US20050025660A1

US20050025660A1 - Method of tracing corrosive materials

Info

Publication number: US20050025660A1
Application number: US10/631,607
Authority: US
Inventors: John Hoots; Barbara Davis
Original assignee: Ondeo Nalco Co
Current assignee: ChampionX LLC
Priority date: 2003-07-31
Filing date: 2003-07-31
Publication date: 2005-02-03

Abstract

A method of using an inert fluorescent tracer in an industrial water system wherein the water of said industrial water system contains a certain amount of a corrosive material, is described and claimed, as is a method of using an inert fluorescent tracer to trace the corrosive material itself. Combinations of inert fluorescent tracers in corrosive materials are also described and claimed.

Description

FIELD OF INVENTION

This invention is in the field of industrial water systems. Specifically, this invention is in the field of the use of fluorescent tracers in the water of an industrial water system where significant amounts of a corrosive material are present.

BACKGROUND OF THE INVENTION

Industrial water systems exist so that necessary chemical, mechanical and biological processes can be conducted to reach the desired outcome. Industrial water systems include the following: cooling water systems, including open recirculating, closed and once-through cooling water systems; boilers and boiler water systems; petroleum wells, downhole formations, geothermal wells and other oil field applications; mineral process waters including mineral washing, flotation and benefaction; paper mill digesters, washers, bleach plants and white water systems; black liquor evaporators in the pulp industry; gas scrubbers and air washers; continuous casting processes in the metallurgical industry; air conditioning and refrigeration systems; industrial and petroleum process water; indirect contact cooling and heating water, such as pasteurization water; water reclamation and purification systems; membrane filtration water systems; food processing streams (meat, vegetable, sugar beets, sugar cane, grain, poultry, fruit and soybean); and waste treatment systems as well as in clarifiers, liquid-solid applications, municipal sewage treatment and industrial or municipal water systems.
While water is obviously the major component of an industrial water system there are typically other materials present in an industrial water system. These can include anything from innocuous materials all the way to highly corrosive materials. A corrosive material can be anything that attacks building materials or metals or anything that burns, irritates or destructively attacks organic tissues. Corrosive materials can be in the category of unwanted impurities or they can be present in the water in order to perform a needed function.
As is the case with many industrial water systems, many cooling water systems use treatment products to control undesirable phenomena such as scaling, corrosion, fouling and microbiological growth. These treatment products include chemical materials such as polymers, phosphates, phosphonates, azoles, zinc, molybdate, biocides, and other materials and are known to people of ordinary skill in the art of cooling water systems.
Treatment products are typically prepared by taking these chemical materials and formulating them into aqueous liquid phase products or solid products for distribution to and delivery into an industrial water system. Delivery into an industrial water system, can be accomplished by pump feed or edductor feed system for a liquid product, by solid product feeder for a solid product or even by manual addition of the treatment product for either liquid or solid product. A cooling water system, for example, can be set up to feed treatment product based on either a bleed/feed mechanism where the action of blowdown triggers a chemical feed pump or valve that feeds treatment product; or, in the alternative, the cooling water system feeds treatment product based on timers using a “feeding schedule” or flow meters on the make-up water line trigger the pumping of treatment product based on a certain amount of make-up water being pumped. A limitation of these control methods is that none of these systems measure the treatment product concentration directly online, so if there is a mechanical problem, for example, if a pump fails, a drum empties, or high, low or unknown blowdown occurs, system volume changes or makeup water quality changes; the correct treatment product concentration is not maintained. Because this problem is common, cooling tower systems are typically either overfed with treatment product to ensure the level of treatment product in the system does not drop too low as a result of high variability in product dosage or the treatment product is unknowingly underfed. Both overfeeding and underfeeding of treatment product are undesirable due to cost and performance drawbacks.
One aspect of known control schemes is addition of an inert fluorescent chemical tracer in a known proportion to the active component of the treatment product and feeding this mixture of treatment product and tracer to the cooling water system. Then a fluorometer is used to monitor the fluorescent signal of the inert fluorescent chemical. This technology is commercially available as TRASAR®, which is a registered trademark of Ondeo Nalco Company, Ondeo Nalco Center, 1601 W. Diehl Road, Naperville Ill. 60563, (630) 305-1000.
The fluorescent signal of the inert fluorescent chemical is used to determine how much inert fluorescent tracer is present, and by knowing the amount of inert fluorescent tracer that is present it is possible to determine the amount of treatment product that is present in the cooling tower. If the amount of treatment product that is present is not what is desired then the feed rate of treatment product can be adjusted to provide the desired amount of treatment product.
A known difficulty with the use of inert fluorescent tracers in industrial water systems is the susceptibility of some of them to degradation of their fluorescent signal upon contact, for a sufficient length of time, with corrosive materials. It would be desirable to have inert fluorescent tracers that are capable of maintaining their fluorescent signal in the presence of common corrosive materials.

