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Hoffman, James S.

Publications and source records attributed to Hoffman, James S..

Amino acids react with carbon dioxide (CO2) and form nanofibers and nanoflowers

A method for capturing CO2 comprising dissolving at least one pure amino acid (AA) in water without the use of a catalyst for establishing protonation of an amino group of the amino acid, adding at least one base solution to the amino acid and water solution to deprotonate the protonated amino group of the amino acid and forming an amino acid-XOH—H2O wherein X is sodium or potassium, and subjecting CO2 to the amino acid-XOH—H2O to form new nanomaterials is provided. A regenerable nanofiber is disclosed comprising a NaHCO3 nanofiber, a KHCO3 nanofiber, or an amino acid nanofiber made from subjecting a CO2 gas to an amino acid aqueous solvent. Preferably, the amino acid aqueous solvent is one or more of a Gly-NaOH—H2O, an Ala-NaOH—H2O, a Phe-NaOH—H2O, a Gly-KOH—H2O, an Ala-KOH—H2O, and a Phe-KOH—H2O.

36 MATERIALS SCIENCE↗

Polymers of Intrinsic Microporosity Chemical Sorbents Utilizing Primary Amine Appendance Through Acid–Base and Hydrogen-Bonding Interactions

In this work, we introduce novel chemical sorbents based on polymers with intrinsic microporosity (PIMs). For the first time, alkylamines were incorporated in PIMs through an acid–base interaction to create a chemisorbent. The amine-appended PIMs not only showed a nearly four-fold enhancement in CO 2 loading capacity (36.4 cc/g at 0.15 bar and 298 K) and very high CO 2 /N 2 selectivity compared to neat PIM -1 but moreover proved to have stable performance when cycled between adsorption and desorption isotherms under both dry and humid conditions that are typical for postcombustion CO 2 capture.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