<PICT:0486492/III/1> In processes for the production of valuable hydrocarbons by the catalytic hydrogenation of carbonaceous material, in which the reaction temperature is controlled by the introduction of cooling agents into the reaction space, at least two-thirds of the cooling agent is introduced into the first half of the reaction space (relative to the direction of flow of the reagents) and the residual amount is introduced into the second half of the reaction space. Preferably 50-85 per cent of the total amount of cooling agents is introduced into the first third of the reaction space, and at least twice as many points for the introduction of cooling agent are provided in the first third as in the second third of the space. The reaction space may consist of a plurality of high-pressure vessels connected in series, and indirect cooling may also be provided. The cooling agents may be introduced through insulated tubes having openings in the forms of holes, nozzles, &c. Cooling agents specified include hydrogen, nitrogen, methane, oils, oily coal pastes and mixtures thereof, and may amount in the cases of gases to 10000-12000 cubic metres per hour with a through-put of 5000 litres of middle oil and 20,000 cubic metres of hydrogenating gas. With indirect cooling the tubes connecting the reaction vessels may be cooled and may be provided with ribs &c. facilitating heat transfer. The reaction temperature may be controlled to give a step-by-step increase of temperature so that there may be a difference of 10-100 DEG C. in the temperature of the reagents at the point of entry and exit of the reactor. The reaction conditions and the catalysts specified are those usually employed in catalytic hydrogenation reactions. Initial materials with fresh and recycle hydrogenating gases introduced through line 1 are fed through a heat exchanger 2 and a gas-heated preheater 3 into a series of reaction vessels 4, 5, 6 filled with catalyst. Cooling gas is introduced through a pipe 7 feeding tubes 8, 9, 10. The reaction products pass through line 11, heat exchanger 2 and cooler 13 to a stripping vessel 14 from which recycle gas is led off through line 15 and liquid reaction products through line 16. Brown-coal tar is preheated with hydrogen under 250 atmos. to 300 DEG C. and led through three reaction vessels. 2000 Cubic metres of hydrogen per ton of tar are employed, half being introduced with the tar while the other half is used as cooling gas, of which 77 per cent is introduced through eleven tubes into the first reactor, 20 per cent through three tubes into the second reactor, and 3 per cent through two tubes into the third reactor. The temperature of the reacting materials increases gradually up to 350 DEG C. Specifications 389,560 and 484,127 are referred to.ALSO:In processes for the production of cyclic hydrocarbons by the catalytic hydrogenation of carbonaceous material, as well as the conversion of cresol to phenol and phenol to cyclohexanol, in which the reaction temperature is controlled by the introduction of cooling agents into the reaction space, at least two-thirds of the cooling agent is introduced into the first half of the reaction space (relative to the direction of flow of the reagents) and the residual amount is introduced into the second half of the reaction space. Preferably 50-58 per cent of the total amount of cooling agents is introduced into the first third of the reaction space, and at least twice as many points for the introduction of cooling agent are provided in <PICT:0486492/IV/1> the first third as in the second third of the space. The reaction space may consist of a plurality of high-pressure vessels connected in series, and indirect cooling may also be provided. The cooling agents may be introduced through insulated tubes having openings in the forms of holes, nozzles, &c. Cooling agents specified include hydrogen, nitrogen, methane, oils, oily coal pastes and mixtures thereof, and may amount in the cases of gases to 10,000-12,000 cubic metres per hour with a throughput of 5000 litres of middle oil and 20,000 cubic metres of hydrogenating gas. With indirect cooling the tubes connecting the reaction vessels may be cooled and may be provided with ribs &c. facilitating heat transfer. The reaction temperature may be controlled to give a step-by-step increase of temperature so that there may be a difference of 10-100 DEG C. in the temperature of the reagents at the point of entry and exit of the reactor. The reaction conditions and the catalysts specified are those usually employed in catalytic hydrogenation reactions. Initial materials with fresh and recycle hydrogenating gases introduced through line 1 are fed through a heat-exchanger 2 and a gas-heated preheater 3 into a series of reaction vessels 4, 5, 6, filled with catalyst. Cooling gas is introduced through a pipe 7, feeding tubes 8, 9, 10. The reaction products pass through line 11, heat-exchanger 2 and cooler 13 to a stripping vessel 14 from which recycle gas is led off through line 15 and liquid reaction products through line 16. Brown-coal tar is preheated with hydrogen under 250 atmos. to 300 DEG C. and led through three reaction vessels. 2000 Cubic metres of hydrogen per ton of tar are employed, half being introduced with the tar while the other half is used as a cooling gas of which 77 per cent is introduced through eleven tubes into the first reactor, 20 per cent through three tubes into the second reactor, and 3 per cent through two tubes into the third reactor. The temperature of the reacting materials increases gradually up to 350 DEG C. Specifications 389,560 and 484,127, [both in Group III], are referred to.