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Remaining Solid particles
are collected at the end of the experiment. For each batch
the solids are separated using a 100 micron screen. The two fractions (-100µm and
+100µm) are weighed and characterised by elemental analysis (ICP) and SEM.
From these analyses, we can define the following criteria:
Silicon consumption rate
(Si utilization) of the fractions from the first and second
day.
Catalyst content
in each of the fractions from the first and second day, which will
give the amount of catalyst and cocatalyst transport from activated to non-activated
silicon.
In this study, performances of the reactions in term of productivity and selectivity is
similar for all the experiments in day 1 (same experimental conditions), and is the
result of the two fractions and additives performances for day 2. Productivity and
selectivity from the very different situations of day 2 will not be systematically
commented.
The study will focus on analysis done on solids samples, and more specifically on the
fraction +100µm representative silicon activated by catalyst transfer.
Experimental Results
Impact of temperature on copper transport
In first series of experiments, fresh silicon added to the reactor on day 2 was mixed
with reacted contact mass at a fixed temperature under nitrogen over a period of 2h.
After 2 hours period, methyl chloride was fed to the reactor and temperature was
adjusted to standard MCS reaction conditions.
At the end of the experiment, the contact mass was sieved at 100µm; Upper and lower
fraction were weighed and analysed by ICP.
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