Table 21.

Summary of the salient advantages and limitations as well as development status for the most promising new techniques for polyamide membrane biofouling control.

Technique	Advantages	Limitations	Development Status
Membrane Modification
Coatings	Surface modification to discourage bio-adhesion	Mechanical and chemical instability Mixed results for biocontrol and membrane performance	R&D
Nanoparticles	Use of biostatic nanoparticles to discourage bio-adhesion	Mixed results for biocontrol Deleterious effects on membrane performance	R&D/Commercial
Graphene Oxide	Demonstrated resistance to biofouling Demonstrated resistance to chlorine Membrane specific flux improvement with similar salt rejections to polyamide membranes	Mixed results reported for GO membrane performance Possible scale-up issues	Early bench-scale R&D
Chemical
Chlorine Dioxide	Excellent biocide to penetrate EPS	Mixed results on polyamide membrane compatibility Forms chlorite and chlorate oxidative DBPs Capital intensive—on-site generation required Difficulty in measuring residual USEPA and OSHA limits on residual and exposure	Commercial (compatibility studies in R&D phase)
DCC	Some polyamide compatibility Superior inactivation of Pseudomonas aeruginosa to chlorine	Lacking regulatory approval as a biocide Expensive	Bench-scale R&D
NO Donor Compounds	Toxic to bacteria Disperses EPS	Lacking regulatory approval as a biocide Resistance of some bacterial populations	R&D
AOP	Effective at oxidizing chemical and biological oxygen demand	Limited to membrane pretreatment	Commercial/wastewater reuse applications
Extrapolative Cleaning	Cleaning early in conditioning/adhesion phases of biofouling development	Does not disinfect membrane Frequent membrane autopsies	Infrequently practiced