Performance and mechanisms of alkaline solid waste in CO2 mineralization and utilization.

CO2 mineral sequestration using alkaline solid waste (ASW) is a promising strategy for synergistically reducing CO2 emissions and reusing industrial waste. However, improvement the carbonation degree still remains challenges due to the sluggish leaching rate of Ca/Mg ion at low pH. To the issues, this study proposed an amine-mediated CO2 absorption and mineralization process with six common ASWs, as well an ecological utilization route of CO2-ASW productions. Experimental results indicated that calcium carbide slag (CS) had greater CO2 mineralization capacity (86.2 g-CO2/kg-CS) than other ASWs, while stirring rate and particle size played a more important role during CO2 capture. Amine-mediated CO2 capture was verified to be more excellent with steel slag (SS) as mineral medium. When the MEA concentration was increased to 2 mol/L, the extraction efficiency of Ca2+ was increased by 35 %, leaded to the CO2 removal efficiency significantly promoted from 49 % to 92 %. The characterization of structural morphology referred spherical aragonite or needle-bar calcite was dominant for the porous mineralization products (30.6 m2/g). High germination index of pea seed (112.1 % at a dose of 10 g/L) inferred the negligible toxicological effects of tiny MEA residue over SS mineralization products, after centrifugally washing treatment. Pea seeds cultivated with mineralized products after centrifugal washing can achieve a growth rate of about 4 mm/d. Overall, this work provides a feasible route to apply the porous CO2-ASWs production into water conservation in arid and sandy land.

Ethane-1,2-diaminium bis-(4-carb-oxy-2-propyl-1H-imidazole-5-carb-oxy-ate) monohydrate.

In the title hydrated molecular salt, C(2)H(10)N(2) (2+)·2C(8)H(9)N(2)O(4) (-)·H(2)O, an intra-molecular O-H⋯O hydrogen bond occurs in the anion, forming an S(7) ring. The -CO(2) and -CO(2)H groups make dihedral angles of 3.2 (2) and 2.0 (3)°, respectively, with the five-membered ring. In the crystal, N-H⋯O, N-H⋯N and O-H⋯O hydrogen bonds lead to the formation of a three-dimensional supra-molecular architecture. The methyl group in the anion is disordered over two sets of sites in a 0.716 (9):0.284 (9) ratio. The ethylenediamine cation is generated by symmetry and the water molecule lies on a twofold axis.