Abstract: A washing device includes executors for executing a normal washing step and a reverse washing step before executing a plate opening step and a cake peeling step. The normal washing step is a step for supplying a washing water to a filter chamber, allowing the washing water to pass through a cake, and then discharging the washing water from filtrate discharge outlets. The reverse washing step is a step for supplying a washing water from the filtrate discharge outlet(s) to the filter chamber, allowing the washing water to pass through the cake, and then discharging the washing water from the filtrate discharge outlet(s) which are different from the filtrate discharge outlet(s) from which the washing water is supplied. The thickness of the electrode catalyst precursor-containing cake at the time of the injection step is adjusted to that of a range that has been previously and experimentally determined.

Abstract: Provided are an electrode catalyst production system and production method omitting transferring an electrode catalyst precursor, and shortening a drying time thereof. The system has an electrode catalyst precursor production device, a washing device and a drying device. The drying device includes executors for executing: an introduction step for introducing an electrode catalyst precursor into a container main body; a drying processing step for drying the precursor by heating and depressurizing the container main body, and stirring and mixing the precursor with a stirring blade; a cooling step for cooling the precursor by cooling and depressurizing the container main body, and stirring and mixing the precursor with the stirring blade; a slow oxidation step for performing a slow oxidation treatment on the precursor by supplying air to the container main body; and a retrieving step for retrieving the precursor inside the container main body.