Abstract: This disclosure is directed to devices for the separation of mixtures of fluid phases. In some aspects of the disclosure, the separation device comprises an angled capillary cell. In other aspects, the separation device comprises a plurality of angled capillary cells operating in parallel. In some aspects of the disclosure, the separation device may be monolithically formed by an additive manufacturing process, such as three-dimensional printing. In some aspects of the disclosure, the separation device may function independently of gravitational direction, and without the use of filters.