Getting the Most Production from my DW-R Resin
15) What is the difference between exhausted resin and saturated resin?
Exhausted resin is resin that has all of the active exchange sites loaded with ions exchanged from the process. The resin literally gives up hydrogen, which is replaced with ions (i.e. salts) from your B-100.
Saturated resin is resin that has adsorbed all of the glycerin and water that it can hold. If the resin is exhausted, it will also lose some of its capacity to absorb water and glycerin.
16) How do I restore the capacity of my DW-R™ resin for removal of glycerin and water?
If the application point for DW-R™ is prior to demethylation, it can be washed with methanol to restore absorption capacity.
17) Can I wash the resin with methanol if I am using it for final polishing after demethylation?
This is not a good idea because the residual methanol will get pushed out of the resin and end up in your finished B-100.
18) What are the recommended steps for washing with methanol?
Drain all of the B-100 from your exchange column.
Rinse the DW-R™ resin with two bed volumes of clean methanol at a rate of one bed volume per hour. You will notice that the methanol is discolored by the glycerin.
Repeat the procedure with one more bed volume of methanol at a rate of one bed volume per hour. .
Save the dirty methanol for use in transesterfication.
19) How do I tell when the DW-R™ resin is exhausted?
If the product is exhausted this can be detected by a simple test of the conductivity of the wash water. Mix one part of biodiesel to three parts of distilled (or deionized) water, shake, and then let them separate. Then measure the conductivity of the water phase. You will see the conductivity rise quickly when the DW-R™ is exhausted. You should also monitor clarity of the B-100. The turbidity will increase when the DW-R™ is exhausted.
20) How do I unload my DW-R™ resin when it is exhausted?
It is a good practice to back flow on bed volume of B-100 to fluff the bed.
Next you should drain down the B-100, and remove the resin.