IP Library Granted Patent US 7,811,517
Granted Patent B2
US 7,811,517 · App. 12/042,058 · Granted Oct 12, 2010

Method of tracing corrosive materials

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Quick Facts
Patent No.
US 7,811,517
App. No.
12/042,058
Granted
Oct 12, 2010
Kind
B2
Abstract

A method of using an inert fluorescent tracer in a system that contains liquids in contact with solid surfaces and wherein said system contains a corrosive environment, 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.

Claims (20)

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

a) providing a system that contains a liquid;

b) providing a corrosive material that contains one or more inert fluorescent tracers which has a detectable fluorescent signal in said system when placed in said corrosive material, wherein said inert fluorescent tracers are added to said corrosive material in a known proportion, and wherein said corrosive material is selected from the group consisting of concentrated HCl, concentrated H 2 SO 4 , glacial acetic acid, concentrated H 3 PO 4 and dimethylformamide;

c) adding said corrosive material containing said inert fluorescent tracers to a liquid of said system;

d) providing one or more fluorometers capable of detecting the fluorescent signal of said inert fluorescent tracers, wherein said fluorometers have a sample cell that corrosive materials can be placed in without rendering the sample cell unusable;

e) using said fluorometers to detect and measure the fluorescent signal of said fluorescent tracers in said system;

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

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

2. The method of claim 1 , wherein said concentrated HCl is at least about 37 wt. % HCl in water, said concentrated H 2 SO 4 is at least about 98 wt. % H 2 SO 4 in water, wherein said concentrated H 3 PO 4 is at least about 85 wt. % H 3 PO 4 in 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 1 , wherein when said corrosive material is concentrated HCl, said inert tracers are selected from the group consisting of

a) 1,5-napthalenedisulfonic acid and the known salts of 1,5-napthalenedisulfonic 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 1 , wherein when said corrosive material is concentrated H 2 SO 4 , said inert tracer is 1,3,6,8-pyrenetetrasulfonic acid, tetrasodium salt.

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

6. The method of claim 1 , wherein when said corrosive material is concentrated H 3 PO 4 , said inert tracer is selected from the group consisting of

a) 1,5-napthalenedisulfonic acid and the known salts of 1,5-napthalenedisulfonic 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.

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

Assignments (7)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 4, 2017
From: NALCO COMPANY
To: ECOLAB USA INC.
Reel/Frame 042147/0420 →
CHANGE OF NAME Recorded Feb 28, 2017
From: NALCO COMPANY
To: NALCO COMPANY LLC
Reel/Frame 041835/0903 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 28, 2017
From: NALCO COMPANY LLC; CALGON CORPORATION; CALGON LLC; ONDEO NALCO ENERGY SERVICES, L.P.
To: ECOLAB USA INC.
Reel/Frame 041836/0437 →
RELEASE OF SECURITY INTEREST Recorded Feb 24, 2017
From: BANK OF AMERICA, N.A.
To: NALCO COMPANY
Reel/Frame 041808/0713 →
RELEASE OF SECURITY INTEREST Recorded May 26, 2015
From: BANK OF AMERICA, N.A.
To: NALCO COMPANY
Reel/Frame 035771/0668 →
SECURITY AGREEMENT Recorded May 18, 2009
From: NALCO COMPANY; CALGON LLC; NALCO ONE SOURCE LLC; NALCO CROSSBOW WATER LLC
To: BANK OF AMERICA, N.A., AS COLLATERAL AGENT
Reel/Frame 022703/0001 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 4, 2008
From: HOOTS, JOHN E.; DAVIS, BARBARA H.
To: NALCO COMPANY
Reel/Frame 020597/0619 →