Chemical Engineering January 2017 - 46

GF Piping Systems
TABLE 1. INDUSTRY ACCEPTED
STANDARDS FOR CHEMICAL PURITY AND
GRADES
No.
1
2
3
4
5
6
7
8
9
ID weld seam width
FIGURE 5. A closeup of a BCF fusion weld seam is shown here [3]
ultra-high purity, and ultra-pure, when
they have no such specific values,
then becomes almost euphemistic in
their generality. The three terms are
much like those of low-, medium- and
high-pressure steam, which are not
terms that hold universally accepted
values, but are instead based on the
relative steam pressure requirements
of a particular facility.
As an example, a hydrolysis coalgasification
process uses saturated
steam at 2,000 psig to break down the
structure of lignite coal, causing the
material to release its gases. In such a
coal-gasification facility the 2,000 psig
steam may be considered high pressure,
with medium- and low-pressure
values established relative to the highpressure
value.
On the other hand, in an active
pharmaceutical ingredient (API) processing
facility that produces and
uses steam at a significantly lower
pressure than that of the gasification
process, a 100 psig steam system
might be considered high pressure,
with medium- and low-pressure values
again established relative to the
high pressure.
This analogy applies to high purity,
ultra-high purity, and ultra-pure in
which their application and implication,
with regard to a purity quotient,
is wide ranging in accordance with the
chemical and the chemical's use. The
specific meaning of purity will thus
vary between chemicals, between
manufacturers, and between applications
of such chemicals. It therefore
becomes much more pragmatic to
simply segregate our three terms by
industry and not by the non-specific
46
purity values.
The primary industries that use
such purity terms, as mentioned
previously, include the electronics
and bioprocessing industries.
The electronics chemicals industry,
which includes the semiconductor
sector, typically refers to its purity
needs and requirements in utilizing
each of the three purity terms.
Whereas the bioprocessing industry,
which includes the pharmaceutical
sector, typically refers to its purity
needs and requirements simply
as high purity. As we move forward
with this article we will be focusing
more specifically on electronics
chemicals. So rather than continue
to make reference to all three
terms in a somewhat indiscriminate
manner we will, for this discussion,
simplify things by grouping all three
terms into the single catch-all term
high purity.
Electronics chemicals
The electronics industry covers the
manufacture of a wide range of sophisticated
components and end
products, including silicon wafers,
integrated circuits, printed circuit
boards, compound semiconductors,
optoelectronics (a subset of photonics),
solar panels and flat-panel
display products. In discussing this
topic I will make every effort to avoid
being drawn into the many sidebar
subjects this topic harbors. We will
instead stay focused on essential
criteria and considerations necessary
for various chemical processing
equipment used in the manufacture
of electronics chemicals.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
Purity or Grade
Absolv (Tedia designation)
Accugen (Anachemia trademark)
Acculute (Anachemia trademark)
Accusolv (Anachemia trademark)
Accutin (Anachemia trademark)
ACS (American Chemical Society)
Anhydrosolv (Tedia designation)
AR (MBI trademark)
AR Select (MBI trademark)
AR Select Plus (MBI trademark)
BIO (Tedia designation)
CP (Chemically Pure)
ChromAR (MBI trademark)
DriSolv (EMD trademark)
Environmental Grade (Anachemia trademark)
Environmental
Grade Plus (Anachemia
trademark)
FCC (Food Chemicals Codex)
GenAR (MBI trademark)
Guaranteed Reagent (GR; EMD trademark)
HPLC/Spectro (Tedia designation)
HR-GC OmniSolv Grade Solvents (EDM
trademark)
Laboratory
Labboratory Grade
Nanograde (MDI trademark)
NF (National Formulary)
OmniSolv Biosynthesis (EMD trademark)
OmniSolv Grade Solvents
OmniSolv HPLC Grade Solvents (EMD
trademark)
OmniTrace Grade Acids (EMD trademark)
OR (MBI trademark)
Practical
Primary Standard
Purified
Reagent
Residue Grade Solvents
ScintillAR (MBI trademark)
SilicAR (MBI trademark)
SpectrAR (MBI trademark)
StandARd (MBI trademark)
Standardized Solutions
Suprapur Grade Acids (EMD trademark)
Technical
Tracemetal (Tedia designation)
Tracemetal Plus (Tedia designation)
UltimAR (MBI trademark)
USP (U.S. Pharmacopeia)
USP/GenAR (MBI trademark)
Electronics chemicals are, in
many cases, considered " specialty
chemicals " and are intended for
use in the microscopically sensitive
manufacture of the above mentioned
products. Products that use
atmospheric and specialty gases,
photoresists, various ancillary
chemicals, wet processing chemicals,
CMP (chemical mechanical
planarization) slurries, thin-film metCHEMICAL
ENGINEERING WWW.CHEMENGONLINE.COM
JANUARY 2017
http://WWW.CHEMENGONLINE.COM
Chemical Engineering January 2017

Table of Contents for the Digital Edition of Chemical Engineering January 2017
