Typical supplies for VGA 77 Vapor Generation Accessory used with Agilent flame AA Spectrometers.

• The T-shaped open ended quartz absorption cell is used with the VGA 77 when determining hydride forming elements
• The small internal volume provides more uniform heating and more efficient atomization
• The closed, flow through cell provides better precision and sensitivity for cold vapor mercury determinations, and the end-mounted entry and exit ports facilitate collection of mercury vapors to comply with local discharge laws
• The gas-liquid separator for the VGA 77 facilitates the release of gas from the liquid mix, while inhibiting the formation of large bubbles. The small volume above the liquid helps achieve steady state conditions quickly
• The hydride module for the VGA-77 incorporates the plumbing manifold and the gas-liquid separator, and is interchangeable
• A separate hydride module should be used exclusively for Hg determinations to reduce cross contamination
• The hydride module is easily removed to enable change-over between determinations of hydride forming elements and mercury. It also incorporates space to hold the sample and reagent bottles
• Generation of the volatile metal hydrides use sodium borohydride as a reducing agent

The Agilent fully automated modular VGA 77 vapor generation accessory is used with Agilent flame AA systems to. enables rapid trace level determinations of mercury and other hydride-forming elements at parts-per-billion (μg/L) concentrations using the vapor or hydride generation technique. The VGA 77 offers the convenience of flame AA determinations, unmatched precision at ppb levels, and ease-of-use from the continuous flow operation.

The entire plumbing assembly is integrated into a separate hydride module, which can be simply exchanged when switching between elements. This reduces change-over times and eliminates cross-contamination from by the conflicting chemistries required for each element.