D301 is an extremely durable macroporous weak base anion exchange resin characterized by tertiary amine groups attached to a styrene divinylbenzene copolymer matrix. It has a unique physical structure which gives it superior kinetics and greater resistance to osmotic shock than gel type weak base anion exchangers.
D301 yields exceptionally high operating capacity on caustic soda regeneration and has low rinse requirements. It has a higher resistance to organic matter than gel type anion exchangers.
D301 is supplied as moist spherical beads in free base form, ready to use. D301 removes free mineral acid ions like chloride, sulphate, nitrate etc. but will not remove weak acid ions like silica and carbon dioxide. In a demineralization system, D301 can be placed preceding a strong base anion exchanger. This system offers a more economical regeneration cost, as D301 operates at a very high regeneration efficiency in comparison to strong base exchangers. Additional savings can be achieved by regenerating the weak base and strong base exchangers in series. The design must, however take care to prevent silica precipitation on the weak base exchanger. D301 placed preceding a strong base anion exchanger also serves to protect it from organic fouling.
APPLICATIONS: D301 is suitable for demineralization of water for industrial steam generation operated with co-current or modern counter-current systems. It is able to remove high molecular weight organic materials from the influent water, thus protecting a following strong base resin from fouling. The organics are readily eluted, and the regenerated resin shows good rinse behavior, and a very acceptable operating capacity on relatively high-TDS waters.
While there are several other specially-tailored macroporous intermediate-base resins in the D301 series, D301 itself is probably the most generally useful. A suitably-graded version, D301MB is recommended for use in conjunction with 201 II type or 201x4 in layered-bed anion exchange systems.