New carbon capture materials: Novel approaches to post-combustion CO2 capture

The most commercially viable capture method in carbon capture and storage (CCS) has been attributed to post-combustion carbon capture using chemical solvents. Although the conventional chemical solvents such as MEA solutions have high selectivity and capture capacity, they are highly corrosive and required high regeneration energy. In addition, volatilisation of MEA at elevated temperature and its release to the atmosphere can lead to major human and environment concerns. In this study two alternative carbon capture materials have been investigated

Fundamental investigation of compound jet pinch-off and double-emulsion formation in glass capillary microfluidic devices

Fundamental investigation of compound jet pinch-off and double-emulsion formation in glass capillary microfluidic device

Structured biodegradable polymeric microparticles for drug delivery produced using flow focusing glass microfluidic devices

Biodegradable poly(DL-lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA) microparticles with tunable size, shape, internal structure and surface morphology were produced by counter-current flow focusing in axisymmetric (3D) glass capillary devices. The dispersed phase was composed of 0.5-2 wt% polymer solution in a volatile 2 organic solvent (ethyl acetate or dichloromethane) and the continuous phase was 5 wt% aqueous poly(vinyl alcohol) solution. The droplets with a coefficient of variation in dripping regime below 2.5 % were evaporated to form polymeric particles with uniform sizes ranging between 4-30 μm. The particle microstructure and surface roughness were modified by adding nanofiller (montmorillonite nanoclay) or porogen (2-methylpentane) in the dispersed phase to form less porous polymer matrix or porous particles with golf-ball-like dimpled surface, respectively. The presence of 2-4 wt% nanoclay in the host polymer significantly reduced the release rate of paracetamol and prevented the early burst release, as a result of reduced polymer porosity and tortuous path for the diffusing drug molecules. Numerical modelling results using the volume of fluid-continuum surface force model agreed well with experimental behaviour and revealed trapping of nanoclay particles in the dispersed phase upstream of the orifice at low dispersed phase flow rates and for 4 wt% nanoclay content, due to vortex formation. Janus PLA/PCL (polycaprolactone) particles were produced by solvent evaporation-induced phase separation within organic phase droplets containing 3 % (v/v) PLA/PCL (30/70 or 70/30) mixture in dichloromethane. A strong preferential adsorption of Rhodamine 6G dye onto PLA was utilized to identify PLA portions of the Janus particles by Confocal Laser Scanning Microscopy (CLSM). Uniform hemispherical PCL particles were produced by dissolution of PLA domes with acetone

Semipermeable elastic microcapsules for gas capture and sensing

Monodispersed microcapsules for gas capture and sensing were developed consisting of elastic semipermeable polymer shells of tuneable size and thickness and pH-sensitive, gas selective liquid cores. The microcapsules were produced using glass capillary microfluidics and continuous on-the-fly photopolymerisation. The inner fluid was 5-30 wt% K2CO3 solution with m-cresol purple, the middle fluid was a UV-curable liquid silicon rubber containing 0-2 wt% Dow Corning® 749 fluid, and the outer fluid was aqueous solution containing 60-70 wt% glycerol and 0.5-2 wt% stabiliser (polyvinyl alcohol, Tween 20 or Pluronic® F-127). An analytical model was developed and validated for prediction of the morphology of the capsules under osmotic stress based on the shell properties and the osmolarity of the storage and core solutions. The minimum energy density and UV light irradiance needed to achieve complete shell polymerisation were 2 J∙cm-2 and 13.8 mW·cm-2, respectively. After UV exposure, the curing time for capsules containing 0.5 wt% Dow Corning® 749 fluid in the middle phase was 30-40 min. The CO2 capture capacity of 30 wt% K2CO3 capsules was 1.6-2 mmol/g depending on the capsule size and shell thickness. A cavitation bubble was observed in the core when the internal water was abruptly removed by capillary suction, whereas a gradual evaporation of internal water led to buckling of the shell. The shell was characterised using TGA, DSC, and FTIR. The shell degradation temperature was 450-460°C

