Embodiments of the present disclosure generally relate to apparatus for solvent extraction of coal and to processes for solvent extraction of coal. In an embodiment, an apparatus for solvent extraction of coal is provided. The apparatus includes a plurality of stationary members coupled to a stationary shaft, each stationary member having a stationary member opening. The apparatus further includes a rotatable shaft extending through the plurality of stationary members. The apparatus further includes a plurality of rotatable members coupled to the rotatable shaft, each rotatable member paired with a stationary member, and each rotatable member has a rotatable member opening configured to rotate relative to the stationary member opening. The apparatus further includes a plurality of members for agitating materials passing through the apparatus, the members for agitating materials coupled to the rotatable shaft, each member for agitating materials positioned between the paired stationary members and rotatable members.

The present invention relates to a process for the selective extraction of a salt to be extracted from a brine to be treated containing the said salt to be extracted, characterized in that: the brine to be treated (S1) is sent to an initial extraction stirrer-mixer (1a) into which a liquid hydrophobic organic phase is also introduced, the said brine and the said liquid hydrophobic organic phase are mixed in the said initial extraction stirrer-mixer (1a), and the mixture is sent to an initial decanter-separator (1d, 1dc), in order to obtain: a brine from which salt to be extracted has been removed; and an organic phase loaded with salt to be extracted; the brine from which the salt to be extracted has been removed is recovered; the organic phase loaded with salt to be extracted is sent to an initial washing stirrer-mixer-decanter-centrifugal separator (5a, 5dc or 7a, 7dc), in order to obtain a purified organic phase loaded with salt to be extracted, which is sent to a so-called organic heat exchanger (1e) in which it is heated before being sent to a so-called initial regeneration column (1c; 2c), in which a countercurrent exchange is carried out with hot water at a higher temperature than that of the initial brine, in order to obtain: a water containing the salt to be extracted; and a regenerated organic phase, having lost the salt to be extracted; the regenerated organic phase is recycled to the initial extraction stirrer-mixer (1a).