SUMMARY OF THE INVENTION

The first aspect of the instant claimed invention is a method of using an inert fluorescent tracer in an industrial water system wherein the water of said industrial water system contains a certain amount of a corrosive material, comprising the steps of:

- 1) providing an industrial water system wherein the water of said industrial water system contains a certain amount of a corrosive material;
- 2) adding to the water of said industrial water system a treatment chemical wherein said treatment chemical includes an inert fluorescent tracer in a known proportion;
- 3) providing a fluorometer capable of detecting the fluorescent signal of said inert fluorescent tracer, wherein said fluorometer has a sample cell that corrosive materials can be placed in without rendering the sample cell unusable;
- b 4) using said fluorometer to detect and measure the fluorescent signal of said fluorescent tracer in the water of said industrial water system;
- b 5) using the detected and measured fluorescent signal to determine how much of the treatment chemical is present in the water of said industrial water system; and optionally;
- 6) adjusting the operating parameters of said industrial water system such that the amount of treatment chemical present is optimal for the operating conditions of said industrial water system.

The second aspect of the instant claimed invention is a method of tracing a corrosive material, comprising the steps of:

- (a) providing an industrial water system and a corrosive material that will be added to the water of the industrial water system;
- (b) placing in said corrosive material an inert fluorescent tracer which has a detectable fluorescent signal when placed in said corrosive material, wherein said inert fluorescent tracer is added to said corrosive material in a known proportion;
- (c) adding said corrosive material containing an inert fluorescent tracer to the water of said industrial water system;
- (d) providing a fluorometer capable of detecting the fluorescent signal of said inert fluorescent tracer, wherein said fluorometer has a sample cell that corrosive materials can be placed in without rendering the sample cell unusable;
- (e) using said fluorometer to detect and measure the fluorescent signal of said fluorescent tracer in the water of said industrial water system;
- (f) using the detected and measured fluorescent signal to determine how much of the corrosive material is present in the water of said industrial water system; and optionally
- (g) adjusting the operating parameters of said industrial water system such that the amount of corrosive material present is optimal for the operating conditions of said industrial water system.

The third aspect of the instant claimed invention is a composition of matter comprising

- a) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of 1,3,6,8-pyrene tetrasulfonic acid and the known salts of 1,3,6,8-pyrene tetrasulfonic acid; and
- b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl, concentrated H₂SO₄, glacial acetic acid, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, concentrated H₂SO₄is at least about 98 wt. % H₂SO₄in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water; wherein glacial acetic acid is at least about 100 wt. % acetic acid in water and wherein dimethylformamide is about 100 wt. % dimethylformamide.

The fourth aspect of the instant claimed invention is a composition of matter comprising

- a) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of 1,5-naphthalenedisulfonic acid and the known salts of 1,5-naphthalenedisulfonic acid, and
- b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl and concentrated H₃PO₄; wherein concentrated HCl is at least about 37 wt. % HCl in water and wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water.

The fifth aspect of the instant claimed invention is a composition of matter comprising

- a) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of isomers of anthracene disulfonic acid and salts thereof and
- b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water and wherein dimethylfornamide is about 100 wt. % dimethylformamide.

