Performance improvement of a direct carbon solid oxide fuel cell via strontium-catalyzed carbon gasification

As a new way of power generation, direct carbon solid oxide fuel cells (DC-SOFCs) exhibit great potential in solution of energy crisis and environmental pollution. According to the working principle, the cell operation is a kinetically controlled process, and the reverse Boudouard reaction is the rate-determining step of the whole system. In this study, a Sr-based catalyst is successfully introduced to accelerate carbon gasification and thus enhance cell performance of DC-SOFCs. The electrochemical performance of DC-SOFCs operated on coconut active charcoal with various Sr loading contents (3 wt%–10 wt%), are studied and compared with that of DC-SOFCs with traditional Fe-catalyzed carbon fuel. Experimental results demonstrate that the best output of 316 mW cm⁻² is achieved from the single cell powered with 5 wt% Sr-loaded coconut active charcoal at 850 °C, higher than those of DC-SOFCs fueled by pure and 5 wt% Fe-loaded active charcoal. The superiority of the Sr-based catalyst is also demonstrated by the operation stability of the corresponding DC-SOFC, which displays a relatively long operation time of 22.68 h at 0.25 A cm⁻² with the fuel utilization of 18.3%. The SEM/EDX results indicate that the Sr-based catalyst exhibits good stability without agglomeration during cell operation at high temperature. In addition, the carbon gasification mechanism catalyzed by Sr-based catalyst is also proposed on the basis of these properties. This study indicates that the designed Sr-loaded coconut active charcoal is expected to be an alternative carbon fuel for DC-SOFCs.     

活性炭改性涤纶短纤维的研发及应用

将粉碎好的竹炭颗粒均匀地分散在聚酯切片中,纺制成具有吸附、抑菌等功能的活性炭改性涤纶短纤维。用该种纤维可以制成具有一定功能的毛巾、保暖内衣、袜子、床垫、口罩、工业滤材等产品,应用非常广泛。     

鲍鱼内脏酶解液抗氧化能力及脱腥工艺研究

以鲍鱼内脏粗蛋白为原料,使用木瓜蛋白酶为工具酶对其进行高效酶解,以水解度和抗氧化能力为指标,通过正交试验优化酶解工艺,得到最佳酶解工艺:p H 9,酶/底物([E]/[S])1 000 U/g,酶解温度60℃,底物浓度5%,此时酶解液DPPH自由基清除率为(88.14±0.92)%,水解度为(14.12±0.53)%;以食品级活性炭粉末为吸附剂,以蛋白质损失率和感官评价为指标,得到酶解液的最佳脱腥工艺为:活性炭的质量分数1.0%,吸附时间为60 min,吸附温度为50℃,在该条件下试验得到的蛋白质回收率为(88.06±0.24)%,腥味值为2.00。制备得到的酶解液具有较强抗氧化能力,脱腥液无明显苦腥味,液体澄清呈淡黄色,感官品质有了很大改善。     

Solid state 27Al NMR and X-ray diffraction study of alumina–carbon composites

The structural and chemical transformations occurring in alumina–carbon composites upon heat treatment were investigated by using a combination of X-ray diffraction (XRD) and solid-state ²⁷Al nuclear magnetic resonance (NMR) spectroscopy. Two different carbon precursors were employed: a commercial activated carbon and a char obtained by carbonization of the endocarp of babassu coconut at 700 °C. The alumina–carbon composites were prepared by aqueous impregnation of the carbon supports with aluminum nitrate and, after filtering and drying, the as-synthesized powders were heat-treated under argon flow at temperatures up to 1000 °C. The Al compounds present in the as-synthesized samples were identified by XRD and solid-state ²⁷Al NMR as nanocrystalline aluminum oxyhydroxides or hydroxides, depending on the synthesis conditions. All Al-containing phases were XRD-amorphous in the char-derived nanocomposites, with the presence of a distribution of AlO₆ (octahedral Al site), AlO₅ (pentacoordinated Al) and AlO₄ (tetrahedral Al site) units revealed by solid-state ²⁷Al NMR spectroscopy. The heat treatments caused the formation of transition aluminas dispersed over the carbon supports, with the occurrence of different amounts of AlO₆, AlO₅ and AlO₄ units depending on the heat treatment temperature and on the type of carbon precursor used for the preparation of the composites.     

