automation of analysis. some advantages of automation: some applications: - quality control -...
TRANSCRIPT
AUTOMATION
AUTOMATION
OF ANALYSIS
OF ANALYSIS
Some Advantages of automation:
Some applications:
- quality control
- process control
- environmental monitoring
Autotitrator
Titrations were of the first automated analytical techniques
Schematic representation of an automated colorimetric analysis
Autosamplers
Samplers:
Peristaltic pumps Syringe pump
Pumps:
Operates by means of rotating bars attached to a chain drive which compresses the plastic tubes to drive the liquid forward.
Automated determination of magnesium in urine using DAB (o,o’-dihydroxyazobenzene)
FLOW INJECTION ANALYSIS (FIA)
Involves injecting a liquid sample into a carrier stream which contains all chemicals necessary of the analysis.
The stream then flows through the detector.
The stream is unsegmented by air bubbles, thus dispersion of the sample occurs by both:
CONVECTIVE TRANSPORT DIFFUSIONAL TRANSPORT
Due to solution flow
Parabolic velocity profile in direction of flow
Due to concentration gradient
Radial diffusion
Block diagram of a flow injection spectrophotometric monitor for the determination of nitrate in river water
Selection valve
Injection valves
Valves: Load sample loop:
Flow through:
Results for continuous flow analysis of ethanol in beverages
CONSTANT MONITORING
Generally difficult to analyse within a process stream.
Often divert some of the steam and introduce a sampling loop.
The analysis could act as a feedback for optimising control of the process.
Submersible UV-Vis spectrometer
Schematic diagram of an analyser/controller for an acid catalysed reaction
ROBOTICS
Used when large numbers of samples have to be routinely processed before measurement.
In this country robotics is currently mainly used in the fire assay for gold and PGM’s
Manual Robotic
The pouring process:
Robotic lab