Removal and Recovery of Chromium from Solutions Simulating Tannery Wastewater by Strong Acid Cation Exchanger

Table 1

Manufacturer data of the resin (Rohm and Haas 1998 [20]).

(a) The properties of the resin, Amberjet 1200Na

Matrix	Styrene divinylbenzene copolymer
Functional groups	Sulfonic acid
Physical form	Insoluble, amber beads
Ionic form as shipped	Sodium
Total exchange capacity	2.0 meq/mL minimum (Na^+ form)
Moisture holding capacity	43 to 47% (Na^+ form)
Shipping weight	53 lbs/ft^3
Harmonic mean size	0.57 to 0.67 mm
Uniformity coefficient	1.2 maximum
Maximum reversible; swelling	Approximately 10%; (from Na^+4 form to hydrogen)

(b) Suggested operating conditions of the resin

pH range	0 to 14
Maximum operating temperature	250°F
Minimum bed depth	24 inch minimum
Service flow rate	1 to 6 gpm/ft^3
Maximum service velocity	25 gpm/ft^2
Regenerants (100%)	NaCl	HCl	H2SO4
Flow rate (gpm/ft^3)	2 to 8	2 to 5	2 to 20
Concentration (%)	10	4 to 10	1 to 8
Level (lbs/ft^3)	3 to 15	2 to 8	2.5 to 12.5
Minimum contact time	20 minutes
Slow rinse	15 gal/ft^3 at regeneration flow rate
Fast rinse	8 to 22 gal/ft^3 at service flow rate