不同材质对催化裂化装置催化剂粉尘粘附性能的试验研究

在三座DN150 mmX1600 mm有机玻璃塔试验装置上,考察了DN15的塑料拉西环、陶瓷拉西环和不锈钢拉西环三种材质填料对催化剂的粘附能力。在催化剂浓度5‰,液相负荷40 L/h,气相负荷80 m3/h的条件下,经过408h的连续运转,结果表明不同材质填料对催化剂的粘附能力均存在饱和状态,粘附在填料上的催化剂不随时间的持续增加而增多。其中,塑料填料对催化剂的粘附能力最强,增重0.125kg;不锈钢填料次之,增重为0.115kg;陶瓷填料最弱,增重为0.055kg。可为相关领域的工业应用提供借鉴和数据支撑。     

我国工业固体废物的产生特征及控制对策

工业固体废物是固体废物的重要组成部分。根据我国最近10年发布的工业固体废物统计数据,全面分析了我国工业固体废物的产生特点,研究了工业固体废物产生量、利用量和处置量、工业固体废物区域和行业分布特点以及与工业产值的关系,并针对我国工业固体废物管理存在的问题,提出了相应的对策和建议。     

地质雷达在监测地下水石油烃污染中的应用

随着我国工业迅速发展,石油烃污染威胁地下水安全问题逐渐暴露出来。地质雷达作为一种非破坏性的原位探测技术在国外已广泛应用于地下水监测,由于石油烃在地质雷达图谱上通常显示出高阻异常特征,这为探测地下水中的石油烃污染提供了可能。简述了地质雷达探测石油烃的原理,探测效果的影响因素,并列举了部分国外实例,证实了地质雷达探测地下水石油烃污染的可行性。     

明胶厂剩余高钙污泥作为燃煤固硫剂的应用研究

明胶生产产业在废水处理工艺中产生大量剩余高钙污泥,采用该剩余污泥作为燃煤固硫剂,在高温管式电阻炉内进行燃烧实验,通过测定燃烧前和燃烧后样品中的硫含量确定该剩余污泥的固硫效果。通过单因素研究煤粉粒径、剩余污泥粒径和剩余污泥/煤样%等影响因素对固硫率的影响。在单因素试验的基础上通过正交设计法优选达到较高固硫率的实验条件。实验结果表明:影响固硫率的因素从大到小依次为燃烧温度>剩余污泥/煤样%>煤粉粒径>剩余污泥粒径。以剩余污泥作为固硫剂,固硫率最高的实验条件为:燃烧温度800℃,剩余污泥/煤样为3%,煤粉粒径60⁹0目,剩余污泥粒径9090目,剩余污泥粒径90¹20目。并且,当温度达到1150℃,煤粉粒径90120目。并且,当温度达到1150℃,煤粉粒径90¹20目,剩余污泥粒径为60120目,剩余污泥粒径为60⁹0目,污泥/煤样(质量比)为3%时,固硫率可达62.78%,说明在高温下该剩余污泥保持较高的固硫率。将明胶厂剩余污泥作为固硫剂是较为合适的再利用方法,可有效缓解当前该污泥大量堆积污染环境的状况。     

Pb(II) removal from water using Fe-coated bamboo charcoal with the assistance of microwaves

Bamboo charcoal(BC) was used as starting material to prepare iron-modified bamboo charcoal(Fe-MBC) by its impregnation in FeCl 3 and HNO 3 solutions simultaneously,followed by microwave heating.The material can be used as an adsorbent for Pb(Ⅱ) contaminants removal in water.The composites were prepared with Fe molar concentration of 0.5,1.0 and 2.0 mol/L and characterized by means of N 2 adsorption-desorption isotherms,X-ray diffraction spectroscopy(XRD),scanning electron microscopy coupled with energy dispersive X-ray spectrometry(SEM-EDS),Fourier transform infrared(FT-IR) and point of zero charge(pH pzc) measurements.Nitrogen adsorption analyses showed that the BET specific surface area and total pore volume increased with iron impregnation.The adsorbent with Fe molar concentration of 2 mol/L(2Fe-MBC) exhibited the highest surface area and produced the best pore structure.The Pb(Ⅱ) adsorption process of 2Fe-MBC and BC were evaluated in batch experiments and 2Fe-MBC showed an excellent adsorption capability for removal Pb(Ⅱ).The adsorption of Pb(Ⅱ) strongly depended on solution pH,with maximum values at pH 5.0.The ionic strength had a significant effect on the adsorption at pH < 6.0.The adsorption isotherms followed the Langmuir isotherm model well,and the maximum adsorption capacity for Pb(Ⅱ) was 200.38 mg/g for 2Fe-MBC.The adsorption processes were well fitted by a pseudo second-order kinetic model.Thermodynamic parameters showed that the adsorption of Pb(Ⅱ) onto Fe-MBC was feasible,spontaneous,and exothermic under the studied conditions,and the ion exchange mechanism played an significant role.These results have important implications for the design of low-cost and effective adsorbents in the removal of Pb(Ⅱ) from wastewater.     

