replaced from water to the adsorbents, coagulants and membranes with the same toxicity [1], then they are collected as hazardous solid wastes.…”

Recovery of Water from Textile Dyeing Using Membrane Filtration Processes

“…The fouling mechanisms, including concentration polarization, gel layer formation, and pore blocking, introduce additional resistance during the transport through the membrane due to increased osmotic pressure on the feed side [13,26]. Kowalska and Klimonda [19] showed that the surfactant concentration in the solution is the key parameter that has a significant influence on the separation performance. Increasing the dose of surfactant in the feed results in deterioration of the membrane permeability and strongly affects its separation properties [19].…”

“…The experimental results demonstrated that the concentration of the surfactant in the solution was the key parameter that significantly affected the process performance. Increasing the amount of surfactant in the feed impaired the permeability of the membranes and strongly affected their separation properties, which differed significantly at different concentrations [19].…”

“…There are also reports on membrane filtration used to remove surfactants [13,15,[17][18][19][20], where the influence of process parameters and the effect of detergent concentration and structure on the separation efficiency have been investigated in more detail.…”

Recycling of Catalysts from Surfactant Systems

“…Ultrafiltration membranes with a molecular weight cut-off (MWCO) of 5-10 kDa are suitable to filter micelles [21,23,24]. Nanofiltration membranes (WMCO < 1 kDa) can also be applied for this step [25]. The major drawback of MEUF is the flux through the membrane that defines the total separation time.…”