Fabrication of a novel latex-based membrane for oily wastewater filtration: effect of degassing on the properties of membrane

Nitrile butadiene rubber latex/graphene oxide (NBR/GO) membranes were fabricated by latex compounding and curing method. This was a new method to produce membrane, thus, the steps in the production were needed to be evaluated to optimize the performance of the membrane. Degassing is an important step in the production of polymer-based membrane through the common phase inversion method. In this research, the need to perform the degassing step in the latex compounding and curing method was confirmed through the morphology study, permeation flux, and oil rejection rate performance of the new NBR/GO membrane. Membrane without-degassing was prepared for comparison, as well. The highest oil rejection rate was found to be 95.04% with permeation flux of 438.43 Lm(-2) h(-1) for the membrane without-degassing, at the operating pressure of 0.3 bar for 1000 ppm of oily wastewater concentration. While for degassed membrane, the oil rejection rate and permeation flux at the same filtration conditions were found to be 91.88% and 2720.53 Lm(-2) h(-1), respectively. Surface morphology of the membranes showed ridges and grooves as a result of folds that provided effective surface area for filtration of oily wastewater. From these results, it could be concluded that the degassing step could be eliminated in the preparation of the membrane through the latex compounding and curing method. This decision will reduce the time, cost, and energy for producing the membranes.

Automated summary

The necessity of degassing during the preparation of NBR/GO membranes was confirmed through morphology study and performance evaluation. Membranes without degassing showed better oil rejection rate, while degassed membranes had higher permeation flux.