Advanced Materials Research Vols. 550-553

Abstract: The decolorization behaviors of a triphenodioxazine reactive dye (C.I. Reactive Blue 198) in the activated oxygen bleach system containing sodium perborate (PB) and tetra-acetylethylenediamine (TAED) were investigated. The decolorization kinetics of the dye was found to follow the first-order kinetic model and the rate constant of decolorization increased significantly with increasing temperature. The activation energy for decolorizing reaction was 50.41 kJ/mol. The highest rate constant appeared at pH 8. The triphenodioxazine reactive dye showed poor stability to activated oxygen washing.

Abstract: Atmospheric vapor-liquid equilibrium data of methyl ethyl ketone (MEK) - methyl isobutyl ketone (MIBK) were measured using an improved Rose still and were used to recover the parameters of NRTL and UNIQUAC models. The results show that the simulated results agree well with the experimental data. The mean temperature variation is 0.14 °C and the mean mole fraction variation is 0.0023 using UNIQUAC model while the mean temperature variation is 0.17 °C and the mean mole fraction variation is 0.0025 using NRTL model. Both models can be used to calculate the atmospheric vapor-liquid equilibrium data of MEK - MIBK.

Abstract: The distribution of boron between solid silicon and melt Si-Al alloy (K_B) and the interaction coefficients between aluminum and boron in solid silicon were investigated by establishing the equilibrium between Si–B alloy and aluminum at 1623 K ~ 1723 K for 4 h and then quenching them to obtain the content of boron and aluminum in silicon and Si-Al melt. The results shown that the distribution coefficients of boron KB are 0.139~0.325 (1623K), 0.332~0.587 (1673K), 0.684~0.956 (1723K), and the interaction coefficients are 32.8±2.34 (1623K), 16.3±1.17 (1673K) and 8.2±0.6 (1723K).

Abstract: The paper analyzed the adsorption conditions of uranium on carboxylic acid fiber. The isotherms were drawn, and Langmuir and Freundlich equations were deduced. The adsorption kinetics of UO₂ ²⁺on carboxylic fiber was researched. The rate constant of adsorption was obtained and the apparent activation energy was determined. This research provides a theoretical basis for new adsorbents of uranium in nuclear wastes.

Abstract: In order to purify the wastewater polluted by phenol, the research of the thermodynamics of phenol adsorption on the adsorbent was very important. In this paper, a type of crosslinking starch microsphere (SM) has been synthesized by reversed phrase suspension method with soluble starch as raw material and N, N’-methylenebisacrylamide as crosslinking agent. And then the adsorption thermodynamics of SM toward phenol had been studied, and the adsorption capacity increased with the increasing of concentration of phenol solution, lower temperature ccould accelerate adsorption. The research results showed that the adsorption process was exothermic, could proceed spontaneously, and the adsorption driving force came from the enthalpy change mainly. The thermodynamic parameters of adsorption process showed that the adsorption behavior of SM towards phenol belongs to physical adsorption.

Abstract: Hydrogen is an important industrial raw material now and may become the main fuel in the future with increasing attention on the global warm and environment protection. Sorption-enhanced steam methane reforming (SESMR) integrates methane reforming, water-shift and CO₂ separating in one step and hydrogen concentration is high up to 98%. This paper reviews recent studies on the reaction kinetics about SESMR process. Microkinetics is believed the more promising and reliable than that of intrinsic kinetics. It is appropriate approach to promote carbonation rate through adding materials with a low melting point to the sorbent.

Abstract: Cellulose is one of the main components of renewable lignocellulosic biomass. Functional cellooligosaccharides obtained from the hydrolysate of cellulose could be used as model compounds to study the chemical reactivity of cellulose. HPLC, 1H NMR and 13C NMR techniques were used to analyze the degradation products of cellotriose and cellotetraose oxided by hydrogen peroxide. Results demonstrated that the main degradation products were oligosaccharides with lower degree of polymerization (DP), glucose, and other products including polyhydroxy acid and ketone. The degradation rate declined with the increment of DP. The degradation of cellotriose and cellotetraose at 60 °C followed a pseudo-first-order rate law, the degradation reaction rates were k3=0.25 h-1 and k4=0.15 h-1. Cellooligosaccharides could be degraded completely at higher temperature and for longer reaction time. Degradation products were also degraded at higher temperature and for longer time. The concentration of degradation products went up with the increase of substrate concentration.

Abstract: Whereas inorganic salt hydrates are typical inorganic phase change materials suitable for the temperature range of 0-150°C, their investigation and applications on thermal energy storage have received more and more during the recent years. A review on investigation progress and applications of their phase transition temperature control and adjustment was made in this paper, which is of important reference and practical value for understanding and predominating the investigation and engineering applications on their phase transition temperature control and adjustment.

Abstract: Soil microbe’s response to coarse woody debris (CWD) was assessed in two contrasting stands. The volume, percent cover and weight of CWD in the damaged stand were significantly much higher than the undamaged stand. Redundancy Analysis showed that CWD and soil nutrient had a significant effect on soil microbial community (p < 0.005). Decay class of CWD had the greatest influence on soil microbial communities, and soil nutrient was next to it. With increasing decay class, CWD was favorable for soil microbial functional diversity. Alkali-hydrolyzable nitrogen, available phosphorus and available potassium showed a positive correlation with decay class and made a positive contribution on soil microbial functional diversity. Stands without ice storm impact temporarily had higher soil nutrient content than those suffered severe damage at the early stage after ice storm. Soil microbial functional diversity had no difference between both slopes. Findings reflected that there were other factors affecting the soil microbes in forest ecosystem except for the CWD decomposition and soil nutrient.

Abstract: With isophorone diisocyanate (IPDI) and polyether diols (N210) as raw, the water-borne polyurethane was synthesized. The end groups of the water-borne polyurethane were blocked with 2-hydroxyethyl acrylate (HEA). The chemical structures were characterized from Fourier Transform infrared spectroscopy (FTIR). The viscosity of the emulsion was investigated from rotary viscometer. The kinetics of reaction of NCO blocked with HEA was investigated, the results show that the reaction fits to a second-order reaction characteristic and the reaction rate is irrelevant with HEA.