Application of filtration with PVDF-based membranes for the removal of natural organic material humic acid from water

It seen that natural organic substances in water resources cause undesirable problems. The most important among these problems is the formation of by-products harmful to human health and the environment, by the reaction of chlorine with humic acids or other compounds in the disinfection processes of water. For this reason, various methods continue to be used and developed in obtaining drinking water from water sources. Studies with membrane technology processes, which are economical and enviromentally, are increasing rapidly. In this study, where porous and homogeneous membrane synthesis was aimed. SEM and FTIR analyzes of the synthesized membranes were performed. The effect of parameter variation on the morphology structure in membrane synthesis was investigated. In FTIR analysis, the bonds inside the membrane were analyzed. This analysis was applied to both clean and dirty membranes. The difference between the humic acid adhered to the membrane surface and a clean membrane was investigated. As a result of the membrane filtration process, UV analyzes of the permeate flux at a wavelength of 254 nm were performed. In this thesis, porous membranes were synthesized by phase transformation process using polyvinylidene fluoride (PVDF) as the main polymer. Blend and hybrid membranes were also synthesized by adding polyvinylpyrrolidone (PVP) and graphene oxide (GO) to the PVDF polymer, and the effect of parameter changes in the membrane solution was investigated. Among the synthesized membranes, it was observed that the removal performance was more successful in membranes synthesized with 10% by weight membrane solution. As a result of the study, the membrane with the best removal performance as 68.3% was synthesized from %10 PVDF solution by weight. The filtration performance was investigated by making membrane synthesis on different support layers. The content of the support layer was 100% PP, and different weights and structures were studied. The effect of the backing layer on the removal performance of the membrane differed for each nonwoven fabric. The best removal result in the number 1 support layer is 52%, and it belongs to the membrane synthesized from 10% PVDF solution. The best removal result in the 2nd support layer is 68.3% and belongs to the membranes synthesized from 10% PVDF solution. In the support layer number 3, the best removal results is 51% and belongs to the membrane synthesized from 10%PVDF+%1PVP solution. When the parameters in the synthesis conditions of the membrane changed, there were also changes in the membrane thickness and pore sizes. Membrane thickness are higher in membranes synthesized with solutions where the PVDF solution, which is dense among polymers, is higher by weight. The pore sizes, on the other hand, increased with the addition of the pore-forming PVDF polymer to the membrane solution. The GO additive also increased the pore size, but it was not as effective as the PVP polymer. It was observed that all synthesized membranes were porous and homogeneous. The flux value calculated as a result of the membrane filtration process differed in each membrane solution. The pore-forming effect of PVP also allows the passage of humic acid due to the presence of large and excess pores in the solution by weight.