DETAILED DESCRIPTION OF THE INVENTION

Throughout this patent application the following terms have the indicated definitions:
“CAS #” refers to the Chemical Abstracts Services Registry Number.
Nalco refers to Ondeo Nalco Company, Ondeo Nalco Center, 1601 W. Diehl Road, Naperville Ill. 60563, telephone number (630) 305-1000.
The first aspect of the instant claimed invention is a method of using an inert fluorescent tracer in an industrial water system wherein the water of said industrial water system contains a certain amount of a corrosive material, comprising the steps of:

- a) providing an industrial water system wherein the water of said industrial water system contains a certain amount of a corrosive material;
- b) adding to the water of said industrial water system a treatment chemical wherein said treatment chemical includes an inert fluorescent tracer in a known proportion;
- c) providing a fluorometer capable of detecting the fluorescent signal of said inert fluorescent tracer, wherein said fluorometer has a sample cell that corrosive materials can be placed in without rendering the sample cell unusable;
- d) using said fluorometer to detect and measure the fluorescent signal of said fluorescent tracer in the water of said industrial water system;
- e) using the detected and measured fluorescent signal to determine how much of the treatment chemical is present in the water of said industrial water system; and optionally;
- f) adjusting the operating parameters of said industrial water system such that the amount of treatment chemical present is optimal for the operating conditions of said industrial water system.

Industrial water systems include the following: cooling water systems, including open recirculating, closed and once-through cooling tower water systems; boilers and boiler water systems; petroleum wells, downhole formations, geothermal wells and other oil field applications; mineral process waters including mineral washing, flotation and benefaction; paper mill digesters, washers, bleach plants and white water systems; black liquor evaporators in the pulp industry; gas scrubbers and air washers; continuous casting processes in the metallurgical industry; air conditioning and refrigeration systems; industrial and petroleum process water; indirect contact cooling and heating water, such as pasteurization water; water reclamation and purification systems; membrane filtration water systems; food processing streams (meat, vegetable, sugar beets, sugar cane, grain, poultry, fruit and soybean); and waste treatment systems as well as in clarifiers, liquid-solid applications, municipal sewage treatment and industrial or municipal water systems.
Treatment chemicals for use in industrial water systems include commercially available corrosion inhibitors, biological control agents, scale inhibitors, dispersants, coagulants, flocculants, and pH control agents. These commercially available products are well known to people in the art of industrial water chemistry.
1,3,6,8-pyrene tetrasulfonic acid and the known salts of 1,3,6,8-pyrene tetrasulfonic acid are inert fluorescent tracers that may be used with large amounts of concentrated HCl, concentrated H₂SO₄, glacial acetic acid, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, concentrated H₂SO₄is at least about 98 wt. % H₂SO₄in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water; wherein glacial acetic acid is at least about 100 wt. % acetic acid in water and wherein dimethylformamide is about 100 wt. % dimethylformamide. The preferred known salt of 1,3,6,8-pyrene tetrasulfonic acid for use with corrosive materials is the tetrasodium salt. This material is available from Nalco.
1,5-naphthalenedisulfonic acid and the known salts of 1,5-naphthalenedisulfonic acid disodium salt may be used in water containing large amounts of concentrated HCl and concentrated H₃PO₄; wherein concentrated HCl is at least about 37 wt. % HCl in water and wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water. The preferred known salt of 1,5-naphthalenedisulfonic acid for use with corrosive materials is the disodium salt. This material is available from Nalco.
Isomers of anthracene disulfonic acid and salts thereof, may be used in water containing large amounts of concentrated HCl, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water and wherein dimethylformamide is about 100 wt. % dimethylformamide.
Known isomers of anthracene disulfonic acid, and certain of their known salt forms include the following:

- CAS # 13189-75-8 1,5-anthracene disulfonic acid, sodium salt;
- CAS # 55750-36-2 1,8-anthracene disulfonic acid sodium salt;
- CAS # 61736-91-2 1,5-anthracene disulfonic acid;
- CAS # 61736-92-3 1,8-anthracene disulfonic acid;
- CAS # 61736-67-2 1,5-anthracene disulfonic acid, magnesium salt;
- CAS # 61736-93-4 1,6-anthracene disulfonic acid;
- CAS # 61736-94-6 1,7-anthracene disulfonic acid;
- CAS# 61736-95-6 2,6-anthracene disulfonic acid; and
- CAS# 61736-96-7 2,7-anthracene disulfonic acid.

