(718a) Ammonia Removal in Baitfish Retail Tanks and on-Farm Flow-through Grading/Holding Vats

Ahmadiannamini, P., University of Arkansas
Wickramasinghe, S. R., University of Arkansas
Qian, X., University of Arkansas

Ammonia Removal in Baitfish Retail
Tanks and On-Farm Flow-through Grading/Holding Vats

Pejman Ahmadiannamini1, Satchithanandam Eswaranandam1, Martin Christie2,
Ranil Wickramasinghe2, Xianghong Qian1

1Biomedical Engineering, University of Arkansas, Fayetteville,

2Chemical Engineering, University of Arkansas, Fayetteville,

Ammonia is the major metabolite
of proteins for fish. Zeolite 13X is a promising adsorbent materials with high
ion exchange capacity for ammonia removal in fishery water. However, the major
concern is that zeolite particles will tend to degrade in water. Moreover,
other ions and elements tend to leak into the solution preventing zeolite 13X
as an effective adsorbent for ammonium removal in fishery water. In order to
overcome the limitation of the direct adsorption approach, zeolite particles
were incorporated within polymeric matrices in three different conformations,
namely mixed matrix membranes; composite fibers; and pore-filled membranes.

Polymeric composite membranes
were prepared via wet phase inversion processes by incorporating zeolite 13X
particles into polysulfone matrices formed with and
without PEG as a molecular porogen. With increasing
zeolite content in the casting solution, the flux was decreased and the removal
capacity was enhanced. Adding PEG in the casting solution resulted formation of
more porous membranes with higher flux and lower of ammonium removal capacity. Similar
solutions were also employed to spin composite fibers. It was found that
employing PEG in spinning solutions resulted in lower ammonia removal
capacities. Moreover, increasing zeolite and polymer contents resulted in
increase and decrease of ammonia removal capacity of fibers, respectively.

Finally, zeolite pore-filled membranes were prepared via filtration of Zeolite
13X suspensions through flipped membranes in order to trap the zeolite powders
within macrovoids of the membranes. To prevent
particles shedding, the membranes were capped via interfacial polymerization
method using an aqueous solution of piperazine and a
solution of trimesoyle chloride in n-hexane. Higher
zeolite particles were incorporated via pore-filled membranes compared to the
mixed matrix membranes.Inductively coupled plasma
mass spectrometry (ICP-MS) analysis showed no evidence of ion leakage into
water treated by prepared zeolite 13X-polysulfone composite materials.






Schematic representation of zeolite
13X-polysulfone composite membranes: (A) mixed matrix membrane; (B) pore-filled