Glass balls, catalyst

Combustion experiments were performed in a continues packed bed reactor. The reactor consisted of a stainless steel cylinder of 400 mm length and 9 mm internal diameter. Two grams of catalyst, crushed and sieved to 250-355 pm, were placed in the middle part of the reactor, whilst the upper and lower parts were filled with glass balls (1mm). The reactor was placed inside an electric furnace, temperature being controlled by a PID controller (Honeywell) connected to a thermocouple placed inside the reactor, which monitored the reaction temperature. The system was provided with 5 additional thermocouples that measured the reactor wall temperature at different positions. 

Catalysts were obtained by pressing powders imo tablets and gently breaking the tablet. The fraction between 500 and 800 micrometers was used for the catalytic tests. The catalytic tests were carried out in convetnional fixed bed reactors at atmospheric pressure. Catalyst was deposited between two layers of glass balls in a pyrex U-iube of 8 mm internal diameter. 

The procedures for the preparation of thionyl tetrafluoride and pentafluorosulfur hypofluorite are essentially the same, with one important difference the use of a catalyst. The apparatus employed in the preparations consists of several Monel pressure vessels (which have been prefluorinated at 150-200 ), a standard glass vacuum line equipped with several large calibrated storage bulbs (1- or 2-1.), a partial fractionation train, and several ball-joint connections on the main manifold. All the joints and stopcocks on the vacuum line are lubricated with Kel-F-90t grease, and all mercury manometers are covered with Kel-F-10 oil,t which has been well outgassed. The vacuum line is connected to a fluorine metering system and a water... 

Activities were measured in all-glass, vertical, tubular reactors with Alundum balls in the preheat section. A metal-free reactor was used because our earlier work had shown that type 316 stainless steel reactors converted 20-30% of the NO to NH3 in the absence of a catalyst there was no background conversion with glass. 

The filler process has been used for the preparation of open porous glass carrier balls, such as Siran [452], and also to produce complex open porous glass and glassceramic carrier bodies [466]. They are used in biotechnology for storage, conduction and distribution of liquids and in filtration and separation processes and also as catalyst support material. 

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