The preferred isomers of anthracene disulfonic acid are 1,5-anthracene disulfonic acid, magnesium salt, 1,5-anthracene disulfonic acid, sodium salt and 1,8-anthracene disulfonic acid sodium salt and mixtures thereof. The most preferred isomer of anthracene disulfonic acid is about a 2:1 mixture of 1,5-anthracene disulfonic acid, sodium salt and 1,8-anthracene disulfonic acid sodium salt.
Isomers of anthracene disulfonic acid and their known salts can be obtained by following synthetic techniques known in the art of organic chemistry. See GB 1214256, A method of preparing anthraquinone 1,5-disulphonic acid, published Oct. 13, 1976, assigned to Imperial Chemical Industries, Studies on the Sulfonation of Anthracene. Part 1. Sulfonation in neutral or basic solvents, by John O. Morley, Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) (1976), (13), 1554-9, Studies on the Sulfonation of Anthracene. Part 2. Sulfonation in acetic acid and related solvents, by John O. Morley, Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) (1976), (13), 1560-4.
Fluorometers suitable for use in the instant claimed invention are commercially available from Nalco, these include: TRASAR® 8000, TRASARO® 3000, Xe-2 Fluorometer and a TRASAR® 350. Other suitable fluorometers are available from Spex. The preferred fluorometers are a TRASARO® 3000 unit and a TRASARS® Xe-2 Fluorometer.
How to set up and program a fluorometer and use it to measure the fluorescent signal of a fluorescent tracer is known to people of ordinary skill in the art of fluorometry. After the fluorescent signal of the inert fluorescent tracer is detected and measured, it is known how to correlate that information with the concentration of the inert fluorescent tracer and once the concentration of the inert fluorescent tracer is known that information can be used to determine the amount of treatment chemical present in the industrial water system and that information can be used to optimize the operation of the industrial water system.
The second aspect of the instant claimed invention is a method of tracing a corrosive material, comprising the steps of:

The inert tracers that can be used with the specific corrosive materials listed in the first aspect of the instant claimed invention are the same as those that can be used in the second aspect of the instant claimed invention. The fluorometers that can be used in the second aspect of the instant claimed invention are the same as those fluorometers that can be used in the first aspect of the instant claimed invention. How to set up and program a fluorometer and use it to measure the fluorescent signal of a fluorescent tracer is known to people of ordinary skill in the art of fluorometry. After the fluorescent signal of the tracer is detected and measure, it is known how to correlate that information with the concentration of the inert fluorescent tracer and once the concentration of the inert fluorescent tracer is known that information can be used to determine the amount of corrosive material present in the industrial water system and that information can be used to optimize the operation of the industrial water system.
The third aspect of the instant claimed invention is a composition of matter comprising

- c) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of 1,3,6,8-pyrene tetrasulfonic acid and the known salts of 1,3,6,8-pyrene tetrasulfonic acid,
- b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl, concentrated H₂SO₄, glacial acetic acid, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, concentrated H₂SO₄is at least about 98 wt. % H₂SO₄in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water; wherein glacial acetic acid is at least about 100 wt. % acetic acid in water and wherein dimethylformamide is about 100 wt. % dimethylformamide.

