Methods and systems for the quantitative chemical speciation of heavy metals and other toxic pollutants

Inactive Publication Date: 2012-08-16
MCGILL UNIV
View PDF12 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0011]In yet another aspect, the invention relates to a method for modifying a MS apparatus in order to perform the method of the invention, such method comprising inactivating the surfaces contacting the sample analyte, such as flow tubes, inlet walls, and interior of MS. The method further comprise adding a concentration or collection interface as defined above, and reducing the dead volume inside the injector port of the MS apparatus.
[0012]In a further aspect the invention relates to a

Problems solved by technology

It is the one metal that is least effectively retained by emission controls, partly due to its high vapour pressure.
Vapour from liquid elemental mercury and methyl mercury is more easily absorbed than inorganic mercury salts and can therefore cause more harm.
Presently the current techniques provide information on elemental analysis and the chemical composition of mercury species cannot be det

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Methods and systems for the quantitative chemical speciation of heavy metals and other toxic pollutants
  • Methods and systems for the quantitative chemical speciation of heavy metals and other toxic pollutants
  • Methods and systems for the quantitative chemical speciation of heavy metals and other toxic pollutants

Examples

Experimental program
Comparison scheme
Effect test

example 1

Preparation of the System

[0046]a. Preparation of Gold Nanoparticle-coated Fiber and Trap

[0047]Single layer Au-nanoparticle surfaces are coated onto stainless-steel interface and / or a wire for mercury capture. The process begins by cleaning the stainless-steel wire with a 3:1 mixture of concentrated H2SO4 and 30% H2O2, both to remove trace organics and other contaminants and to increase the number of pendant oxygen atoms available for silanization on the surface. The cleaned wire was then immersed for two minutes in a solution containing 60 μL of 3-(aminopropyl)-trimethoxysilane (APTMS) dissolved in 15 mL of a 3:1 mix of 18.2 MΩ water and ethanol. After silanization, loose silanes were removed from the surface by rinsing with ethanol, and the wire / filter / trap was blown-dry with UHP N2 gas. The APTMS was allowed to cure at room temperature for several hours before continuing the SPME preparation.

[0048]Once the APTMS-covered wire had cured, it was immersed in a gold nanoparticle colloi...

example 2

Analyte Collection for Sample

[0064]a. Example of Collection Using a Sampling Flask as an Interface

[0065]Gold and / or sulfur nanoparticle-coated surfaces (e.g. Fe / Au) were preconditioned for several minutes under vacuum at a temperature of ca. 360° C. before insertion into a ˜2 L air sampling flask. The sampling flask, as well as all FEP tubing up-flow of the flask, was washed several times with 1M nitric acid and 18.2 MΩ water. Air was passed through the air sampling flask at ca. 18 L per minute for a total time of 14-19 hours. In one extraction, a 0.45 μm Teflon™ filter was attached at the sample line inlet to prevent particulate mercury from entering the sample line.

[0066]b. Analyte Pre-concentration from Air

[0067]A series of physical and physicochemical traps for the collection of measureable quantities of oxidized mercury from large volumes of air have been developed. For example, traps included pieces of 10 cm long 6 mm diameter glass tubing containing gold-microparticle-coated ...

example 3

Calibration and Analysis

[0071]a. APCI-MS Analysis of Mercury Species Extracted from Air

[0072]Mercuric halides collected onto gold nanoparticles-coated fibers and traps were desorbed directly into the source of an atmospheric pressure chemical ionization mass spectrometer (APCI-MS) for detection. APCI-MS analysis of mercury halides is performed in negative mode (i.e. detection of negative ions only). The APCI-MS inlet accommodates both the fiber and a N2 carrier gas that flows around the outer tubing of the fiber at a rate of 0.3-3 L / min. Initially, the inlet is kept isothermal at 50° C. while the fiber is exposed to the gas stream. No gases are observed to desorb from the fiber / trap at this temperature. When the instrument baseline is stable, the inlet is ramped to 360-375° C. over the course of several seconds. The HgCl2 and HgBr2-gold amalgams destabilize in the temperature range of 300-330° C., resulting in a peak whose area can be integrated for quantification similar to the chr...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

This invention relates to systems and methods for measuring quantitatively multiple species or heavy metals, including mercury, and other toxic pollutants. More specifically, the systems and methods of the invention allows for determination of the analytes even at very low concentration, through concentration on a collection interface, desorption and analysis by mass spectrometry. The invention also provides for a portable device or kit for modifying an existing mass spectrometer.

Description

FIELD OF THE INVENTION[0001]The invention relates generally to methods, systems and portable devices for measuring quantitatively multiple species of heavy metals, including mercury or other toxic pollutants in air, and in the aqueous phase, including water, molten snow / ice, and rain.BACKGROUND OF THE INVENTION[0002]Mercury is the top-identified contaminant in the environment and has been identified as a toxic agent by international advisory boards. It is the one metal that is least effectively retained by emission controls, partly due to its high vapour pressure. Once emitted, mercury may be deposited by wet and dry processes to environmental surfaces. In its vapour form, mercury can be carried long distances on wind currents, staying in the atmosphere for long periods of time. Mercury can change from one form to another in the environment (FIG. 1). For example, some types of bacteria and fungi can change mercury into its most toxic form, methyl mercury. Methyl mercury tends to be ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): H01J49/26G01J3/42G01N15/06G01N21/64
CPCG01N1/405H01J49/04G01N33/1813G01N15/06H01J49/0022H01J49/26
Inventor ARIYA, PARISA A.RAOFIE, FARHADDEEDS, DANIEL
Owner MCGILL UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap