Running the experiments We observed the effect of changing temperature, pressure/flowrate/residence time, amount of hydrogen, and solvent-reactant ratio on the product distribution. In all cases, the HPLC flowrate was 8 times that of the per-syringe flowrate. Some of the experiments were run at three different temperatures; at 30oC, 40oC, and 50oC, all at the base flowrate of 0.100 ml/min for each syringe, 12.14:1 volume for EtOH to o-nitroanisole ratio, and with a 3:1 molar ratio of H2 to o-nitroanisole. Some of the runs varied the molar ratio of hydrogen to o-nitroanisole from 3:1 (base case from stoichiometry, see Rxns 1 & 2) to 3:2, and to 6:1. The borohydride solution was made twice more concentrated and twice more dilute than the base case value. All runs were at 30oC, with a 12.14:1 by volume ratio of EtOH to o-nitroanisole ratio and 0.100ml/min per syringe. We varied ethanol to o-nitroanisole volume ratio from 12.14:1 (base case) to 15:1, to 5:1. The other variables were constant at 0.100 ml/min for the syringe flowrates, 30oC for the temperature, and 3:1 for the molar ratio of H2 to o-nitroanisole. We could not vary pressure and flowrate independently. The liquid residence time was varied indirectly; it was a function of liquid and hydrogen flowrates. We did, however, vary the syringe flowrates between 0.05 ml/min and 0.35 ml/min (per syringe), at 0.05ml/min intervals. The other variables were 30oC for the temperature, 12.14:1 v/v for EtOH to o-nitroanisole ratio, and 3:1 for the molar ratio of H2 to o-nitroanisole.
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