Hydrogen production from the tannery wastewater treatment by using agriculture supports membrane/adsorbents electrochemical system

The tannery is one of the oldest and most popular industries in the world. It is also characterized as pollutants generated industries which discharge toxic chemical output effluents to the environment. The process of tannery included a wide variety of chemical and inorganic constituents. This work focused on the removal of Chromium heavy metals as well as producing clean energy from the treatment of tannery wastewater. Accordingly, the analysis result on the input effluents appeared to have a brown color with a very high COD value, a high concentration of Chromium heavy metals as well as other organic compounds. After collected from the source, the effluents were settling and applied a simple subsequent filtration with lab scale cloth filter, the filtered effluents then were treated in an electrochemical system. Throughout many experiments, we introduce an electrochemical system with 5 × 5 cm electrodes (Platinum coated panel anode and carbon fiber cloth cathode), the low input voltage (10 V), easy setup and the support of separator membrane/adsorbents placed in the middle of the system to enhance the removal rates of heavy metals. It was found that the performance of the electrochemical system is under the influence of various factors such as temperature, pH value, adsorbents dose, and apply voltage. During 48 h of treatment, almost 80% of Chromium metals were treated by means of adsorption and electrical reduction process. The generation rate of hydrogen gases during the electrolysis process was also notable (45–65 cc/min). Furthermore, the adsorbent materials were still intact and seem to be ready for a longer run. The study also observed the adsorbent membrane of bagasse and straw showed their best removal efficiencies over other candidates. In that manner, we successfully provide an effective method for heavy metals removal and also capable of generating clean energy. The analysis results clarify that most of the parameters of the physical and chemical result were found well below the prescribed permissible limits of discharged effluents follows the standard of industrial waste management in Vietnam.