In alternative aspects, the invention provides processes for cyclic electrochemical adsorption of aqueous contaminants using nanocomposites of graphene with tin oxide or antimony doped tin oxide.

A porous sorbent ceramic product includes a three-dimensional structure having an electrically conductive ceramic material, wherein the conductive ceramic material has an open cell structure with a plurality of intra-material pores, a sorbent additive primarily present in the intra-material pores of the conductive ceramic material for adsorption of a gas, and at least two electrodes in electrical communication with the conductive ceramic material.

The instant disclosure sets forth a process for re-activating a mineral residue. The process includes providing a mineral residue, which includes a core and a shell around the core. In certain examples, the core comprises calcium (Ca), magnesium (Mg), or a combination thereof. The Ca and Mg is not present as elemental Ca or Mg but rather as a compound of Ca or of Mg, such as but not limited to Ca(OH).sub.2 or Mg(OH).sub.2. In certain examples, the shell comprises an oxide, a hydroxide, a carbonate, a silicate, a sulfite, a sulfate, a chloride, a nitrate, or nitrite, of calcium (Ca) or of magnesium (Mg), or a combination thereof. The process includes (a) fractionating the mineral residue; (b) contacting the mineral residue with an acid and fractionating the mineral residue; or (c) contacting the mineral residue with a base and fractionating the mineral residue. As a result, the mineral residue's core is exposed. In some examples, the shell is passivating and inhibits the Ca or Mg, or both, in the core from reacting with carbon dioxide (CO.sub.2). By exposing the core as described herein, a mineral residue's reactivity with carbon dioxide is increased.

A method of forming a product for separating gases includes forming a three-dimensional ceramic support, heating the three-dimensional ceramic support at a temperature for an effective duration of time to result in the conductive ceramic material having a plurality of intra-material pores, and incorporating a sorbent additive into the intra-material pores of the conductive ceramic material. Moreover, the three-dimensional ceramic support includes an electrically conductive ceramic material configured for joule heating.

A method for regenerating an amine-containing sorbent material useful in CO.sub.2 capture, the method comprising exposing an amine-containing sorbent-CO.sub.2 complex to microwave radiation to result in release of CO.sub.2 and regenerated amine-containing sorbent that is uncomplexed with CO.sub.2, wherein the amine-containing sorbent-CO.sub.2 complex contains either: (i) a carbamate bond; or (ii) an ion pair bond of the formula

##STR00001##

wherein R.sup.a, R.sup.b, and R.sup.c are selected from H and hydrocarbon groups containing at least one carbon atom, wherein at least one of R.sup.a, R.sup.b, and R.sup.c is H; X.sup.m? is a carbonate or bicarbonate anion, with m being 1 for bicarbonate and 2 for carbonate; and n is an integer of 1 or 2, provided that n?m=2. The method may also include re-using the regenerated amine-containing sorbent to capture carbon dioxide.

Described herein are compositions and methods for the storage and release of hydrogen gas using covalent organic frameworks (COFs). Advantageously, the compositions and methods described herein may be used for the facile and rapid release of hydrogen gas at near ambient temperatures. The described COFs allow for photoactivation, where the release of gas is initiated or the rate of release is increased with the COF is exposed to electromagnetic radiation, for example, UV light.

The present disclosure relates to a fluid treatment apparatus. The fluid treatment apparatus includes a first system for removing one or more target compounds from a fluid, said first system comprising adsorbent particles; a second system for regenerating said adsorbent particles; a first connector between said first system and said second system, said first connector configured to transfer adsorbent particles from said first system to said second system; and a second connector between said first system and said second system, said second connector configured to release of adsorbent particles from said second system, wherein said first system and said second system are decoupled. The present disclosure further relates to a system comprising one or more fluid treatment apparatus described herein. Also described herein are methods for treating fluid and a system comprising the methods for treating fluid described herein.

A method for regeneration of a carbon dioxide absorbent includes steps of a) bringing a used carbon dioxide absorbent in contact with a carbon-containing dielectric material to form a dielectric energy-susceptible combination, and b) subjecting the dielectric energy-susceptible combination to a dielectric heating to remove carbon dioxide from the used carbon dioxide absorbent for the regeneration.

A process for purification of a carbon dioxide feedstock that includes carbon dioxide and gaseous and liquid C.sub.1+ hydrocarbons. Specifically, a carbon dioxide feedstream is passed through one or more separation unit, each separation unit removing one or more C.sub.1+ hydrocarbon from the carbon dioxide feedstream to provide a richer carbon dioxide gas stream. The one or more separation unit employs an adsorption media and has an adsorption step and a media regeneration step.

A method is described to regenerate an oxygen trap, comprising at least the following steps: circulating a current in the trap material (2) to reduce this material; measuring the value I.sub.m of the current and estimating its derivative dI.sub.m/dt in relation to time; estimating the length () of material reduced by the current as a function of the value of the current and its derivative; stopping circulation of the current when the length of reduced material is at least equal to a threshold value (.sub.s).