生物质连续炭化工艺研究

利用自制螺旋炭化机,以生物质锯末为原料,采用连续炭化的生产工艺,分别研究了锯末炭化的停留时间和炭化温度,测试了不同炭化条件获得的炭粉样品组成和形貌.结果表明,在炭化温度达到450℃,停留时间20min以上的条件下,炭粉质量可以达到国标要求(GB/T 17664-1999).通过实验研究,优化了连续螺旋炭化的工艺参数和设备结构,为-亡业化设计提供了依据.     

竹炭改性泡沫炭材料制备及铜离子吸附性能研究

以酚醛树脂为基体前躯体,竹炭为添加剂,通过发泡、固化及炭化工艺制备出竹炭改性酚醛树脂基泡沫炭材料,研究了其对Cu2+的吸附性能,探究了竹炭含量、吸附时间和溶液pH值对泡沫炭材料吸附Cu2+效果的影响。结果表明:在竹炭含量为7%~10%、吸附时间45 min、溶液pH值为9的条件下,Cu2+的吸附效果最好,并且从微观结构上解释了其对Cu2+吸附能力曲线的变化趋势,解决了泡沫炭因孔径大而难以吸附重金属离子的问题,降低了制备成本,扩大了泡沫炭材料的应用范围。     

竹材制备SiC多孔陶瓷及吸波性能研究

以印度竹和竹炭粉为原料,采用溶胶凝胶法和液态渗硅法制备生物基SiC陶瓷块和陶瓷粉,并通过磁性金属担载制备了吸波材料。借助XRD、SEM、RAM反射率测试系统对材料的物相构成、微观构造、吸波反射率进行了分析。结果表明:竹材炭化及陶瓷化后均保持了多孔的骨架结构特征。溶胶凝胶法和液态渗硅法的陶瓷化反应都发生在竹炭孔道侧壁上,且溶胶凝胶法在竹炭孔道内部有硅基陶瓷晶须生成。要提高液态渗硅法竹炭向SiC的转化率和SiC的晶化程度,可以通过提高陶瓷化温度和延长保温时间的方法来实现。无论何种方法,竹炭粉比竹炭块的陶瓷转化率高。另外通过溶胶凝胶法制备的担载磁性金属的竹基陶瓷材料在低频波段有一定的电磁波吸收性能。草刺     

Use of activated charcoal for the purification of neon in the CLEAN experiment

Passage of neon gas through activated charcoal is planned to be the primary method of removing impurities from the liquid neon scintillator in the CLEAN experiment. In order to quantify this technique, the breakout curves for hydrogen, nitrogen, argon and krypton impurities in neon-saturated activated charcoal were measured. Adsorption coefficients and the number of theoretical stages were measured for hydrogen in the temperature range between 300 and 80 K, nitrogen between 300 and 200 K, and argon between 300 and 190 K. The adsorption coefficient for krypton was measured at 300 K.     

固体酸催化环己醇脱水制备环己烯

以活性炭、硅胶、石英砂、陶瓷球为载体负载甲烷磺酸,制得一系列负载型固体酸催化剂,用于催化环己醇脱水制备环己烯。结果表明,甲烷磺酸及不同载体的甲烷磺酸催化剂具有良好的催化活性;甲烷磺酸催化剂的催化活性与载体表面特性有关,载体为 TiO_2/陶瓷球和活性炭时,固载催化剂活性最高。在催化剂的焙烧温度为250℃,甲烷磺酸的浸渍浓度为0.8～1.0 mol/L,催化剂用量为醇总质量的15%条件下,环己烯的收率可达85%～90%。     

磷炉炭砖的腐蚀原因分析

分析了磷炉炭砖的腐蚀原因,认为炉壁厚度、炭砖的外形尺寸的大小及形状、填料的特性和性能变化以及炭砖砌体的性质、磷炉使用时炭砖的热膨胀、机械应力和热应力都是影响炭砖腐蚀程度的重要因素。