Capacitive deionization (CDI) is an electrochemical method that effectively removes various ionic substances, and it is widely applied in desalination, water treatment, and material purification. Since CDI is based on an electric field effect that drags substances from the solution, its applicability is limited to charged species. Substances such as silicates lose their ionic charge depending on the solution pH, which makes it difficult to remove them using CDI techniques. The current study aims to overcome these limitations by proposing a hybrid-CDI (HCDI) system. The proposed HCDI system combines the functions of pH adjustment and ion removal. At the cathode of the HCDI, OH^– is generated through water reduction via a Faradaic reaction, thus elevating the pH inside the system. In this high pH environment, silicates exist as ionic forms. These ionic silicates are then effectively separated through the membrane capacitive deionization (MCDI) configuration that is located at the anode. The experimental results confirmed that the HCDI system could effectively remove silicates, which are difficult to eliminate in conventional CDI and MCDI systems. This HCDI approach not only addresses the limitations of conventional CDI technologies but also expands the potential applications to the removal of pH-sensitive species like silicates.