Parametric investigation of CO2-MIPs production using suspension polymerisation method

Parametric investigation of CO2-MIPs production using suspension polymerisation metho

Microparticles production for drug delivery using glass microfluidic devices

Microparticles production for drug delivery using glass microfluidic device

Hydrogen Transfer Hydrogenolysis of Organosolv Chinese Fir Lignin to Monophenols over NiZnAlO_<i>x</i> Catalyst

Lignin is the only naturally renewable aromatized polymer consisting of several phenyl propane structures linked by C–O and C–C bonds, so lignin can be depolymerized into value-added chemicals or liquid fuels. In this study, M5Zn5AlOx (M = Co, Ni and Cu) catalysts were obtained by the co-precipitation method and then were used in organosolv lignin depolymerization. Among these catalysts, the Ni5Zn5AlOx catalyst possessed the largest surface area and abundant surface oxygen vacancies as well as strong acidic sites on the surface, giving the highest yield of monophenols (about 14.49 wt %). The effect of Ni/Zn ratios on the lignin depolymerization was also investigated, and it was found that the surface area and the proportion of surface oxygen vacancies and strong acidic sites of the NiZnAlOx catalysts increased and then decreased with the Ni/Zn ratios increasing. Similarly, the yield of monomeric compounds increased and then decreased with the Ni/Zn ratios increasing. The highest yield of monophenols was 17.18 wt % obtained over the Ni3Zn7AlOx catalyst, a remarkable monomer yield from organosolv lignin. The two-dimensional 1H-13C heteronuclear single-quantum coherence nuclear magnetic resonance spectroscopy of bio-oil revealed that the linkage bonds in lignin could be effectively broken over the Ni3Zn7AlOx catalyst. This study provided an effective route to obtain high-value chemicals from organosolv lignin under nickel-based catalysts

Structured Biodegradable Polymeric Microparticles for Drug Delivery Produced Using Flow Focusing Glass Microfluidic Devices

Biodegradable poly­(dl-lactic acid) (PLA) and poly­(lactic-<i>co</i>-glycolic acid) (PLGA) microparticles with tunable size, shape, internal structure and surface morphology were produced by counter-current flow focusing in axisymmetric (3D) glass capillary devices. The dispersed phase was composed of 0.5–2 wt % polymer solution in a volatile organic solvent (ethyl acetate or dichloromethane) and the continuous phase was 5 wt % aqueous poly­(vinyl alcohol) solution. The droplets with a coefficient of variation in dripping regime below 2.5% were evaporated to form polymeric particles with uniform sizes ranging between 4 and 30 μm. The particle microstructure and surface roughness were modified by adding nanofiller (montmorillonite nanoclay) or porogen (2-methylpentane) in the dispersed phase to form less porous polymer matrix or porous particles with golf-ball-like dimpled surface, respectively. The presence of 2–4 wt % nanoclay in the host polymer significantly reduced the release rate of paracetamol and prevented the early burst release, as a result of reduced polymer porosity and tortuous path for the diffusing drug molecules. Numerical modeling results using the volume of fluid-continuum surface force model agreed well with experimental behavior and revealed trapping of nanoclay particles in the dispersed phase upstream of the orifice at low dispersed phase flow rates and for 4 wt % nanoclay content, due to vortex formation. Janus PLA/PCL (polycaprolactone) particles were produced by solvent evaporation-induced phase separation within organic phase droplets containing 3% (v/v) PLA/PCL (30/70 or 70/30) mixture in dichloromethane. A strong preferential adsorption of Rhodamine 6G dye onto PLA was utilized to identify PLA portions of the Janus particles by confocal laser scanning microscopy (CLSM). Uniform hemispherical PCL particles were produced by dissolution of PLA domes with acetone