Abstract: The present disclosure provides fluorinated crown ethers. The fluorinated crown ethers have one or more pendant fluorinated groups (e.g., thioether groups with a terminal fluorinated group). The fluorinated crown ethers have desirable solubility in supercritical carbon dioxide. Also provided are methods and systems for removal of lithium (e.g., lithium ions) from aqueous samples using the fluorinated crown ethers coupled with lipophilic cation exchangers.

Abstract: The present disclosure provides fluorinated crown ethers. The fluorinated crown ethers have one or more pendant fluorinated groups (e.g., thioether groups with a terminal fluorinated group). The fluorinated crown ethers have desirable solubility in supercritical carbon dioxide. Also provided are methods and systems for removal of lithium (e.g., lithium ions) from aqueous samples using the fluorinated crown ethers coupled with lipophilic cation exchangers.

Abstract: A process for pretreatment of a biomass material, comprising subjecting a biomass material to a biphasic mixture of water and supercritical CO2 at a temperature in the range of 150° C. to 250° C. under high pressure for a time of from 10 seconds to 100 minutes. In particular embodiments, the process is performed as a two-stage temperature process wherein an initial short high-temperature stage is conducted at a temperature of at least 200° C. for up to 20 minutes and a subsequent longer low-temperature stage is conducted at a temperature of at least 140° C. and up to 190° C. for 10-120 minutes.

Abstract: A process for pretreatment of a biomass material, comprising subjecting a biomass material to a biphasic mixture of water and supercritical CO2 at a temperature in the range of 150° C. to 250° C. under high pressure for a time of from 10 seconds to 100 minutes. In particular embodiments, the process is performed as a two-stage temperature process wherein an initial short high-temperature stage is conducted at a temperature of at least 200° C. for up to 20 minutes and a subsequent longer low-temperature stage is conducted at a temperature of at least 140° C. and up to 190° C. for 10-120 minutes.

Abstract: Various rock spallation devices and methods reduce the cost of deep hole excavation. A spallation head has rotating, circumferentially spaced jets. The jets may be combustion flame jets or very hot water. In a combustion embodiment, air and water are delivered to the spallation apparatus downhole in a mixture, and are separated. In a low density embodiment, the borehole is essentially empty. In a high density embodiment, more water is included in the mixture of air and water, and the borehole is filled with fluid. Instead of combustion, the kinetic energy of flowing water at the spallation device can be used to power a turbogenerator that generates electric energy to heat the water and spall the rock. The jets may also be aimed and configured to fuse the excavation material, if spallation is not feasible. New lengths of feed and return pipe can be added while spallation continues uninterrupted, either due to well head alternating equipment, or a downhole relative motion device.