of 70% alcohol, carried out by means of amalgam with a sodium content of 0.24% in a reaction column measuring 1 m. in the length, and 3 cm. According to the invention, organic and inorganic compounds particularly nitro-compounds are consequently reduced by means of an alkalimetal amalgam and a reagent which is decomposed by the amalgam while hydrogen is set free, by bringing the compound to be reduced, the amalgam and the decomposition reagent together in the presence of a substance or substances by which the decomposition in question is accelerated. From the top of the first column the emulsion passes over continuously into the lower part of the column 2 through the pipe I0. This browser does not support the video element. In this way, the reduction of nitrobenzene to hydrazobenzene may smoothly and continuously be carried out as an entirely continuous process in a carbon filled reaction column. Schools to Start the Course on Responsible Use of Social Media. By means of a pump 9 the reacting mixture can be circulated through a pipe 8. Download : Download high-res image (155KB)Download : Download full-size image. MP board exam 2021 class 10 & 12 syllabus reduced by 30%. In this way the theoretical quantity of amalgam was supplied in appr. Physics. The apparatus chiefly consists of two reaction columns, a long column I and a shorter one 2, each provided with a heating or cooling jacket. If, under .certain conditions, the final product should still contain azobenzene, its alcoholic solution, resultin after the crystallisation of the hydrazobenzene, may be reversed into one of the preceding columns. the sodium supplied is used. Benzidine is prepared from nitrobenzene by reduction in alkaline medium to hydrazobenzene (C 6 H 5 NHNHC 6 H 5), which is converted to benzidine by treatment with strong acid. G. (HALLIE' I I 2,486,358. A priori, it might be expected, therefore, that above a certain reaction velocity a measure by which a more rapid decomposition of the amalgam is effected would only result in the formation of hydrogen gas and lead to losses. By continuing you agree to the use of cookies. 7. CES CITED Ihe following references ,are .of record in the file of this patent: FO E GN P E Number Country Date 200,167 Great Britain -1 July 3, 1923 203,159 GreatBritain Sept. 3, 1923 105,706 Switzerland July 1, 1924 410,180 Germany Mar. after which the reduction velocity drops but nevertheless a complete reduction. 70% of alcohol, it is exposed to the action of a flow of sodium amalgam in a reaction tower filled up with lumps of graphite or coke. The lighter solution of azobenzene ascends through the second column and is further reduced by means of the amalgam supplied through the pipe 11, the inflowing quantity of amalgam being regulated in such a manner that the hydrazobenzene solution, continuously leaving through the pipe 12, is colourless. In the application of carbon none of these drawbacks is encountered. With carbon the reduction process proceeds quantitatively and rapidly without any hydrogen losses occurring. a function of the degree of reduction of the reacting mixture. In weakly acidic medium, aniline is obtained whereas in alkaline medium, various mono and di-nuclear reduction products (such as nitrosobenzene, phenylhydroxylamine, azoxybenzene, azobenzene and hydrazobenzene) are obtained. A method for the reduction of organic or inorganic substances by sodium amalgam, A method of preparing hydrodiazo benzene-like compounds, Continuous adiabatic process for the mononitration of benzene, Manufacturing method and apparatus of 4-fluoroethylene carbonate, Electrochemical reduction of benzene using a carbon anode, Mediated electrosynthesis with cerium (IV) in methanesulphonic acid, Electrochemical cell with bipolar electrodes, Metalation of Aryl Fluorides in Tetrahydrofuran, Process for the electrolytic production of a hydroxylamine nitrate solution by direct reduction of nitric acid, Electron transfer in reactions of ketones with organolithium reagents. Since only amalgam with a sodium content of appr. 1949. When iron is applied the amalgam is decomposed so quickly that throughout the process hydrogen losses will occur, caused by the development of gas, while the iron itself is slightly amalgamated, finally resulting in a sharp decrease of the activity as well as in the occurrence of mercury losses. Through a pipe 10 the reaction mixture continuously flows into the second column, which is also provided with a supply pipe 11 for amalgam, with discharge pipes for the hydrazobenzene solution 12, for dilute lye 13, for amalgam 14 and for the vapours and gases formed 15, while also here a cooler 16 is inserted in the latter pipe.