Energy and exergy performances of low-density polyethylene plastic particles assisted by microwave heating.

Plastic waste can exist naturally for hundreds of thousands of years and harm humans, animals, and the environment. In this study, the energy and exergy performances (absorbed energy, energy efficiency, absorbed exergy, and exergy efficiency) of LDPE (low-density polyethylene) plastic particles assisted by microwave heating based on the experimental data as affected by microwave power, feeding load, and chamber volume were evaluated and analyzed. The results showed that as the microwave power raised from 500 to 900 W, the feeding load changed from 10 to 30 g, and the chamber volume decreased from 200 to 100 ml, (a) the absorbed energy at the heating time of 60 min increased from 19.73 kJ, 5.84 kJ, and 22.71 kJ to 37.69 kJ; (b) the energy efficiency for the whole heating process increased from 1.10%, 0.32%, and 1.26% to 2.09%; (c) the absorbed exergy at the heating time of 60 min increased from 0.308, 0.091, and 0.091 to 0.724 kJ; and (d) the exergy efficiency for the whole heating process increased from 0.017, 0.005, and 0.023 to 0.040%, respectively.

Experimental microwave-assisted air gasification of biomass in fluidized bed reactor.

Microwave-assisted heating is an effective heating method for thermochemical conversion of biomass. In this study, experimental syngas production from microwave-assisted air gasification of biomass in a fluidized bed reactor at different gasification temperatures, equivalence ratios and silicon carbide loads, was studied and reported. The results showed that the highest syngas yield (78.2 wt%), higher heating value (6.3 MJ/Nm3) and cold gas efficiency (81.8 %) were obtained at gasification temperature of 900 °C, equivalence ratio of 0.35 and silicon carbide load of 30 g, and the gasification temperature had significant influence on the syngas production. Microwave-assisted heating showed positive effect on tar reduction, i.e., the tar content at 900 °C (2.1 wt%) in this study was even lower than the tar content (3.2 wt%) from catalytic electrical air gasification of rice husk at 950 °C. Generally, the introduction of microwave-assisted heating showed positive effect on biomass gasification.

2,2'-Biphenol-based Ultrathin Microporous Nanofilms for Highly Efficient Molecular Sieving Separation.

Organic solvent nanofiltration (OSN) is an emerging membrane separation technology, which urgently requires robust, easily processed, OSN membranes possessing high permeance and small solutes-selectivity to facilitate enhanced industrial uptake. Herein, we describe the use of two 2,2'-biphenol (BIPOL) derivatives to fabricate hyper-crosslinked, microporous polymer nanofilms through IP. Ultra-thin, defect-free polyesteramide/polyester nanofilms (≈5 nm) could be obtained readily due to the relatively large molecular size and ionized nature of the BIPOL monomers retarding the rate of the IP. The enhanced microporosity arises from the hyper-crosslinked network structure and monomer rigidity. Specifically, the amino-BIPOL/PAN membrane exhibits extraordinary permselectivity performances with molecular weight cut-off as low as 233 Da and MeOH permeance of ≈13 LMH/bar. Precise separation of small dye mixtures with similar M.W. based on both their charge and molecular size are achieved.