Heterogeneous biochars from agriculture residues and coal fly ash for the removal of heavy metals from coking wastewater

摘要: While we have started down the path towards a global transition to green economy, as with most things began “low-hanging fruit,” such that increasingly difficult material and chemical conversions remain. Coking is one example; it unlikely steel production will away from using coking coal anytime in near future, wastewater remains environmental challenge. However, can develop greener methods materials treat waste. The present work demonstrates how wheat straw, an abundant agricultural residue, be co-pyrolyzed co-activated fly ash produce high surface area biochar. Coal has previously been shown promote devolatilization deoxygenation of pyrolyzed biofuels. This shows increases microporosity well aromaticity functional groups, while decreasing carbonyl but preserving or only slightly ketones carboxylic acids. CO2-activation 5 10 wt% straw blends yields heterogeneous biochars adsorption capacities upwards 170 mgmetal gchar−1, showing higher capacity uptake rates than 0 blends. four heavy metals ions (Ni2+, Co2+, Zn2+, Mn2+) was nature, cobalt preferentially adsorbing char surface. overall rate limited by initial rapid fill available sites.