Materials of construction effects

1 Materials of Construction Effects Class-lined Stainless Steel Tubing 

For the Tracer 4 curve, the flat top occurred from approximately 122 to 162 pL. Surprisingly, this volume was not near the geometrically calculated 42.2-65.7 pL volume. The 40 pL width of the flat top was in the range of the sum of the two inj ector volumes, approximately 60 pL. H owever, the full width at half maximum,  

If an absorption phenomenon is occurring, changing the materials of construction of the wetted surfaces could impact the results. The best reactor results (in which the reactor volume based on the tracer analysis most closely matches the geometrically calculated reactor volume) were attained with stainless steel materials of constmction. The injector loops, tubing from the injectors to the mixing tee, and the reactor were all changed to stainless steel materials of construction of equivalent volumes. The flat top experiments were repeated for this configuration Fig. 13.10 shows the results. 

As shown, the stainless steel system gave the maximum concentration from approximately 50 to 94 pL. This was much closer to the geometrically calculated 

2 pL to 65.7 pL, although it was still slightly larger than expected. This experiment conclusively demonstrated tliat materials of construction impact the lag time, supporting the absorption hypothesis. Integration of the two curves in Fig. 13.10 gives 159% and 114%, respectively, of the mass of Tracers 4 and 

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