The amount of 1,3,6,8-pyrene tetrasulfonic acid or a known salt of 1,3,6,8-pyrene tetrasulfonic acid present in the corrosive material is from about 0.01 ppm to about 10,000 ppm, preferably from about 0.05 ppm to about 10 ppm and most preferably from about 0.1 ppm to about 1.0 ppm. The preferred compound is 1,3,6,8-pyrene tetrasulfonic acid, tetrasodium salt.
The fourth aspect of the instant claimed invention is a composition of matter comprising

The amount of 1,5-naphthalenedisulfonic acid or a known salt of 1,5-naphthalenedisulfonic acid present in the corrosive material is from about 0.01 ppm to about 10,000 ppm, preferably from about 0.05 ppm to about 10 ppm and most preferably from about 0.1 ppm to about 1.0 ppm. The preferred compound is 1,5-naphthalenedisulfonic acid, disodium salt.
The fifth aspect of the instant claimed invention is a composition of matter comprising

- a) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of isomers of anthracene disulfonic acid and salts thereof, and
- b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water and wherein dimethylformamide is about 100 wt. % dimethylformamide.

The amount of isomer of anthracene disulfonic acid and salts thereof present in the corrosive material is from about 0.01 ppm to about 10,000 ppm, preferably from about 0.05 ppm to about 10 ppm and most preferably from about 0.1 ppm to about 1.0 ppm. The preferred isomers of anthracene disulfonic acid are 1,5-anthracene disulfonic acid, magnesium salt, 1,5-anthracene disulfonic acid, sodium salt and 1,8-anthracene disulfonic acid sodium salt and mixtures thereof. The most preferred isomer of anthracene disulfonic acid is about a 2:1 mixture of 1,5-anthracene disulfonic acid, sodium salt and 1,8-anthracene disulfonic acid sodium salt.
The ability to trace a corrosive material is useful for the operation of many different industrial water systems.
The following examples are presented to be illustrative of the present invention and to teach one of ordinary skill how to make and use the invention. These examples are not intended to limit the invention or its protection in any way.

EXAMPLES

Sample Preparation:

Fluorescent tracer solutions (see Table 1) were prepared by adding a specified weighed amount of a stock solution of fluorescent tracer into a corrosion-resistant 250 mL polypropylene bottle. Corrosive liquid solution was added to the propylene bottle containing tracer solution to provide a total volume of 100 mL. The fluorescent tracer and corrosive liquid were mixed. The samples were stored at ambient temperature for a total of 59 days. Test samples were taken at defined intervals from each traced corrosive liquid solution (initial, 4 days and 59 days) and fluorescence level was measured.

TABLE 1


	Stock Solution	Amount	Test Solution
Fluorescent Tracer	Concentration*	Added	Concentration

1,5-naphthalenedisulfonic	130 ppm	0.31 gram	0.4 ppm
acid, disodium salt
1,3,6,8-pyrenetetrasulfonic	10 ppm	1.00 gram	0.1 ppm
acid, tetrasodium salt
fluorescein, monopotassium	0.3 ppm	3.33 gram	0.010 ppm
salt
1,5-anthracenedisulfonic	109 ppm	0.74 gram	0.8 ppm
acid, magnesium salt

*Tracer concentration expressed as acid equivalent form

Fluorometer Selection and Set-Up for Detection of Fluorescent Signal A SPEX fluorometer (Model FluoroMax-2) was used to measure the fluorescent signal and determine dosages of fluorescent tracers being tested in corrosive liquids. The fluorescent signal of each tracer was measured at the excitation and emission wavelengths listed in Table 2. A rectangular quartz cuvette (10 mm×3 mm, inner dimensions) was used to hold the sample. Each combination of fluorescent tracer and corrosive liquid was normalized to 100% in the “initial sample” (Table 3) which was measured within one hour after the tracer and corrosive liquid were mixed. In a few cases (Samples # 6, 16-19, and 21), the fluorescent tracer was not chemically stable with the corrosive liquid being tested and the fluorescent signal quickly decreased to virtually zero. In those cases, the “Initial Sample” was listed as having 0-1% fluorescence and that combination of tracer and corrosive fluid was judged as not acceptable. The fluorescence of the tracer and corrosive liquid solutions were tested again at 4 days and 59 elapsed time. The relative fluorescence of the samples measured at 4 days and 59 days are listed in Table 3. The fluorescence of tracers which change by less than or equal to +/−10% (% relative fluorescence range=90 to 110%, as compared to initial sample) on Day 59 are given an acceptable rating and are defined as being inert over long time periods in the corrosive liquid environment being tested. % relative fluorescence readings on Days 4 and 59 which are greater than 100% indicate an increase in % relative fluorescence, as compared to initial sample. % relative fluorescence readings on Days 4 and 59 which are less than 100% indicate an decrease in % relative fluorescence, as compared to initial sample.

