Zero-valent iron doped carbons readily developed from sewage sludge for lead removal from aqueous solution

Low-cost but high-efficiency composites of iron-containing porous carbons were prepared using sewage sludge and ferric salts as raw materials. Unlike previous time- and energy-consuming manufacturing procedures, this study shows that pyrolyzing a mixture of sludge and ferric salt can produce suitable composites for lead adsorption. The specific surface area, the total pore volume and the average pore width of the optimal composite were 321 m²/g, 0.25 cm³/g, and 3.17 nm, respectively. X-ray diffraction analysis indicated that ferric salt favored the formation of metallic iron, while Fourier transform infrared spectroscopy revealed the formation of hydroxyl and carboxylic groups. The result of batch tests indicated that the adsorption capacity of carbons activated with ferric salt could be as high as 128.9 mg/g, while that of carbons without activation was 79.1 mg/g. The new manufacturing procedure used in this study could save at least 19.5 kJ of energy per gram of activated carbon.     

功能化多孔材料对CO_2的吸附分离研究进展

功能化多孔材料拥有优越的CO_2吸附和存储性能,在燃煤电厂、玻璃炉窑、水泥厂、钢铁厂等高耗能工矿企业采用CO_2吸附技术,对CO_2减排、减缓温室效应具有重要意义。随着研究的不断深入,新型CO_2吸附材料呈现出廉价、易获取、高吸附率等趋势,当前研究重点集中在介孔硅、金属有机框架、沸石、活性炭、聚合物等的表面功能化。总结了上述典型吸附剂功能化的最新成果,重点介绍多孔吸附材料的功能化方法、吸附机理与吸附动力学的研究进展,并提出多孔材料对CO_2的吸附分离的研究空间和发展趋势。     

机动船含油废水处理方法研究

以羟基膦酸钠盐和聚合氯化铝为絮凝剂,对模拟机动船含油废水进行絮凝,使该废水中的乳化油颗粒与絮凝剂形成絮状物而与水相分离,然后再利用超微孔聚氨酯复合材料过滤分离,测得过滤后水相中含油量为2.12 mg/L,低于<船舶污染物排放标准>(GB 3552-83)的排放限值(15 mg/L).这种以羟基膦酸钠盐和聚合氯化铝为絮凝剂、超微孔聚氨酯复合材料为过滤材料的方法,比使用其他絮凝剂、破乳剂和过滤方式的方法效果更好.     

曝气器工业化性能测试研究

对7种曝气器产品分别进行了单盘耐用性生产试验、单盘清水充氧性能试验以及对在大生产试验期间的服务面积、供气量、阻力变化、停气后阻力变化、曝气强度等方面进行了测试对比工作。试验表明,中微孔曝气器的各种性能指标明显优于大孔曝气器,可显著提高混合液中氧的吸收率。     

多孔钛板负载Pd-Cu阴极电催化还原饮用水中硝酸盐的研究

研究了以多孔钛板负载钯-铜(4∶1)合金作为阴极,通过电催化还原脱除饮用水中硝酸盐氮的效果和主要影响因素.试验表明,电催化反硝化的主要产物为氮气,钯-铜合金的电催化活性可达到16.69 mg/(g·h)、选择性可达96.9%.在低硝酸盐氮浓度下,电催化反硝化反应符合表观一级反应动力学,高浓度时符合零级反应动力学.当槽压低于1.5V或电流强度小于5mA时,阴极几乎不会发生硝酸盐氮的还原反应;而当槽压大于4.2V时或电流强度大于30mA时,阴极生成氨氮的副反应显著增加.中性条件下电催化反硝化的活性和选择性都能达到较好的效果,酸性条件下反应活性增加但选择性降低.溶液中的传质对反硝化没有显著影响.溶液中存在的其它阴离子对反硝化不利,不同阴离子对反硝化反应的影响次序为ClO₄^-3^--.     

