Integrated thermochemical process for the combined recovery of organic carbon and inorganic raw materials from residual matrices comprising organic material and an initial quantity and composition of ash of inorganic materials with a percentage by weight of initial ash (Ain), comprising the following steps feeding a quantity of residual matrix, treatment by pyrolysis of the fed residual matrix actuated in a pyrolysis reactor by thermochemical degradation at pyrolysis temperatures maintained within a process value range between a lower value (T PL) of 400°C and an upper value (T PH) of 550°C with heating speeds not exceeding 40°C/minute and with a residence time between 30min and 2h, preferably between 30min and 1h30min, until obtaining a solid char containing said inorganic raw materials, cooling and grinding of the solid char from pyrolysis, mixing the ground char with water and obtaining a water-char mixture, hot leaching in one or more steps of said mixture of water and char at leaching temperatures by further mixing with a dosed quantity of leaching reagents and obtaining a leaching mixture, separating said leaching mixture into a solid phase containing leached char and a liquid phase containing inorganic leaching liquid, characterized in that the process include a preliminary step of composition analysis of said residual matrices, in said one or more steps of hot leaching a water-char ratio between min 4:1 and 20:1 by weight is processed, the leaching temperature of said mixture of water and char is maintained within a process value range between 50°C and 90°C said dosed quantity of leaching reagents comprise HNO3 alone or in combination with H2SO4, the dosed quantity of leaching reagents (R L) is comprised between a higher relative value of 70% and a lower relative value of 40% by weight with respect to the processed biochar, wherein the temperature of said pyrolysis step, the temperature of said leaching step and the quantity and composition of said mixed leaching reagents are adjusted based on a threshold value (Ainx) of the percentage by weight of initial ash (Ain) of the initial quantity and composition of ash present in the treated residual matrix and in combination with each other said threshold value (Ainx) of the percentage by weight of initial ash (Ain) is a percentage by weight lower than 25% on dry basis of said residual matrices. feeding a quantity of residual matrix, treatment by pyrolysis of the fed residual matrix actuated in a pyrolysis reactor by thermochemical degradation at pyrolysis temperatures maintained within a process value range between a lower value (T PL) of 400°C and an upper value (T PH) of 550°C with heating speeds not exceeding 40°C/minute and with a residence time between 30min and 2h, preferably between 30min and 1h30min, until obtaining a solid char containing said inorganic raw materials, cooling and grinding of the solid char from pyrolysis, mixing the ground char with water and obtaining a water-char mixture, hot leaching in one or more steps of said mixture of water and char at leaching temperatures by further mixing with a dosed quantity of leaching reagents and obtaining a leaching mixture, separating said leaching mixture into a solid phase containing leached char and a liquid phase containing inorganic leaching liquid, characterized in that the process include a preliminary step of composition analysis of said residual matrices, in said one or more steps of hot leaching a water-char ratio between min 4:1 and 20:1 by weight is processed, the leaching temperature of said mixture of water and char is maintained within a process value range between 50°C and 90°C said dosed quantity of leaching reagents comprise HNO3 alone or in combination with H2SO4, the dosed quantity of leaching reagents (R L) is comprised between a higher relative value of 70% and a lower relative value of 40% by weight with respect to the processed biochar, wherein the temperature of said pyrolysis step, the temperature of said leaching step and the quantity and composition of said mixed leaching reagents are adjusted based on a threshold value (Ainx) of the percentage by weight of initial ash (Ain) of the initial quantity and composition of ash present in the treated residual matrix and in combination with each other said threshold value (Ainx) of the percentage by weight of initial ash (Ain) is a percentage by weight lower than 25% on dry basis of said residual matrices.