城市污泥-膨润土颗粒吸附剂的制备条件对吸附Pb~(2+)的影响

本文以城市污水处理厂的剩余污泥及膨润土为原料制备颗粒吸附剂。通过振荡吸附实验,考察了城市污泥-膨润土颗粒吸附剂的制备方法及颗粒吸附剂在含Pb2+废水中的吸附特性。结果表明:当膨润土和城市污泥的质量比为4:6、颗粒粒径为1.2mm、焙烧温度为550℃、焙烧时间为2h时,吸附剂的比表面积可达20.17m2/g,对废水中的Pb2+的吸附效率可达92%以上。     

污水厂剩余污泥制备烟气脱硫吸附剂

以城市污水厂剩余污泥为原料,采用负载金属氧化物的方法进行改性制备烟气脱硫吸附剂,并进行了元素分析、孔结构、扫描电镜性质表征,采用热分析及傅里叶红外光谱法对污泥吸附剂在SO2-O2-H2O(g)-N2体系的吸附机理进行了探讨。结果表明,同时负载质量分数为5%的MnO2和质量分数为5%的MgO的吸附剂性能较好,污泥吸附剂以中孔和大孔结构为主,比表面积较小。在SO2入口质量浓度为2021.38mg/m3、O2质量分数为12%、H2O(g)质量分数为12%、气体流速为2.13m/min和温度为60℃的条件下,污泥吸附剂的脱硫效率为93.7%,吸附容量为99.3mg/g。氨溶液法再生效果较好,再生2次后,脱硫效率下降至93%,吸附容量为84.4mg/g。水蒸气存在时,复合氧化物的协同作用促进了对SO2的化学吸附。等温吸附过程可用Freundlich模型描述,吸附热值为78.4kJ/mol。固定床吸附模型的预测值与实验结果吻合较好。     

基于非线性拟合的污泥衍生吸附剂对铅子等温吸附特性研究

利用城市污水厂污泥制取污泥衍生吸附剂，对溶液中铅离子进行吸附实验，研究一定条件下的等温吸附特性。利用线性拟合和非线性拟合两种方法对等温吸附方程进行模拟，得到非线性拟合求得的模型参数比较可靠，同时得到Langmuir模型比Freundlich方程更适合于描述铅离子在污泥衍生吸附剂表面上的吸附行为。     

污泥/钛铁矿复合吸附剂的制备及其吸附Cr(Ⅵ)研究

以城市污水处理厂剩余污泥为原料,添加微量钛铁矿,采用氯化锌活化法制备复合吸附剂,并考察了其对含Cr(Ⅵ)废水的处理效果。研究表明:钛铁矿添加量1.5%、氯化锌浓度3 mol/L、固液比1∶2、活化温度550℃和活化时间40 min时,复合吸附剂碘吸附值可达523.24mg/g,比表面积为285.003 m2/g,相对于不添加钛铁矿的纯污泥吸附剂分别提高了27.95%和43.08%;吸附Cr(Ⅵ)废水研究表明,当pH为1.5、吸附剂用量为4 g/L、吸附时间为120 min时,吸附率可达99.17%,吸附量为12.4 mg/g。     

污泥焚烧中铅的形态转化及脱除的热力学平衡研究

利用热力学平衡模型预测了污泥焚烧过程中铅的形态转化和迁移规律, 并采用系统吉布斯自由能最小的原理对Al₂O₃, SiO₂, TiO₂和CaO 4种吸附剂吸附污泥燃烧中铅的效果进行了模拟计算. 探讨了痕量元素Pb与S, Cl的相互作用及S和Cl的存在对吸附剂与Pb反应的影响. 研究结果表明, 污泥焚烧中Pb的形态转化受到S, Cl及矿物质的影响较大. 有S存在情况下, Pb在低温条件下主要以固态PbSO₄存在, 温度较高时以气态PbO存在; Cl较易和Pb结合形成低沸点的金属氯化物而导致Pb的挥发, 并且Cl含量的增加会加速Pb的挥发. 4种吸附剂对污泥焚烧中Pb都有一定的脱除能力, 其中Al₂O₃可以在较宽温度范围对Pb进行捕集, 而CaO对Pb的化学吸附能力较差. 由于S, Cl与Pb有更强的反应性, 因此S, Cl的存在对吸附剂与铅的反应有抑制作用, 使有效吸附的温度范围变窄, 吸附效率降低, 甚至失去脱除Pb的能力, 并且Cl的影响大于S.     

