Ion Exchange Resin

Ion exchange is a reversible chemical reaction wherein an ion (an atom or molecule that has lost or gained an electron and thus acquired an electrical charge) from solution is exchanged for a similarly charged ion attached to an immobile solid particle. These solid ion exchange particles are either naturally occurring inorganic zeolites or synthetically produced organic resins. The synthetic organic resins are the predominant type used today because their characteristics can be tailored to specific applications. An organic ion exchange resin is composed of high molecular weight polyelectrolytes that can exchange their mobile ions for ions of similar charge from the surrounding medium. Each resin has a distinct number of mobile ion sites that set the maximum quantity of exchanges per unit of resin. Ion exchange is a simple process where an organic molecule has been substituted with acid or base exchange sites. As a solution with exchangeable ions passes through the resin, the ions are captured and exchanged for the ions on the resin. For example, some weak acid ion exchange resins can use the carboxylic acid radical, in the sodium form, R-COO-Na as the exchange site. As solutions of metal ions such as Magnesium (Mg), Calcium (Ca), or Copper (Cu) pass through the resin, they are exchanged for the Na (Sodium) at that site. The molecule would now appear like this R-COO-Ca, for a Calcium exchange.

R-COO-Na + Ca+2 = R-COO-Ca + 2 Na+

These resins are used in water softeners where the alkaline earth metals such as Calcium and Magnesium are exchanged for Sodium. In a water softener Sodium Chloride (salt, NaCl), is used to "regenerate" the resin. The salt solution is passed through the resin in very high concentrations and the sodium displaces the metals attached to the active sites. When the concentration of sodium is low, the sites prefer the alkaline metals again and the resin can be used to "soften" water again. 

Available Types Of Resin

Model Type Form EC-8 St Acid Gel Cation 8% Cross Link Na EC-8L St Acid Gel Cation Large Bead 8% Cross Link Na EC-8B St Acid Gel Cation Black 8% Cross Link Na EC-8FM St Acid Gel Cation Fine Mesh 8% Cross Link Na EC-10 St Acid Gel Cation 10% Cross Link Na EC-8H St Acid Gel Cation 8% Cross Link H EC-8BH St Acid Gel Cation Black 8% Cross Link H EA-S1-Cl St Base 1 Gel Anion C1 EA-S1-OH St Base 1 Gel Anion OH

Model Type Form EA-S1-AC St Base 1 Gel Acrylic Anion C1 EA-S1M St Base 1 Macro Anion C1 EA-S2-Cl St Base II Gel Anion C1 EA-S2MN St Base Macro Anion C1 EA-WM Weak Base High Porous Anion FB EMB-1-OH-H Mixed Bed 60% 40% St Base 1 OH/H EMB-1 U Mixed Bed 60% 40% St Base 1 Ultra OH/H ECH5-NA Chelation Cation Na

Ion Exchange Equivalent Resin Reference Chart

ECOLOGIX SYSTEMS		MITSUBISHI	DOW	ROHM & HAAS		SYBRON		PUROLITE
		DIAION	DOWEX	AMBERLITE	DUOLITE	LEWATIT	IONAC
CATION	MESH
EC-8	16-50	SK1B	HCR-S	IR-120	C-20/225	S-100	C-249/298	C-100
EC-8L	30+	SK1BL	MRTHON C	AMBJ-1200		S-100	C-253	PF C-100
EC-8FM	40-70					KPS-2450	C-266	C-100 EFM
EC-8B	16-50			IR-120B			C-249
EC-10	16-50	SK110	HGR-W2	IR-122	C-255	S-110/115	C-250/299	C-100X10
EC-10L	30+		MRTHON C-10	AMBJ 1500				PF C-100X10
EC-10B	16-50
EA-SM	15-35	PK-216/228	MSC-1	AMB 200/IR-200	C-26	SP-112/120	CFP-110	C-150/160
EA-WG	16-50	WK-40	CCR-2	IRC-84	C-433	CNP/CC		C-104E
EA-WM	16-50	WK-20	MAC-3/CCR-2	IRC-76/84	C-464	CNP-80	CC	C-105/106
ANION
A-S1	16-50	SA10A	MRTHON A	IRA-400	A-109	M-500/511	ASB-1	A-600
A-S1P	16-50	SA12A	SBR-P	IRA-402/420	A-113	M-504/510	ASB-1P/A104	A-400
A-S2	16-50	SA20A	SAR	IRA-410/416	A-104	M-600/610	ASB-2/A550	A-300
A-S1M	16-50	PA-308/312	MSA-1	IRA-900	A-161	MP 500	A-641	A-500
A-S1M	16-50	PA-306/308		IRA-901/904		MP 500A	A-642	A-500P
A-S2M	16-50	PA-412/416	MSA-2	IRA-910	A-162	MP 600	A-651	A-510
A-WM	16-50	WA-30	MWA-1	IRA-93/95/96	A-378		AFP-329	A-100 E
A-S1MN	16-50			IRA-966			SR-6	A-520 E
A-S1MNS	16-50						SR-7
A-WACF	16-50	WA10/11		IRA-67/68			A375	A-845
A-S1AC	16-50			IRA-458	A-132	AP 247A	A475	A-850 E
A-S1ACM	16-50			IRA-478		AP 246	MACRO T	A-870
MIXED BED
MB-1		MI-700G	MR-3	IRN-150	ARM-381	SM 600KR	NM-60	NRW-37
MB-U		SMNUP					NM-92	EX-MB
CHELATES
CH-4	16-50		A-1	IMCGT73				S-920
CH-5	16-50	CR-11	XFS-4196	IRC-718/748	C-466	TP-207/208	SR-3/4	S-930
CH-6	16-50			IRC-746/747		TP-260	SR-5	S-950