Biomaterial Database

Zeolitic ammonium ion exchange for portable hemodialysis dialysate regeneration. 1995

J F Patzer, and S J Yao, and S K Wolfson

Department of Chemical Engineering, University of Pittsburgh, PA 15261, USA.

Ammonia removal from a recirculating dialysate stream is a major challenge in developing a truly portable, regenerable hemodialysis system. Three zeolites, type F, type W, and clinoptilolite, were found to have good ammonia ion exchange capacity with linear equilibrium ion exchange coefficients of 0.908, 0.488, and 0.075 L/g, respectively. The linear equilibrium ion exchange coefficient relates dialysate ammonia concentration (mumol/L) to the amount of ammonia absorbed by zeolite (mumol/g) at equilibrium. Ammonia uptake by zeolite powders was fast, with equilibrium reached within 15 sec. Zeolite ammonia ion exchange and regeneration through multiple cycles was studied using an ion exchange column containing clinoptilolite pellets. Zeolite ion exchange capability was regenerated by flushing the column with 2 mol/L sodium chloride after an ion exchange run. The column maintained ammonia ion exchange capacity through six ion exchange/regeneration cycles, demonstrating multiple dialysis use possibilities. Atomic absorption spectroscopy of the column effluent showed no detectible (< 1 part per million) Si or Al leached from the zeolite.

UI	MeSH Term	Description	Entries
D007475	Ion Exchange Resins	High molecular weight, insoluble polymers which contain functional groups that are capable of undergoing exchange reactions (ION EXCHANGE) with either cations or anions.	Ion Exchange Resin,Exchange Resin, Ion,Exchange Resins, Ion,Resin, Ion Exchange,Resins, Ion Exchange
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D012015	Reference Standards	A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.	Standard Preparations,Standards, Reference,Preparations, Standard,Standardization,Standards,Preparation, Standard,Reference Standard,Standard Preparation,Standard, Reference
D002852	Chromatography, Ion Exchange	Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.	Chromatography, Ion-Exchange,Ion-Exchange Chromatography,Chromatographies, Ion Exchange,Chromatographies, Ion-Exchange,Ion Exchange Chromatographies,Ion Exchange Chromatography,Ion-Exchange Chromatographies
D006435	Renal Dialysis	Therapy for the insufficient cleansing of the BLOOD by the kidneys based on dialysis and including hemodialysis, PERITONEAL DIALYSIS, and HEMODIAFILTRATION.	Dialysis, Extracorporeal,Dialysis, Renal,Extracorporeal Dialysis,Hemodialysis,Dialyses, Extracorporeal,Dialyses, Renal,Extracorporeal Dialyses,Hemodialyses,Renal Dialyses
D000641	Ammonia	A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.
D013054	Spectrophotometry, Atomic	Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.	Spectrophotometry, Atomic Absorption,AA Spectrophotometry,AE Spectrophotometry,Atomic Absorption Spectrophotometry,Atomic Emission Spectrophotometry,Atomic Spectrophotometry,Inductively Coupled Plasma Atomic Emission Spectrophotometry,Inductively Coupled Plasma Atomic Emission Spectroscopy,Spectrophotometry, Atomic Emission,AA Spectrophotometries,AE Spectrophotometries,Absorption Spectrophotometry, Atomic,Emission Spectrophotometry, Atomic,Spectrophotometries, AA,Spectrophotometries, AE,Spectrophotometry, AA,Spectrophotometry, AE
D017641	Zeolites	Zeolites. A group of crystalline, hydrated alkali-aluminum silicates. They occur naturally in sedimentary and volcanic rocks, altered basalts, ores, and clay deposits. Some 40 known zeolite minerals and a great number of synthetic zeolites are available commercially. (From Merck Index, 11th ed)	Zeolite