Abstract: A compound having the following structure: wherein: R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 are independently selected from (i) hydrogen atom, (ii) hydrocarbon groups (R) containing 1-30 carbon atoms and optionally substituted with one or more fluorine atoms, (iii) —OR? groups, (iv) —NR?2 groups, (v) —C(O)R? groups, and (vi) halogen atoms, wherein R? groups are independently selected from R groups and hydrogen atoms, and wherein the R group optionally includes a C(O), ether, or amino linkage; Xm? is an anionic species with a magnitude of charge m, where m is an integer of at least 1; and n is a number, provided that n×m=1. Also described herein are methods for removing one or more oxyanions from a liquid source by use of the above compound or mono-pyridyl derivative thereof.

Abstract: A compound having the following structure: wherein: R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 are independently selected from (i) hydrogen atom (H), (ii) alkyl groups (R) containing 1-3 carbon atoms and optionally substituted with one or more fluorine atoms, (iii) —(CH2)n(OCH2CH2)mX groups, (iv) OR? groups, (v) NR?2 groups, (vi) NHC(O)R?, (vii) C(O)R? groups, (viii) halogen atoms, (ix) NO2 groups, and (x) CN groups, wherein R? groups are independently selected from hydrogen atom (H); alkyl groups (R) containing 1-3 carbon atoms; and groups of the formula —(CH2)n(OCH2CH2)mX, wherein n is 0 or an integer of 1-3, m is 0 or an integer of 1-12, and X is H, OH, OCH3, or OCH2CH3. Also described herein are methods for selectively capturing carbon dioxide (CO2) from a liquid source by use of the above compound.

Abstract: Method for removing toxic oxyanions (e.g., selenate) from an aqueous source as follows: (i) dissolving an oxyanion precipitating compound (OPC) in the aqueous source to result in precipitation of a salt containing sulfate, toxic oxyanion, and the OPC, wherein the sulfate in the aqueous source is in a molar concentration at least equal to the total molar concentration of the toxic oxyanion, and the OPC is included in the aqueous source in a molar concentration equal to or greater than the total molar concentration of sulfate and toxic oxyanion; and (ii) removing the precipitated salt from the aqueous source to result in a supernatant containing a substantially lower concentration of the toxic oxyanion compared to the aqueous source.

Abstract: A compound having the following structure: wherein: R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10 are independently selected from (i) hydrogen atom, (ii) hydrocarbon groups (R) containing 1-30 carbon atoms and optionally substituted with one or more fluorine atoms, (iii) —OR? groups, (iv) —NR?2 groups, (v) —C(O)R? groups, and (vi) halogen atoms, wherein R? groups are independently selected from R groups and hydrogen atoms, and wherein the R group optionally includes a C(O), ether, or amino linkage; Xm? is an anionic species with a magnitude of charge m, where m is an integer of at least 1; and n is a number, provided that n×m=1. Also described herein are methods for removing one or more oxyanions from a liquid source by use of the above compound or mono-pyridyl derivative thereof.