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The solubilities of adipic acid in cyclohexanol + cyclohexanone mixtures from 303.0 to 353.0 K and in cyclohexanone + cyclohexane mixtures from 303.0 to 378.5 K were determined using a titration and an in situ ATR-FTIR method. The averaged relative deviation between two methods at given temperatures was less than 2%. The solubility of adipic acid in cyclohexanone + cyclohexane mixtures increases with increasing mass fraction of cyclohexanone in the mixtures at given temperatures. However, the solubility of adipic acid in cyclohexanol + cyclohexanone mixtures reaches the maximum at cyclohexanone mass fraction of 0.4. The experimental data were well correlated by Apelblat equation and λh equation. The thermodynamics functions of the dissolution process were calculated by van't Hoff equation.

A novel sulfonated bamboo-derived carbon (SBC) was prepared through a one-pot simultaneous carbonization and sulfonation method using ptoluenesulfonic acid as the sulfonating agent. This method was used in place of the two-step method of high temperature carbonization followed by sulfonation, in order to reduce energy consumption and avoid the use of substantial amounts of strong liquid acid. The as-prepared catalyst bearing SO3H, COOH, and phenolic OH groups demonstrated efficient catalytic activity in the dehydration of fructose to 5-hydroxymethylfurfural (HMF), achieving 92.1% HMF yield in a mixture of tetrahydrofuran (THF) and dimethylsulfoxiden (DMSO) (volume ratio of THF/DMSO 3/7). The mixture had a fructose concentration of 0.08 g·mL -1 with a catalyst amount of 10% weight of fructose at 140 °C in 60 min. No distinct activity drop was observed after the initial deactivation during 5 recycling runs, confirming a good stability of the prepared catalyst. Moreover, kinetic data showed that SBC promoted fructose dehydration to HMF may follow pseudo-first order kinetics with the activation energy of 43.6 kJ·mol -1 under investigated conditions. The convenient catalyst preparation method and excellent catalytic performance of the catalyst provide an easy-handling and ecofriendly strategy for crude biomass utilization in catalyst production.

The polymerization of tetrahydrofuran (THF) was carried out in CH2Cl2 by using phosphotungstic heteropolyacid as initiator and epichlorohydrin as promoter. This cationic ring‐opening polymerization process was monitored by in situ mid‐infrared spectroscopy system (ReactIR) to further study the thermodynamics and kinetics of THF polymerization. It was observed that the sharp infrared peak of COC stretching vibrations will shift from about 1068 to 1109 cm−1 in THF ring‐opening step. The changes in absorbance intensity of the two characteristic peaks were used for determining instantaneous concentration of linear polymer and ring monomer. The experimental results demonstrated that the kinetics of THF polymerization proved to be typically first‐order. Thermodynamic parameters were determined from the temperature dependence of the monomer equilibrium concentration [M]e over the range from −5 to 25°C. The values of kapp were obtained via the plots of ln{([M]0−[M]e)/([M]t−[M]e)} vs reaction time, for polymerization under specific conditions. The apparent activation energy (Ea) and frequency (A) were determined from the Arrhenius plot of kapp vs. T−1. Besides, the in situ kinetic investigation revealed that more chain‐transfer occurred at higher temperatures, leading to a reduction in propagation species concentration and a deviation from first‐order propagation at the later stage of polymerization. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40503.