Breakthrough of Carbon-Ash Recalcitrance in Hydrochar via Molten Carbonate:Engineering Mineral-Rich Biowaste Toward Sustainable Platform Carbon Materials

The function-led design of porous hydrochar from mineral-rich biowaste for environmental applications inevitably suffers from carbon-ash recalcitrance.However,a method to alter the original carbon skeleton with ash remains elusive and hinders the availability of hydrochar.Herein,we propose a facile strategy for breaking the rigid structure of carbon-ash coupled hydrochar using phase-tunable molten carbonates.A case system was designed in which livestock manure and NaHCO3 were used to prepare the activated hydrochar,and NH3 served as the target contaminant.Due to the redox effect,we found that organic fractions significantly advanced the melting temperature of Na2CO3 below 800℃.The Na species steadily broke the carbon-ash interaction as the thermal intensity increased and transformed inorganic constituents to facilitate ash dissolution,rebuilding the hydrochar skeleton with abundant hierarchical channels and active defect edges.The surface polarity and mesopore distribution collectively governed the five cycles NH3 adsorption attenuation process.Manure hydrochar delivered favorable potential for application with a maximum overall adsorption capacity of 100.49 mg·g^(-1).Integrated spectroscopic characterization and theoretical computations revealed that incorporating NH3 on the carbon surface could transfer electrons to chemisorbed oxygen,which promoted the oxidation of pyridine-N during adsorption.This work offers deep insight into the structure function correlation of hydrochar and inspires a more rational design of engineered hydrochar from high-ash biowaste.

Renewable biomass reinvigorates sustainable water-energy nexus

The water-energy nexus has garnered worldwide interest.Current dual-functional research aimed at coproducing freshwater and electricity faces significant challenges,including sub-optimal capacities("1+1<2"),poor inter-functional coordination,high carbon footprints,and large costs.Mainstream water-toelectricity conversions are often compromised owing to functionality separation and erratic gradients.Herein,we present a sustainable strategy based on renewable biomass that addresses these issues by jointly achieving competitive solar-evaporative desalination and robust clean electricity generation.Using hydrothermally activated basswood,our solar desalination exceeded the 100% efficiency bottleneck even under reduced solar illumination.Through simple size-tuning,we achieved a high evaporation rate of 3.56 kg h^(-1)m^(-2)and an efficiency of 149.1%,representing 128%-251% of recent values without sophisticated surface engineering.By incorporating an electron-ion nexus with interfacial Faradaic electron circulation and co-ion-predominated micro-tunnel hydrodynamic flow,we leveraged free energy from evaporation to generate long-term electricity(0.38 W m^(-3)for over 14 d),approximately 322% of peer performance levels.This inter-functional nexus strengthened dual functionalities and validated general engineering practices.Our presented strategy holds significant promise for global human–society–environment sustainability.

LIVESTOCK AND POULTRY MANURE MANAGEMENT FROM THE PERSPECTIVE OF CARBON NEUTRALITY IN CHINA

The rapid growth of the livestock and poultry production in China has led to a rise in manure generation,which contributes to the emissions of GHGs(greenhouse gases including CH_(4),N_(2)O and CO_(2))and other harmful gases(NH_(3),H_(2)S).Reducing and managing carbon emissions has become a critical global environmental imperative due to the adverse impacts of GHGs.Unlike previous reviews that focused on resource recovery,this work provides an unique insight of transformation from resource-oriented manure treatment to integration of resource recovery with pollution reduction,carbon accounting and trading,focusing on the sustainable development of manure management system.Considering the importance of accounting methodologies for carbon emission and trading system toward carbon neutrality society,suggestions and strategies including attaching high importance to the development of more accuracy accounting methodologies and more practical GHG emission reduction methodologies are given in this paper.This work directs the establishment of carbon reduction methodologies and the formulation of governmental policies for livestock and poultry manure management system in China.