ASHLESS FILTER PAPER SELECTION

What is ashless filter paper?

Ashless quantitative and qualitative filter paper are acid-washed cellulose lined laboratory grade filters which can be used for any application where a filter is needed. The difference between quantitative and qualitative filter paper comes down to what you are filtering. In most applications, if gravimetric analysis will be done on precipitate recovered from the filter, then you should select quantitative papers. If you do not need to analyze the precipitate in the filter, you would be better off with a qualitatitive paper. Simply put, it does not make much difference in regards to cannabinoid processing because most likely we will not be analyzing the preciptate from the filter. What is more important is selecting proper speed and micron size for your application.

Sizes and Speeds

At BVV, we offer three different sizes of ashless filter paper. Each size comes in four different micron sizes or “speeds”. We offer 110mm, 125mm, and 180mm. Each size of filter paper is inteded to be slightly larger in diamter than it’s corresponding application. For instance, a 6″ Tri-Clamp Column would need 180mm filter papers. The filter paper will either be secured in place by a compression ring, or cut to size. Allowing the paper to sit inside the column in a dish shape will ensure nothing passes by the sides of the filter. Please refer to the following chart for specific sizes, speeds, and conversions:

-110mm Grade 42 – Slow – 2.5um (4.3 inches, 2.5 micron)

-110mm Grade 44 – Slow – 3um (4.3 inches, 3 micron)

-110mm Grade 40 – Medium – 8um (4.3 inches, 8 micron)

-110mm Grade 41 – Fast – 20-25um (4.3 inches, 20-25 micron)

-125mm Grade 42 – Slow 2.5um (4.9 inches, 2.5 micron)

-125mm Grade 44 – Slow – 3um (4.9 inches, 3 micron)

-125mm Grade 40 – Medium- 8um (4.9 inches, 8 micron)

-125mm Grade 41 – Fast- 20-25um (4.9 inches, 20-25 micron)

-180mm Grade 5 – Slow – 2.5um ( 7.1 inches, 2.5 micron)

-180mm Grade 6 – Slow – 3um (7.1 inches, 3 micron)

-180mm Grade 1 – Medium – 11um (7.1 inches, 11 micron)

-180mm Grade 4 – Fast – 20-25um (7.1 inches, 20-25 micron)

What is Ashless Filter paper Used For? 

Ashless filter paper is used for many different things related to extraction, winterization and filtration. Firstly, many people use coffee filters as a form of basic filtration inside hydrocarbon systems. Ashless filter paper is a much needed replacement for coffee filters as it is both stronger and performs higher quality filtration. We recommend a fast or medium speed filter that corresponds with your column size (180mm for 6″, 125mm for 4″, and 110mm for 3″).

Another prominent use for filter paper is molecular sieve filter driers. With our molecular sieves, we supply mesh gaskets but, adding an ashless filter paper will ensure no sieve dust enters your extract or other parts of your system. Sieve dust can cause extreme health issues so proper filtration is a must. At minimum, a 5 micron filter should be used with a molecular sieve, so we recommend a slow speed filter that corresponds to your column size (180mm for 6″, 125mm for 4″, and 110mm for 3″).

The most prominent use for filter paper is Buchner funnel filtration after a winterization process. For this application, there is a few different ways to go about selecting ashless filter paper. For a simple, single time funnel filtration, we recommend a slow speed that corresponds with your funnel size. For even better results, filtration should be attempted in stages corresponding to different winterization temperatures. For the first stage, winterize at about freezing for 4 hours and then filter through a fast speed filter. For the second stage, winterize for 4 more hours at about 0F and then filter through a medium speed filter. For the final stage, winterize overnight at -40F+ and filter through the slowest speed filter paper. This process will remove mass from the mixture in stages and will allow for faster filtration, easier coagulation of precipitate, and a more complete winterized product.