TABLE 2


	Excitation	Emission
Fluorescent Tracer	Wavelength (nm)	Wavelength (nm)

1,5-naphthalenedisulfonic	290 nm	330 nm
acid, disodium salt
1,3,6,8-pyrenetetrasulfonic	365 nm	400 nm
acid, tetrasodium salt
fluorescein, monopotassium	486 nm	515 nm
salt
1,5-anthracenedisulfonic acid,	365 nm	415 nm
magnesium salt

TABLE 3


Relative Fluorescence over Time of Fluorescent
Tracer in Corrosive Liquid Solution

Relative Fluorescence

Sample #	Fluid Tested	Initial	4 days	59 days	Acceptable?*

Compound #1

1	Water{circumflex over ( )}	100	100	100	yes
2	Concentrated Hydrochloric Acid (˜37% aq. HCl)	100	97	95	yes
3	Concentrated Sulfuric Acid (98% acid)	100	74	0	no
4	Glacial Acetic Acid (˜100% acid)	>>100**	N/A	N/A	no
5	Concentrated Phosphoric Acid (˜85% H3PO4)	100	98	95	yes
6	Concentrated Sodium Hydroxide (50% NaOH){circumflex over ( )}	1	0	0	no
7	DMF (100% Dimethylformamide)	100	106	115	no

Compound #2

8	Water{circumflex over ( )}	100	100	100	yes
9	Concentrated Hydrochloric Acid (˜37% aq. HCl)	100	96	94	yes
10	Concentrated Sulfuric Acid (98% acid)	100	102	102	yes
11	Glacial Acetic Acid (˜100% acid)	100	102	102	yes
12	Concentrated Phosphoric Acid (˜85% H3PO4)	100	101	101	yes
13	Concentrated Sodium Hydroxide (50% NaOH){circumflex over ( )}	100	2	12	no
14	DMF (100% Dimethylformamide)	100	99	96	yes

Compound #3 These samples are kept in the dark to

avoid light degradation of the fluorescein molecule

15	Water{circumflex over ( )}	100	100	100	yes
16	Concentrated Hydrochloric Acid (˜37% aq. HCl)	0	0	0	no
17	Concentrated Sulfuric Acid (98% acid)	0	0	0	no
18	Glacial Acetic Acid (˜100% acid)	0	0	0	no
19	Concentrated Phosphoric Acid (˜85% H3PO4)	0	0	0	no
20	Concentrated Sodium Hydroxide (50% NaOH){circumflex over ( )}	100	13	2	no
21	DMF (100% Dimethylformamide)	0	0	0	no

1,5-anthracenedisulfonic acid, magnesium salt

22	Water{circumflex over ( )}	100	100	100	yes
23	Concentrated Hydrochloric Acid (˜37% aq. HCl)	100	97	92	yes
24	Concentrated Sulfuric Acid (98% acid)	100	53	15	no
25	Glacial Acetic Acid (˜100% acid)	100	70	3	no
26	Concentrated Phosphoric Acid (˜85% H3PO4)	100	100	95	yes
27	Concentrated Sodium Hydroxide (50% NaOH){circumflex over ( )}	100	2	0	no
28	DMF (100% Dimethylformamide)	100	98	95	yes

*Acceptable value range is 90-110, which is +/− 10% of the initial reference point (100%)
**Not acceptable due to very high background fluorescence
{circumflex over ( )}Comparative Example, not an Example of the invention

TABLE 4


Compilation of Final Results for Fluorescent Tracers in Corrosive Liquid Solutions

