The present invention relates to a process for the formation of an alcohol from an alkanoic acid, the steps of the process comprising: contacting a feed stream containing the alkanoic acid and hydrogen at an elevated temperature with a hydrogenating catalyst comprising from 3 to 25 wt. Two plates are installed across the conduit, one of them being fixed and the other being variable in angular position relative to the first. The detector means is tuned to only detect the signal transmitted by the transmitter means when the detector is located within a predetermined distance from the transmitter means. A further process for the production of one or more of linear phosphorous containing compounds is also described, which includes reacting a phosphorous containing compound, such as a phosphine, and a synthesis gas over a catalyst at a temperature of between 160\xb0 C.