Gooch

A Gooch perforated porcelain plate may also be used. 

Method 1. From ammonium chloroplatinate. Place 3 0 g. of ammonium chloroplatinate and 30 g. of A.R. sodium nitrate (1) in Pyrex beaker or porcelain casserole and heat gently at first until the rapid evolution of gas slackens, and then more strongly until a temperature of about 300° is reached. This operation occupies about 15 minutes, and there is no spattering. Maintain the fluid mass at 500-530° for 30 minutes, and allow the mixture to cool. Treat the sohd mass with 50 ml. of water. The brown precipitate of platinum oxide (PtOj.HjO) settles to the bottom. Wash it once or twice by decantation, filter througha hardened filter paper on a Gooch crucible, and wash on the filter until practically free from nitrates. Stop the washing process immediately the precipitate tends to become colloidal (2) traces of sodium nitrate do not affect the efficiency of the catalyst. Dry the oxide in a desiccator, and weigh out portions of the dried material as required. 

Purification of asbestos. Boil Gooch asbestos (tremolite, not chrysolite variety) with concentrated nitric acid, filter, wash free from acid, and dry at 100°. 

Fritted glass crucibles cannot withstand high temperatures and, therefore, should only be dried in an oven at temperatures below 200 °G. The glass fiber mats used in Gooch crucibles can be heated to a maximum temperature of approximately 500 °G. 

This adaptor consisted of two 24/40 joints connected with Gooch tubing. 

It is satisfactory to use the Super-Cel brand of kieselguhr supplied by Johns-Manville Company and asbestos of the type used in Gooch crucibles. Inclusion of these inert materials facilitates mixing and extraction of the product. 

Figure 4-2. Jaoketed batoh reaotor. (Source D. B. Gooch, Autoclaves Pressure—Temperature Reactions," Ind. Eng. Chem., 35, 927-946, 1943. Used with permission from the American Chemical Society.)...

Gooch, J.R. and Hounslow, M.J., 1996. Monte Carlo simulation of size-enlargement mechanisms in crystallization. American Institute of Chemical Engineers Journal, 42(7), 1864-1874. 

Wlien the top liquid is no longer opalescent but clear, the piecipitate is collected in a Gooch ciucible and diicd and w eighed as described on p. 26. 

Gooch tubing. Between additions of suitable portions of the solid, the tubing may be sharply bent to protect the solid from the reaction vapors (Fig. A3.4). 

Goochtiegel, m., Gooch scher Tiegel. Gooch crucible. 

Gooch, T. G. and Gregory, E. N., Br. Corros. J., Suppl. issue, Design of Protective Systems for Structural Steelwork, 48 (1968)... 

The liquid is filtered with suction through a Gooch crucible with a fixed porous plate (Note 1), and 100 cc. of water is added. The anthrone crystallizes at about io°. After being dried on a porous plate, it melts at about 153° (corr.). The yield is 80 g. (82.5 per cent of the theoretical amount). On rccrystal-lization from a 3 1 mixture (Note 2) of benzene and petroleum ether about 60 g. of anthrone melting at 154-155° (corr.) is obtained (62 per cent of the theoretical amount). 

Lithium aluminum hydride was obtained from Fluka AG or from Ventron Corporation. One convenient technique for the addition is to weigh the reagent into an Erlenmeyer flask, which is then connected to the reaction flask by a short piece of Gooch tubing. In this way the solid can be added in portions without exposing it to the atmosphere. 

If such a funnel is not available, an Erlenmeyer flask connected to the reaction flask by a length of thin-walled rubber tubing (Gooch tubing) may be substituted. In this case, the reaction mixture must not be stirred so vigorously that liquid is splashed up into the neck of the flask, which would cause aluminum chloride to cake there and prevent it from falling into the flask. 

A convenient technique is to add the methoxide from an Erlcn-meyer flask, connected to the previously stoppered neck of the reaction flask by a piece of flexible rubber tubing (Gooch tubing). 

B. l-Bromo-2-fluorobenzene. Cautionl This step should be carried outm a hood because the PFS evolved on thermal decomposition of the diazonium salt is poisonous. The apparatus consists of a 1-1., three-necked, round-bottomed flask equipped with a thermometer, a condenser, a magnetic stirrer (optional), and a 250-ml. Erlenmeyer flask that is attached by means of a short rubber Gooch connecting tube. The dry powdered hexafluorophosphate salt is placed in the Erlenmeyer flask, and 300 ml. of heavy mineral oil is placed in the round-bottomed flask. The mineral oil is heated to 165-170° by means of an oil bath or electric heating mantle and maintained at this temperature while the salt is added rapidly in portions over a period of 30 minutes. The flask is cooled rapidly to room temperature, the side flask is removed, and 400 ml. of 10% aqueous sodium carbonate is added slowly through the condenser. The mixture is steam-distilled until no more oil is visible in the distillate. 

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