Adsorption of 2-mercaptobenzothiazole from aqueous solution by organo-bentonite

The adsorption behavior of 2-mercaptobenzothiazole onto organo-bentonite was investigated.Natural bentonite from Gaozhou in Guangdong Province,China was collected.Organo-bentonite was prepared by intercalation of cetyltrimethyl ammonium bromide into the natural bentonite.The physicochemical properties of the prepared organo-bentonite were characterized by X-ray diffraction,N2 adsorption-desorption isotherm and Fourier transform infrared spectroscopy.The results showed that montmorillonite is the main component of the natural bentonite.The basal spacing of the natural bentonite is 1.47 nm,which increased to 1.98 nm on intercalation with cetyltrimethyl ammonium bromide.Moreover,both the surface area and pore volume increased with intercalation.Clear CH2 stretching(3000-2800 cm-1) and scissoring(1480-1450 cm-1) modes of the intercalated surfactants were observed for organobentonite.Compared with the pseudo first-order kinetic model,the pseudo second-order kinetic model is more suitable to describe the adsorption kinetics of 2-mercaptobenzothiazole onto organo-bentonite.The adsorption capacity of 2-mercaptobenzothiazole onto organo-bentonite increased with increasing initial concentration of 2-mercaptobenzothiazole,but decreased with increasing adsorbent dosage.The adsorption isotherm of 2-mercaptobenzothiazole onto organo-bentonite fits well with the Langmuir model.The maximum adsorption capacity of organo-bentonite for 2-mercaptobenzothiazole was 33.61 mg/g,indicating that organo-bentonite is a promising adsorbent for 2-mercaptobenzothiazole.     

Removal of Cd2+ from water by Friedel’s salt (FS: 3CaO.Al2O3·CaCl2·10H2O): Sorption characteristics and mechanisms

The development of low-cost and efficient new mineral adsorbents has been a hot topic in recent years. In this study, Friedel’s salt (FS:3CaO·A12O3 ·CaCl2 ·10H2O), a hexagonal layered inorganic absorbent, was synthesized to remove Cd2+ from water. The adsorption process was simulated by Langmuir and Freundlich models. The adsorption mechanism was further analyzed with TEM, XRD, FT-IR analysis and monitoring of metal cations released and solution pH variation. The results indicated the adsorbent FS had an outstanding ability for Cd(Ⅱ) adsorption. The maximum adsorption capacity of the FS for Cd(Ⅱ) removal can reach up to 671.14 mg/g. The nearly equal numbers of Cd2+ adsorbed and Ca2+ released demonstrated that ion-exchange (both surface and inner) of the FS for Cd(Ⅱ) played an important role during the adsorption process. Furthermore, the surface of the FS after adsorption was microscopically disintegrated while the inner lamellar structure was almost unchanged. The behavior of Cd(Ⅱ) adsorption by FS was significantly affected by surface reactions. The mechanisms of Cd2+ adsorption by the FS mainly included surface complexation and surface precipitation. In the present study, the adsorption process was fitted better by the Langmuir isotherm model (R2 = 0.9999) than the Freundlich isotherm model (R2 = 0.8122). Finally, due to the high capacity for ion-exchange on the FS surface, FS is a promising layered inorganic adsorbent for the removal of Cd(Ⅱ) from water.     

Enhanced photocatalytic activity of quantum-dot-sensitized one-dimensionally-ordered ZnO nanorod photocatalyst

An efficient photocatalyst was fabricated by assembling quantum dots （QDs） onto one-dimensionally-ordered ZnO nanorods, and the photocatalytic properties for Methyl Orange degradation were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV-Vis-NIR absorption spectroscopy and photoluminescence. The results indicate that the catalyst with assembled QDs is more favorable for the degradation than the pristine ZnO nanorods. The QDs with core-shell structure lower the photocatalytic ability due to the higher carder transport barrier of the ZnS shell layer. Besides its degradation efficiency, the photocatalyst has several advantages given that the one-dimensionally-ordered ZnO nanorods have been grown directly on indium tin oxide substrates. The article provides a new method to design an effective and easily recyclable photocatalyst.     

Research on the evolvement of morphology of coking coal during the coking process

The evolvement of morphology and structure of the coal with different metamorphic degrees during coking process in the vertical furnace was investigated by infrared Image detector. Moreover, the temperature distribution in the radial direction and the crack formation were also studied in heating process. The results show that the amount of crack and the shrinkage level of char decrease with the coal rank rising. In addition, the initial temperature of crack formation for char increases with the coal rank rising.     

Interface-mediated synthesis of monodisperse ZnS nanoparticles with sulfate-reducing bacterium culture

We have created a new method of ZnS nanospheres synthesis. By interface-mediated precipitation method (IMPM), monodisperse ZnS nanoparticles was synthesized on the particle surface of sulfate-reducing bacterium nutritious agar culture. Sulfate-reducing bacterium (SRB) was used as a sulfide producer because of its dissimilatory sulfate reduction capability, meanwhile produced a variety of amino acids acting as templates for nanomaterials synthesis. Then zinc acetate was dispersed into nutritious agar plate. Subsequently agar plate was broken into particles bearing much external surface, which successfully mediated the synthesis of monodisperse ZnS nanoparticles. The morphology of monodisperse ZnS nanospheres and SRB were examined by scanning electron microscopy (SEM), and the microstructure was investigated by X-ray diffraction (XRD). The thermostability of ZnS nanoparticles was determined by thermo gravimetric-differential thermo gravimetric (TG-DTG). The maximum absorption wavelengh was analysed with an ultraviolet-visible spectrophotometer within a range of 199–700 nm. As a result, monodisperse ZnS nanoparticles were successfully synthesized, with an average diameter of 80 nm. Maximum absorption wavelengh was 228 nm, and heat decomposed temperature of monodisperse ZnS nanoparticles was 596°C.