Electrochemical Co-Production of Ammonia and Biodegradable Polymer Monomer Glycolic Acid via the Co-Electrolysis of Nitrate Wastewater and Waste Plastic

Abstract

Electrochemical reformation of nitrate wastewater and poly(ethylene terephthalate) (PET) plastic waste into ammonia (NH 3 ) and fine chemicals is a sustainable strategy for waste resource utilization. Herein, a co-production system of ammonia and glycolic acid (GA, degradable polymer monomer) is constructed by coupling nitrate reduction and ethylene glycol (EG, in PET hydrolysate) oxidation. Low-crystalline CoOOH (LC-CoOOH/CF) and Pd nanothorns (Pd NTs/NF) grown in situ on the metal foam substrates are employed as cathode and anode, respectively. The high density of amorphous regions in LC-CoOOH/CF enables enhanced nitrate adsorption and provides abundant active sites, ultimately leading to an ammonia Faradic efficiency (FE) of 97.38 ± 1.0% at −0.25 V vs reversible hydrogen electrode (RHE). Meanwhile, the unique nanothorn morphology endows the Pd NTs/NF with a high-curvature tip, triggering a tip effect (TE) to promote the highly selective oxidation of EG to GA. Furthermore, in the two-electrode coupling system, the coproduction of NH 3 and GA is operated at a low energy consumption (onset voltage: 0.5 V), much lower than the traditional nitrate electrolysis process (1.4 V). This study provides a method for the resource utilization of nitrate wastewater and PET plastic waste to co-produce NH 3 and value-added chemicals.

Controlled boron incorporation tuned two-phase interfaces and Lewis acid sites in bismuth nanosheets for driving CO2 electroreduction to formate

“…5c, the C dl values for a/c -BiB NAs/CF (3.09 mF cm −2 ) and a -BiB NAs/CF (3.02 mF cm −2 ) are much higher than for the c -Bi NAs/CF (1.13 mF cm −2 ). Since C dl is expected to be linearly proportional to the ECSA of electrocatalysts, 63,64 these results suggest that the doping of B atoms into the Bi nanosheet structure brings about a larger ECSA and favors increasing the number of catalytic active sites. In the process of CO 2 RR electrocatalysis, the adsorption and desorption of the CO 2 molecule and intermediates are crucial to the performance of electrocatalysis.…”

Fe and Cu Double-Doped Co3O4 Nanorod with Abundant Oxygen Vacancies: A High-Rate Electrocatalyst for Tandem Electroreduction of Nitrate to Ammonia

“…Recently, as a promising alternative for catalytic NO 3 RR, earth-rich transition-metal oxides have been investigated . Among these transition-metal oxides, spinel-type oxides are of increasing interest due to their inherent properties including multivalent nature, flexible ion configuration, and relatively high electrical conductivity. , Co 3 O 4 has obvious advantages in catalytic applications due to its availability, stability, and promising activity, indicating that it is a potential electrode material for the electrochemical reduction of NO 3 – . – However, the production of NH 3 generated by Co 3 O 4 is relatively low due to the difficulty of the electrochemical reduction of NO 3 – to NO 2 – , which hinders the committed step of converting NO 3 – to NH 3 . , …”

Cu/2D-CuOx Nanocomposites with Abundant Oxygen Vacancy Defects for Enhancing Ammonia Selectivity of Electrocatalytic Nitrate Reduction

“…In recent years, a great deal of research work has been carried out on catalytic ammonia synthesis. Electrocatalysis ammonia synthesis, , thermalcatalytic ammonia synthesis at mild conditions, , and photocatalytic ammonia synthesis are all promising ways for ammonia production. Electrocatalytic NO 3 – RR involves the supply of free electrons through an applied potential to reduce NO 3 – into harmless byproducts .…”