钢渣与污泥协同资源化研究进展

钢渣和污泥作为传统大宗固体废弃物,始终面临处理成本高、回收利用率低等问题,但其内部含有大量可利用物质,具有较高的资源化利用价值,现已成为国内外的研究热点。为了提高钢渣与污泥绿色、高效、协同资源化利用,综述了近年来国内外钢渣在建筑、道路、水处理、农业等领域资源化利用的研究进展,立足固废无害化、减量化,从钢渣和污泥的资源化进行分析与总结,指出不同研究方法的特点和优劣,为固废资源化利用提供参考。并基于我国发展现状对钢渣与污泥资源化利用的未来发展方向进行了展望,以期为固废处理行业的良性发展提供一定的理论支撑。     

树脂填充聚醚砜纤维吸附剂对牛血清蛋白吸附性能的研究

重点研究树脂填充聚醚砜(PES)纤维吸附剂与模型蛋白质牛血清蛋白(BSA)之间的吸附与脱附行为.结果表明,蛋白质BSA在树脂填充PES纤维吸附剂中的平衡吸附过程较好地符合朗格缪尔吸附模型,树脂Lewatit CNP80ws填充PES吸附剂的最大吸附容量约为139mg BSA/g吸附剂.表面具有开孔结构的树脂填充PES纤维吸附剂的吸附速率较快,在不同结构纤维吸附剂中BSA的扩散系数在1·82×10-14~8·7×10-14m2/s范围内变化.另外,考察了BSA溶液的pH与洗脱剂等因素对吸附剂吸附与脱附性能的影响,研究结果对蛋白质的实际分离纯化具有重要的参考价值.     

污泥型煤技术处理污泥的基础研究Ⅰ. 制备废水污泥型煤工艺条件的研究

提出了粉煤与污泥共混压制型煤的方法 ,以实现污泥的洁净化、能源化处理。研究了不同成型条件 ,如成型压力、水份、不同污泥及混合比例等对污泥型煤性质的影响 ,并根据上述实验结果提出制备污泥型煤的优化工艺 ,给出了污泥与煤共成型的机理模型。结果表明 ,污泥添加的比例为 2 0～ 30 %之间 ,成型压力高于 2 0MPa时 ,型煤的抗压强度高于添加 1 0 %黄泥所制型煤的强度。由此得出污泥完全可以代替黄泥 ;污泥型煤的热值高于黄泥型煤 ,而且型煤的热值与污泥的种类有关。     

天然气吸附剂的开发及其储气性能的研究：Ⅰ.吸附剂制备与体积 …

报道了天然气吸附剂的基本制备技术,并采用体积法评定了吸附剂的储气性能。结果表明,采用作者开发的吸附剂制备工艺可获得性能优良的天然气吸附剂。以木质素为原料制备的粉状吸附剂,其比表面积可达２９１２ｍ＾２／ｇ,微孔体积可达１．４８ｃｍ＾３／ｇ,平均孔径为１．４８ｎｍ,堆密度为０．３０ｇ／ｃｍ＾３。在６．０ＭＰａ、２５℃下,天然气的吸附储存量可达到１４０Ｖ／Ｖ。天然气吸附剂的储气性能与其比表面,微孔数量,     

树脂填充EVAL纤维吸附剂的制备及其吸附性能表征

采用具有亲水性的乙烯-乙烯醇共聚物(EVAL)作为纤维吸附剂基质材料,粉末型Lewatit阳离子交换树脂CNP80ws为功能材料,采用可控相分离方法,制备了不同表面形态结构的树脂填充EVAL吸附剂.当使用外部液体调控相分离过程时,在纤维的表面形成了粗糙的开孔结构,并且随树脂的填充量提高纤维表面的粗糙度与开孔度有所提高.研究结果表明:树脂填充EVAL纤维吸附剂具有较大的吸附容量与较高的脱附率,其吸附容量不低于53.9mg BSA/g吸附剂(树脂填充量50%).     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.