Arabian Heavy crude oil was fractionated into distillate and vacuum residue fractions. The vacuum residue fraction was treated with supercritical water (SCW) at 450 °C in a batch reactor for 15 to 90 minutes. The main products were gas, coke, and upgraded vacuum residue; the upgraded residue consisted of gasoline, diesel, and vacuum gas oil range components. The molecular composition of gas and upgraded vacuum residue was analyzed using gas chromatography (GC, GC×GC). SCW treatment converted higher carbon number aliphatics (≥ C21) and long chain (≥ C5) alkyl aromatic compounds into C1-C20 aliphatics, C1-C10 alkylaromatics and multi-ringed species. The concentrations of gasoline and diesel range compounds were greater in the upgraded product, compared to the feed. A first-order, five lump reaction network was developed to fit the yields of gas, coke, diesel and gasoline range components obtained from SCW upgrading of vacuum residue. Distillation of crude oil followed by SCW treatment of the heavy fraction approximately doubled the yield of chemicals, gasoline, and diesel, while forming significantly less coke than conventional upgrading methods. ** Many of the results in this manuscript were presented by S. Gudiyella at the 2016 AIChE Annual Meeting, identified as the Best Presentation in the session "Reaction Engineering of Biomass and Hydrocarbons in Supercritical Water" by the Session Chair K. Choi.

Type II porous liquids, comprising intrinsically porous molecules dissolved in a liquid solvent, potentially combine the adsorption properties of porous adsorbents with the handling advantages of liquids. Previously, discovery of appropriate solvents to make porous liquids had been limited to direct experimental tests. We demonstrate an efficient screening approach for this task that uses COSMO-RS calculations, predictions of solvent pK a values from a machine-learning model, and several other features and apply this approach to select solvents from a library of more than 11,000 compounds. This method is shown to give qualitative agreement with experimental observations for two molecular cages, CC13 and TG-TFB-CHEDA, identifying solvents with higher solubility for these molecules than had previously been known. Ultimately, the algorithm streamlines the downselection of suitable solvents for porous organic cages to enable more rapid discovery of Type II porous liquids.

The synthesis and functionalization of porous organic cages (POCs) for separation have attracted growing interest over the past decade. However, the potential of solid-phase POCs for practical, large-scale separations will require incorporation into appropriate gas–solid or liquid–solid contactors. Contactors with more effective mass transfer properties and lower pressure drops than pelletized systems are preferred. Here, we prepared and characterized fiber sorbents with POCs throughout a cellulose acetate (CA) polymer matrix, which were then deployed in model separations. The POC CC3 was shown to be stable after exposure to spinning solvents, as confirmed by NMR, powder X-ray diffraction, and gas sorption experiments. CC3-CA fibers were spun using the dry-jet wet-quench spinning method. Spun fibers retained the adsorptive properties of CC3 powders, as confirmed by CO2 and N2 physisorption and TGA, reaching upward of 60 wt % adsorbent loading, whereas the pelletized CC3 counterparts suffered significant losses in textural properties. The separation capabilities of the CC3-CA fibers are tested with both simulated postcombustion flue gas and with Xe/Kr mixtures. Fixed bed breakthrough experiments performed on fibers samples show that CC3 embedded in polymeric fibers can effectively perform these proof-of-concept gas separations. The development of fiber sorbents embedded with POCs provides an alternative to traditional pelletization for the incorporation of these materials into adsorptive separation systems.

Solvent-based absorption systems are frequently used for industrial-scale CO2 capture from point sources. Physical and chemical solvents are well understood; however, there are drawbacks such as low gas capacity, high regeneration energy, and large operating units. Porous liquids (liquids with intrinsic microporosity) present an opportunity to improve the effectiveness of solvent-based separation processes, especially physisorption-based systems. Type II porous liquids are developed by dissolving a discrete, microporous material in a sterically hindered solvent that cannot penetrate the pores of the porous material. These liquids exhibit dual-mode sorption (i.e., Henry + Langmuir) and show excellent potential for gas separations. In this work, a first-order high-pressure CO2/CH4 separation process is modeled using a porous liquid comprised of a discrete porous material dissolved in a sterically hindered solvent. Gas–liquid phase equilibria of the porous liquids are modeled using gas-cage equilibrium data. A McCabe–Thiele approach is employed to estimate the amount of solvent and size of the absorption tower needed compared to an industrial solvent, revealing that porous liquids can decrease the capital needed to adequately separate a gaseous mixture. The energy requirements for a variety of regeneration scenarios are calculated, highlighting that porous liquids can lower the energy burden necessary for gas separation processes. The porous liquid shows the potential to significantly reduce the solvent consumption and size of operating units for this gas separation, with the potential to lower the overall cost and energy required to capture CO2.