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• Three shrinking cylinder models are proposed. • The new models are suitable for materials with a high aspect ratio. • Some suggestions to the kinetic analysis in uncatalyzed reactions are provided. The shrinking unreacted core model has been one of the most widely used models for the uncatalyzed reaction kinetics between the liquid/gas and the solid phases. However, the classical shrinking unreacted core model (CSUC model) is only applicable to spherical particles. Currently, the CSUC model has been used in many studies regardless of its applicable conditions. For example, Wang et al. (2016) investigated the decomposition kinetics of a rod-like residue and deduced the rate-controlling step using the CSUC model. The purpose of this comment is to propose a modified shrinking unreacted core model (shrinking cylinder model) suitable for materials with a high aspect ratio. The authors hope that this work will be helpful for kinetic analysis of rod-shaped and fiber-shaped materials in the uncatalyzed liquid/gas-solid reactions. [ABSTRACT FROM AUTHOR]

Abstract: The effect of sorbed nonylphenol (NP) at low levels on phenanthrene sorption onto the mineral surfaces (organic-removed sediment, kaolinite) and a natural sediment with low organic content was investigated in this study. NP could be sorbed on the sediment and the minerals, and part of sorbed NP interacted with the solid surface stably. At very low concentrations, sorbed NP was observed to inhibit the sorption of phenanthrene on the hydrophilic mineral surfaces (organic-removed sediment and kaolinite) based on the change of phenanthrene apparent solid–liquid distribution coefficients. When the amount of sorbed NP increased to higher levels, enhancement of phenanthrene sorption occurred. Similar result was also obtained in isotherm experiments. On the mineral sorbents contacting with 1.0mg/L NP solution previously, the K d values were lower compared with those on the sorbents without sorbed NP. On the sorbents with higher levels of sorbed NP (contacting with 10mg/L NP solution previously), the K d values increased, while the isotherm tended to be more nonlinear. Concentrations of sorbed NP determined its orientation on the surface, which could presumably affect the water film above the sorbents, or contribute more adsorption sites for phenanthrene. [Copyright &y& Elsevier]