High-density polyethylene (HDPE) was pyrolyzed over HZSM-5 catalyst using a specially developed laboratory fluidized-bed reactor operating isothermally at ambient pressure. The influence of reaction conditions including temperature, ratios HDPE to feed, and flow rates fluidizing gas examined. sodium form siliceous ZSM-5, silicalite, containing very few or no catalytically active sites, gave low conversions polymer volatile hydrocarbons compared with (Si/Al = 17.5) under the same conditions....

The quenched solid density functional theory (QSDFT) is employed to study methane adsorption on coal at geological conditions. main focus made deformation in the course of that may result either expansion/swelling or contraction, depending upon pressure, temperature, and pore size. Two qualitatively different types behavior were found width. Type I shows a monotonic expansion whole pressure range. This characteristic for smallest pores <1.3σff (0.5 nm) cannot accommodate more than one layer...

We present a local superbasin kinetic Monte Carlo (LSKMC) method that efficiently treats multiple-time-scale problems in (KMC). The is designed to solve the small-barrier problem created by groups of recurrent free-energy minima connected low barriers and separated from full phase space system high barriers. propose an algorithm detect, on fly, consolidate them into “superbasins,” which we treat with rate equations and/or absorbing Markov chains. discuss various issues involved implementing...

[1] Adsorption-induced deformation of coal during carbon dioxide sequestration in seams at elevated pressures and temperatures is studied with the quenched solid density functional theory (QSDFT) model. Two types behaviors pores different sizes can be identified from dependence solvation pressure on CO2 pressure. The smallest micropores (<0.5 nm, 360 K) monotonically expand as increases. larger (>0.5 nm) tend to contract low (1–10 MPa); however, this low-pressure contraction followed by...

The first-order mean spherical approximation (FMSA) theory proposed by Tang et al. [Fluid Phase Equilib., 134, 21(1997)] is applied for studying several typical Yukawa fluids, including attractive, repulsive, and multi-Yukawa cases. FMSA study particularly advantageous in providing thermodynamics structure information a simple, analytical, consistent manner. Comparisons with the latest reported computer simulation data compressibility factor, internal energy, radial distribution function...

The lithium-carbon binary system possesses a broad range of chemical compounds, which exhibit fascinating bonding characteristics, give rise to diverse and technologically important properties. While lithium carbides with various compositions have been studied or suggested previously, the crystal structures these compounds are far from well understood. In this work, we present first comprehensive survey all ground state (GS) over thermodynamic conditions, using ab initio density functional...

Catalytic pyrolysis of polymers over catalysts has the potential to recover valuable hydrocarbons from waste materials. Polyolefins were pyrolyzed using a specially developed laboratory fluidized bed reactor operating isothermally at ambient pressure. The systematic experiments carried out with several show that under appropriate reaction conditions, may be selected reduce required temperature, improve yield volatile products, and provide selectivity in product distributions. A kinetic model...

A recently proposed analytical equation of state (EOS) for the hard-core two-Yukawa fluids is tested against results Monte Carlo (MC) simulation in six cases. One range parameter potential taken as 1.8 or 2.8647, and another 2.0, 4.0, 8.0, 13.5485. Attractive repulsive dominant cases outside core are all considered. The conditions selected ensure that, interaction between two particles attractive at enough long distance. Some can give similar that charged colloid particles. fluid with...