应用多孔陶瓷滤料治理环境污染

综述多孔陶瓷的类型与特性、制备的原料与方法以及表征多孔陶瓷孔特性的参量;研讨多孔陶瓷在环境污染治理中的应用和原理;简介笔者正在研究的轻质多孔陶瓷滤料、表面改性陶瓷滤料。采用多孔改性陶瓷滤料,结合聚结过滤和光催化技术,分别处理油田开采水和有机污染废水,其中的试验结果显示,聚结过滤工艺对油和悬浮物的去除率分别达到了90%和96%以上,出水水质能达到含油废水回注水的国家A1标准。从而拓展了陶瓷滤料的应用领域。     

DYNAMIC FLUID LOSS DURING VISCOUS FLOW THROUGH A POROUS VERTICAL SLOT1

ABSTRACT. An experimental study of two-dimensional viscous flow through a vertical slot with one highly resistant porous wall was made. The fluid loss area of the porous wall was divided into five sections. The fluid loss rate for the various subareas was measured as a function of the bulk flow rate through the slot and the viscosity of the fluid. Static flow tests through the porous media were also conducted for each fluid viscosity. The results indicate that the experimental data can be correlated in terms of the difference between the static flow rate and the dynamic fluid loss rate as a function of the bulk Reynold's number and the bulk flow rate. Stream function profiles were determined for each experimental run to visualize flow through the length of the slot. An empirical correlation was developed between the superficial entrance width, δ, and the ratio of bulk Reynold's number to the Reynold's number based on flow through the porous wall.     

多孔球形材料阻火抑爆性能影响因素数值模拟研究

为探究影响多孔球形材料阻火抑爆性能的主要因素,采用气体爆炸模拟软件FLACS建立多孔球形结构中湍流燃烧模型,对填充多孔球形材料后丙烷/空气预混气体燃烧爆炸过程进行数值模拟。研究结果表明:多孔球形材料能够有效衰减爆燃压力波、阻隔火焰传播,起到阻火抑爆作用,且压力波衰减程度和火焰阻隔效果与多孔球形材料的尺寸、孔径及填充密度密切相关。当多孔球形材料的直径为25 mm、孔径为3 mm、填充密度为20层时,压力波衰减程度最大,火焰阻隔效果最明显,说明直径和孔径越小,填充密度越大,材料的阻火抑爆性能越强。     

多孔材料对管道内甲烷-空气预混火焰传播的影响

为研究多孔材料对封闭管道内甲烷-空气预混气体火焰传播的影响,设计加工了横截面积为80 mm×80 mm的方形试验管道,运用自发光拍摄技术和动态压力传感器对甲烷-空气预混火焰在该管道内传播过程中形状变化和压力特性进行了实验研究。结果表明,在管道尾部放置3种不同材质的多孔材料时,其对爆炸压力均有一定的抑制作用,聚氨酯泡沫对管道内压力的衰减效果优于聚苯乙烯泡沫和自制泡沫材料。对压力曲线进行一次求导,得出了压力变化速率,结果与空管道实验相比,在放置多孔材料的管道内压力降低的速率更快,时间更短。     

Transesterification of Pistacia chinensis seed oil using a porous cellulose-based magnetic heterogeneous catalyst

In the present work, a novel cellulose-based porous heterogeneous solid acid catalyst encapsulation of ferriferous oxide (Fe₃O₄) and sulfonated graphene (GO-SO₃H) into cellulose to form composite porous microspheres catalyst (GO-SO₃H/CM@Fe₃O₄)was synthesized and evaluated for biodiesel production from Pistacia chinensis seed oil. The SEM, EDS and FTIR analysis revealed that the catalyst GO-SO₃H/CM@Fe₃O₄ owned stronger active sites and GO-SO₃H dispersed well in porous surface and inside of cellulose support. Under the optimum conditions, microwave-assisted transesterification process was carried out with the best catalyst amount, i.e. 5 wt% GO-SO₃H/CM@Fe₃O₄ (weight ratio of GO-SO₃H/cellulose), and conversion yield reached 94%. The prepared catalyst could be easily separated from reaction solution by extra magnetic field and reclaimed at least five runs.