• Energy Research

Lithium was enriched up to 10 000 ppm from seawater by a continuous electrical pumping membrane process and collected as battery-grade product by simple precipitation.

Power to formic acidviaCO2hydrogenation or electrochemical CO2reduction has great potential to enable a complete cycle with formic acid to power for the storage and utilization of low-carbon electricity at a scale of multi-gigatonnes per year.

The synthesis of metal–organic frameworks (MOFs) directly starting from biomass, making the most of renewable feedstocks and allowing for coupled or continuous processing, is intriguing. The interference of water (vapor) greatly hinders the wide utilization of MOFs in, e.g., recovering ethane from humid shale gas, which is a critical process for purifying natural gas in practical scenarios. Here, we propose a concept of direct ligand and MOF synthesis in a continuous routine, i.e., a linear synthesis of a bioderived ligand (furan-2,5-dicarboxylic acid), starting from a biomass source (fructose), followed by the in situ synthesis of a series of different MOFs. This strategy is also exempt from the tedious and energy-intensive processes of filtering, purifying, or drying intermediate products. The obtained renewable MOFs, particularly MIL-160(Al), reveal superior ethane capture abilities from shale gas mixtures under ambient conditions compared to most of the MOF materials reported to date. MIL-160(Al) also demonstrates a remarkable cycling nature and facile sorption regenerability to selectively capture ethane even under high-humidity conditions, as verified by static gas sorption measurement, experimental breakthrough tests, and in-depth theoretical studies, further conferring it with great potential for industrial applications. ; Y.-M.G., S.Q., T.-J.S., and S.-D.W. are grateful to the National Natural Science Foundation of China for funding (Grant No. 21776266) and Yangquan Coal Industry (Group) Co. LTD., China, for the financial support through the R&D project of “Upgrade of 300 Nm3 h−1 Low Concentration Coal Bed Methane by A Rapid Cycle Pressure Swing Adsorption Process”. X.-W.L. and Z.L. appreciate the support from King Abdullah University of Science and Technology (KAUST) for the competitive research grant URF/1/3769-01. The authors acknowledge Dr. Chang Wang and Dr. Pei-Fang Yan at the Division of Energy Research Resources, DICP, for their support in structure measurement and water adsorption ...

AbstractWe present adsorption and desorption isotherms of methane, ethane, propane, n-butane and iso-butane as well as carbon dioxide for two shales and isolated kerogens determined by a gravimetric method. The sorption measurements of two shales were performed at three different temperatures, 308.15, 323.15, and 338.15 K. For the isolated kerogens, the measurements were conducted at 338.15 K. Methane and ethane sorption isotherms were measured to 35 bar. Carbon dioxide sorption isotherms were studied to 30 bar. Due to the low vapor pressure at room temperature, the sorption isotherms of propane, n-butane and iso-butane were measured to 8, 2, and 2 bar, respectively. The adsorptions of propane, n-butane, and iso-butane were much higher than methane at the highest pressures where the measurements were conducted. The adsorption of n-butane was 10 times higher than methane by mole at 2 bar, followed by iso-butane and propane. Our data show significant adsorption hysteresis in ethane, propane, n-butane and iso-butane. The most pronounced hysteresis was found in n-butane and iso-butane. Significant hysteresis is attributed to the reversible structural changes of kerogens. Dissolution of adsorbates into organic matter may also affect the hysteresis. This is the first report of propane and butane sorption isotherms in shales.

The osmotic heat engine (OHE) is a promising technology for converting low grade heat to electricity. Most of the existing studies have focused on thermolytic salt systems. Herein, for the first time, we proposed to use thermally responsive ionic liquids (TRIL) that have either an upper critical solution temperature (UCST) or lower critical solution temperature (LCST) type of phase behavior as novel thermolytic osmotic agents. Closed-loop TRIL-OHEs were designed based on these unique phase behaviors to convert low grade heat to work or electricity. Experimental studies using two UCST-type TRILs, protonated betaine bis(trifluoromethyl sulfonyl)imide ([Hbet][Tf2N]) and choline bis(trifluoromethylsulfonyl)imide ([choline][Tf2N]) showed that (1) the specific energy of the TRIL-OHE system could reach as high as 4.0 times that of the seawater and river water system, (2) the power density measured from a commercial FO membrane reached up to 2.3 W/m2, and (3) the overall energy efficiency reached up to 2.6% or 18% of the Carnot efficiency at no heat recovery and up to 10.5% or 71% of the Carnet efficiency at 70% heat recovery. All of these results clearly demonstrated the great potential of using TRILs as novel osmotic agents to design high efficient OHEs for recovery of low grade thermal energy to work or electricity.

Pincers do the trick: The conversion of ethanol to ethyl acetate and hydrogen was achieved using a pincer-Ru catalyst in a Pd-Ag membrane reactor. Near quantitative conversions and yields could be achieved without the need for acid or base promoters or hydrogen acceptors (see scheme).

Abstract The feasible capture and separation of CO2 and N2 from CH4 is an important task for natural gas upgrading and the control of greenhouse gas emissions. Here, we studied the microporous covalent imine networks (CIN) material prepared through Schiff base condensation and exhibited superior chemical robustness under both acidic and basic conditions and high thermal stability. The material possesses a relatively uniform nanoparticle size of approximately 70–100 nm. This network featured permanent porosity with a high surface area (722 m2/g) and micropores. A single-component gas adsorption study showed enhanced CO2 and CH4 uptakes of 3.32 mmol/g and 1.14 mmol/g, respectively, at 273 K and 1 bar, coupled with high separation selectivities for CO2/CH4, CH4/N2, and CO2/N2 of 23, 11.8 and 211, respectively. The enriched Lewis basicity in the porous skeletons favours the interaction of quadrupolar CO2 and polarizable CH4, resulting in enhanced CH4 and CO2 uptake and high CH4/N2, CO2/CH4 and CO2/N2 selectivities. Breakthrough experiments showed high CO2/CH4, CH4/N2 and CO2/N2 selectivities of 7.29, 40 and 125, respectively, at 298 K and 1 bar. High heats of adsorption for CH4 and CO2 (QstCH4; 32.61 kJ mol−1 and QstCO2; 42.42 kJ mol−1) provide the ultimate validation for the high selectivity. To the best of our knowledge, such a versatile adsorbent material that displays both enhanced uptake and selectivity for a variety of binary gas mixtures, including CO2/CH4, CO2/N2 and CH4/N2, has not been extensively explored.

AbstractThis study proposes a strategy for optimal design of hollow fiber membrane networks for post combustion carbon capture from power plant multicomponent flue gas. A mathematical model describing multicomponent gas permeation through a separation membrane was customized into the flowsheet modeling package ASPEN PLUS. An N-stage membrane network superstructure was defined considering all possible flowsheeting configurations. An optimization formulation was then developed and solved using an objective function that minimizes the costs associated with operating and capital expenses. For a case study of flue gas feed flow rate of 298 m3/s with 13% CO2 and under defined economic parameters, the optimization resulted in the synthesis of a membrane network structure consisting of two stages in series. This optimal design was found while also considering feed and permeate pressures as well as recycle ratios between stages. The cost of carbon capture for this optimal membrane network is estimated to be $28 per tonne of CO2 captured, considering a membrane permeance of 1000 GPU and membrane selectivity of 50. Following this approach, a reduction in capture cost to less than $20 per tonne CO2 captured is possible if membranes with permeance of 2000 GPU and selectivity higher than 70 materialize.