03-20-02 00:04
No 285231
Looking for an informative link to the grading system of chemicals (lab, reagent, technical, etc).
If one were to purchase in bulk a certain grade of chemical, and then transfer to smaller containers, does the grade stay the same, or what? How does this work? Assuming one were selling the smaller containers.
(Hive Bee)
03-20-02 01:41
No 285281
Silly Bee thats a refrence as to how pure it is.
USP being just about the highest grade there is a 10
(Uninted States Pharmacy Grade)
ACS grade = very high grage or a 10
reagent grade = very high grade another 10
industrial grade = can vary a bit 7
technical grade = can vary a bit 7
Basically we're worried about things like heavy metals
such as lead thats known to make people sick.
Also mercury content for certain materials.
Usually distilling is hte best way to clean up what
your going to use. But ask before you do something
because it might have to bee handled a certain way.
Like some chems decompse when heated too much. For
instance the element
exampilium
it decomposes into crappium at 200C its Boiling
point at regular atmospheric temp is 220. So
we have a solution containing exampilium and it
happens to bee contaminated with PVP
poly vinyl providone (i probally misspelled it)
a very REAL contaminant introduced to us by our
friends at the DEA. PVP is a solid so we dont have
to worry about it distilling over beecause its not
a liquid. So we just have to worry about lowering that
boiling point. So we just Whip Out our vaccume pump
and LOWER the pressure inside the distillation kit.
Sucking all the air out REDUCES the boiling point.
It just so happens that a vaccume pump can lower the
boiling point of exampillium to 170C Great thats below
the temp that it decomposes at! So there you have it
Pure Exampilium.
contaminants gets left behind depending on what it is.
Seig Heil Uber Allies !
(Newbee)
03-20-02 01:44
No 285283
I know what it is. I asked how it was applied. If you take 1Kg of something that is Lab grade, and divide it into 100mL containers, is it still classified as Lab grade, or is it required to test each bottle again, to have a certain class, or what?
(Hive Prodigy)
03-20-02 05:14
No 285344
I don't remember when or where, but a link to a specific chart about this has been posted before. It listed all the grades in descending order of quality, and the standards that comprise their value.
PrimoPyro
Vivent Longtemps La Ruche!
(Chief Bee)
03-20-02 12:46
No 285484
Hey? Is anybody listening to the guy's actual question?
The following is an application of GMP and ISO 9000 to USP PG, and should be applicable to all other chemicals too. AFAIK, only USP and ACS grade have compulsory certification, reagent/lab/technical grade is up to you to grade.
2.2.4 Propylene Glycol USP/EP Recertification
Propylene Glycol USP/EP received in bulk can either be stored in an intermediate bulk tank for further use or be packed in drums, IBC’s or smaller packaging before being stored in warehouses, re-shipped or repacked. In such cases of intermediate handling, a recertification process must be applied as follows:
2.2.4.1 Intermediate bulk storage
If the product is unloaded into an intermediate and not emptied (drained) storage tank and/ or mixed with another lot, the initial analytical data are no longer valid. A new lot number must be assigned and a new certificate of conformity must be issued in conformance with the USP/EP requirements. In case a certificate of analysis is required, new analyses must be performed, reporting actual test results.
2.2.4.2 Packaging operations
When bulk product is packed in drums, IBC’s or smaller packaging, each packed lot must be sampled in accordance with an adequate and documented sampling technique (see Chapter 7) and key point controls must be performed on a composite sample representative of the whole lot. If these key point controls are in accordance with the sales specifications and there has been no mixing with another lot, the data mentioned in the certificate of analysis of the bulk product from which the packaging was performed can be passed over to the packed lot and be used for further shipments.
http://www.cefic.be/sector/popg/guide990
(Hive Bee)
03-23-02 13:39
No 286997
Thank you Rhodium, that's what I was interested in!
~ no one important