Fluorescence Results from Day 59 Sample

Fluid Tested (listed below)	CMPD #1	CMPD #2	CMPD #3	ADSA

Water{circumflex over ( )}	yes	yes	yes	yes
Concentrated HCl (˜37% aq. HCl)	yes	yes	no	yes
Concentrated H2SO4 (98% acid)	no	yes	no	no
Glacial Acetic Acid (˜100% acid)	no	yes	no	no
Concentrated Phosphoric Acid (˜85% H3PO4)	yes	yes	no	yes
Concentrated sodium hydroxide (50% NaOH){circumflex over ( )}	no	no	no	no
DMF (100% dimethylformamide)	no	yes	no	yes

{circumflex over ( )}Comparative Example, not an Example of the invention

No = not inert (results change by more than +/− 10% between initial and Day 59 results),

where the word “no” is used, the combination of fluorescent tracer and fluid tested is

not an example of the instant claimed invention.

Yes = inert (results change by less than +/− 10% between initial and Day 59 results)

CMPD #1 = COMPOUND #1 = 1,5-naphthalenedisulfonic acid, disodium salt

CMPD #2 = COMPOUND #2 = 1,3,6,8-pyrenetetrasulfonic acid, tetrasodium salt

CMPD #3 = COMPOUND #3 = fluorescein, monopotassium salt

ADSA = 1,5-anthracenedisulfonic acid, magnesium salt

Results:

Compound

Fluid Tested	#1	#2	#3	#4

Water{circumflex over ( )}	yes	yes	yes	yes
Concentrated HCl (˜37% aq. HCl)	yes	yes	no	yes
Concentrated H2SO4 (98% acid)	no	yes	no	no
Glacial Acetic Acid (˜100% acid)	no	yes	no	no
Concentrated Phosphoric Acid (˜85% H₃PO₄)	yes	yes	no	yes
Concentrated sodium hydroxide (50% NaOH){circumflex over ( )}	no	no	no	no
DMF (100% dimethylformamide)	no	yes	no	yes

No = not inert (results change by more than +/− 10% between initial and Day 59 results)

{circumflex over ( )}comparative example, not an example of the invention

#1 = 1,5-naphthalenedisulfonic acid, disodium salt available from Nalco

#2 = 1,3,6,8-pyrenetetrasulfonic acid, tetrasodium salt available from Nalco as

#3 = fluorescein, monopotassium salt available from Nalco

#4 = 1,5-anthracenedisulfonic acid, magnesium salt, available from Nalco

The present method has been described in an illustrative manner. Many modifications and variations are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

Claims

1. The method of using an inert fluorescent tracer in an industrial water system wherein the water of said industrial water system contains a certain amount of a corrosive material, comprising the steps of:

A) providing an industrial water system wherein the water of said industrial water system contains a certain amount of a corrosive material;

B) adding to the water of said industrial water system a treatment chemical wherein said treatment chemical includes an inert fluorescent tracer in a known proportion;

C) providing a fluorometer capable of detecting the fluorescent signal of said inert fluorescent tracer, wherein said fluorometer has a sample cell that corrosive materials can be placed in without rendering the sample cell unusable;

D) using said fluorometer to detect and measure the fluorescent signal of said fluorescent tracer in the water of said industrial water system;

E) using the detected and measured fluorescent signal to determine how much of the treatment chemical is present in the water of said industrial water system; and optionally;

F) adjusting the operating parameters of said industrial water system such that the amount of treatment chemical present is optimal for the operating conditions of said industrial water system.

2. The method of claim 1 in which said corrosive material is selected from the group consisting of concentrated HCl, Concentrated H₂SO₄, Glacial Acetic Acid, Concentrated H₃PO₄and dimethylformamide, wherein said concentrated HCl is at least about 37 wt. % HCl in water, said concentrated H₂SO₄is at least about 98 wt. % H₂SO₄in water, wherein said concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water; wherein said glacial acetic acid is at least about 100 wt. % acetic acid in water and wherein said dimethylformamide is about 100 wt. % dimethylformamide.

3. The method of claim 2, wherein when said corrosive material is concentrated HCl, said inert tracer is selected from the group consisting of

(a) 1,5-naphthalenedisulfonic acid and the known salts of 1,5-naphthalenedisulfonic acid,

(b) 1,3,6,8-pyrenetetrasulfonic acid, and the known salts of 1,3,6,8-pyrenetetrasulfonic acid, and

(c) isomers of anthracene disulfonic acid and salts thereof.

4. The method of claim 2, wherein when said corrosive material is concentrated H₂SO₄, said inert tracer is 1,3,6,8-pyrenetetrasulfonic acid, tetrasodium salt.

5. The method of claim 2, wherein when said corrosive material is concentrated glacial acetic acid said inert tracer is 1,3,6,8-pyrenetetrasulfonic acid, tetrasodium salt.

6. The method of claim 2, wherein when said corrosive material is concentrated H₃PO₄, said inert tracer is selected from the group consisting of

(b) 1,3,6,8-pyrenetetrasulfonic acid and the known salts of 1,3,6,8-pyrenetetrasulfonic acid, and

(c) isomers of anthracene disulfonic acid and salts thereof.

7. The method of claim 2, wherein when said corrosive material is dimethylformamide, said inert tracer is selected from the group consisting of 1,3,6,8-pyrenetetrasulfonic acid, the known salts of 1,3,6,8-pyrenetetrasulfonic acid, isomers of anthracene disulfonic acid and salts thereof.

8. A method of tracing a corrosive material, comprising the steps of:

(a) providing an industrial water system and a corrosive material that will be present in the water of the industrial water system;

(b) placing in said corrosive material an inert fluorescent tracer which has a detectable fluorescent signal when placed in said corrosive material, wherein said inert fluorescent tracer is added to said corrosive material in a known proportion;

(c) adding said corrosive material containing an inert fluorescent tracer to the water of said industrial water system;

(d) providing a fluorometer capable of detecting the fluorescent signal of said inert fluorescent tracer, wherein said fluorometer has a sample cell that corrosive materials can be placed in without rendering the sample cell unusable;

(e) using said fluorometer to detect and measure the fluorescent signal of said fluorescent tracer in the water of said industrial water system;

(f) using the detected and measured fluorescent signal to determine how much of the corrosive material is present in the water of said industrial water system; and optionally

(g) adjusting the operating parameters of said industrial water system such that the amount of corrosive material present is optimal for the operating conditions of said industrial water system.

9. A composition of matter comprising

a) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of 1,3,6,8-pyrene tetrasulfonic acid and the known salts of 1,3,6,8-pyrene tetrasulfonic acid.

b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl, concentrated H₂SO₄, glacial acetic acid, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, concentrated H₂SO₄is at least about 98 wt. % H₂SO₄in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water; wherein glacial acetic acid is at least about 100 wt. % acetic acid in water and wherein dimethylformamide is about 100 wt. % dimethylformamide.

10. The composition of claim 9 wherein the compound is 1,3,6,8-pyrenetetrasulfonic acid, tetrasodium salt.

11. A composition of matter comprising

a) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of 1,5-naphthalenedisulfonic acid and the known salts of 1,5-naphthalenedisulfonic acid, and

b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl and concentrated H₃PO₄; wherein concentrated HCl is at least about 37 wt. % HCl in water and wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water.

12. The composition of claim 11 wherein the compound is 1,5-naphthalenedisulfonic acid, disodium salt.

13. A composition of matter comprising

a) from about 0.01 ppm to about 10,000 ppm of a compound selected from the group consisting of isomers of anthracene disulfonic acid and salts thereof, and

b) a corrosive material, wherein said corrosive material is selected from the group consisting of concentrated HCl, concentrated H₃PO₄and dimethylformamide; wherein concentrated HCl is at least about 37 wt. % HCl in water, wherein concentrated H₃PO₄is at least about 85 wt. % H₃PO₄in water and wherein dimethylformamide is about 100 wt. % dimethylformamide.

14. The composition of claim 13 wherein the compound is about a 2:1 mixture of 1,5-anthracene disulfonic acid, disodium salt and 1,8-anthracene disulfonic acid, disodium salt.