In the proposed Electron-Ion Collider (EIC) experiments, particle identification (PID) of the final state hadrons in the semi-inclusive deep inelastic scattering allows the measurement of flavor-dependent gluon and quark distributions inside nucleons and nuclei. The EIC PID consortium (eRD14 Collaboration) has been formed for identifying and developing PID detectors using ring imaging Cherenkov (RICH) and the ultra-fast time-of-flight (TOF) techniques for the EIC experiments with broad kinematics coverage. A modular ring imaging Cherenkov (mRICH) detector has been designed for particle identification in the momentum coverage from 3 GeV/c to 10 GeV/c. The mRICH detector consists of an aerogel radiator block, a Fresnel lens, a mirror-wall and a photosensor plane. The first prototype of this detector was successfully tested at Fermi National Accelerator Laboratory in April 2016 for verifying the detector working principles. This talk will highlight the first mRICH beam test results and show the preliminary results from the second beam test in late June of 2018. An implementation of the mRICH detector array in the Forward Angle sPHENIX spectrometer at BNL will also be described in this talk.