[sci.chem] Need help with chemical analysis

ceg@edsdrd.eds.com (Carlos Galarce) (05/10/89)

Hi folks!!

I need some help with a chemical compound that I am told is diatomaceus earth. It
is supposed to be mostly SiO2(~95%), with some other components. I guess this stuff
is used in filtering processes. 

The questions are:
	
	1) How do I go about getting it tested for its chemical components?
	2) What test(s) should be run on the compound for analysis?
	3) Where is a good lab that can do the test (hopefully in the 
	   midwest). Do universities do this kind of test?
	4) What amount of the compound is needed for the test(s)?
	5) About how much would I expect to pay for the test(s)?
	6) In what form are the test results delivered to me? Is there 
	   anything like a certified lab. (a seal of approval from somewhere).
	7) How much does this stuff cost in large quantities?

If you can answer any of these questions, please e-mail me and I will post answers if 
there is any interest.

I really appreciate any help in this matter.

Carlos
-- 
"Individuals have opinions, companies press releases"
Carlos E. Galarce                 USENET:  ...!uunet!edsews!edsdrd!ceg
Electronic Data Systems R & D     USNAIL:  3551 Hamlin Rd, 4th Floor, 
(313)-370-1555                             Auburn Hills, MI 48057

larry@kitty.UUCP (Larry Lippman) (05/12/89)

In article <113@merrimac.edsdrd.eds.com>, ceg@edsdrd.eds.com (Carlos Galarce) writes:
> I need some help with a chemical compound I am told is diatomaceus earth. It
> is supposed to be mostly SiO2(~95%), with some other components. I guess this
> stuff is used in filtering processes. 

	Actually, the percent composition of silicon dioxide in diatomaceous
earth ranges between 85% and 90%.

> 	1) How do I go about getting it tested for its chemical components?

	At a chemical testing lab. :-)  Seriously, though, WHY do you want
to have this material tested?  The simple truth of the matter is that
diatomaceous earth is not a particularly pure filter material; it's fine
for swimming pool filters and the like - but not for applications where
purity of filter materialis of great importance.

> 	2) What test(s) should be run on the compound for analysis?

	If I were _serious_ about this effort, I would look for Total
Organic Carbon (TOC), carbonate ion, sulfate ion, and then run say,
ICP (Inductive-Coupled Plasma) emission spectroscopy to asertain
elemental composition.
 
> 	3) Where is a good lab that can do the test (hopefully in the 
> 	   midwest). Do universities do this kind of test?

	I won't recommend a particular commercial lab, but as a clue
you may wish to check membership directories of AOAC (Association of
Official Analytical Chemists) and ASTM (American Society for Testing
MAterials).  Some universities offer analytical services to private
industry.

> 	4) What amount of the compound is needed for the test(s)?

	10 grams would be a rather generous sample.

> 	5) About how much would I expect to pay for the test(s)?

	For the above tests and a formal report, most commercial testing
laboratories would charge between $ 200.00 and $ 500.00.
 
> 	6) In what form are the test results delivered to me?

	Generally in the form of a formal "test report", which may or may
not contain a copy of say, the ICP elemental scan report.

> 	Is there anything like a certified lab. (a seal of approval from
> somewhere).

	Not for general analytical testing (there is state certification
for environmental and clinical testing, though).  However, AOAC and ASTM
member organizations are usually a safe bet.

> 	7) How much does this stuff cost in large quantities?

	Check out a copy of OPD Buyer's Guide or Chemical Week Buyer's
Guide for vendors and give 'em a call.  I have some diatomaceous earth
in my lab, but laboratory prices for its use as a filter aid and as
a chromatograph column packing bear no relationship to quantity pricing.

<>  Larry Lippman @ Recognition Research Corp. - Uniquex Corp. - Viatran Corp.
<>  UUCP:  {allegra|ames|boulder|decvax|rutgers|watmath}!sunybcs!kitty!larry
<>  VOICE: 716/688-1231, 716/773-1700        {att|hplabs|utzoo}!/
<>  FAX:   716/741-9635, 716/773-2488      "Have you hugged your cat today?"