Optimization, DSC experiments

The optimal activation temperature of zeolites in the range 300-600°C was determined in preliminary experiments. The temperature 500°C was selected for all catalysts but for H-MFI-28 (400°C). DSC and TG analyses show that at 500°C, NH4+ forms of zeolites are totally converted into H-MOR-20 and H-FER-20, respectively. Table 2 shows alcohol conversion (XR0H), selectivity to ether (SROr), to olefin (Soiefm) and branched ethers (SrOR>), and ether yield (YROr) at 180°C after 6 h reaction course. 

However, it is a misimderstanding that one can obtain data from combined experiments that can compete with that obtained from independently performed and optimized experiments. Especially the thermodynamic results are often more qualitative than quantitative. The rationale behind combining experiments is that the thermodynamic data obtained with, for instance, an on-line dsc will still show the strong features. The correlation of specific thermodynamic features with time frames of the scattering data enables correlation with an independently obtained high quahty dsc trace. In such a case the on-line dsc acts as an accurate thermometer. 

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