Kinetic studies of dyes sorption from aqueous solutions onto the strongly basic anion-exchanger Lewatit MonoPlus M-600

The sorption of Tartrazine, Allura Red, Sunset Yellow and Indigo Carmine from aqueous solutions onto the strongly basic anion-exchanger (Lewatit MonoPlus M-600) of dimethylethanolamine functional groups and styrene–divinylbenzene matrix was investigated. The experimental data obtained at 50, 100, 200, 300 and 500 mg/dm³ initial concentrations at 20 °C were applied to the pseudo-first order, pseudo-second order and Weber–Morris kinetic models. The calculated sorption capacities (q_1,cal) and the rate constant of the first-order adsorption (k₁) were determined. The pseudo-second order kinetic constants (k₂) and capacities (q_2,cal) were calculated from the plots of t/q_t vs. t, 1/q_t vs. 1/t, 1/t vs. 1/q_t, q_t/t vs. q_t and 1/q₂ − q_t vs. t for type 1, type 2, type 3, type 4 and type 5 of the pseudo-second order expression, respectively.     

Sorption of palladium (II) chloride complexes on weakly, intermediate and strongly basic anion exchangers

The precious metals and their alloys are extensively applied in refineries and the chemical and electronic industries as well as in medicine. Their small amounts in nature and extensive exploitation from natural resources are a serious obstacle as far as their application is concerned. High prices of palladium favour its recovery from recyclable materials and industrial wastes. Ion-exchange chromatography is one of the physicochemical methods of noble metal ion recovery. A study was done on the possibility of selective removal of palladium (II) microquantities from the model 0.1-6.0 M HCl, 0.1-0.9 M HCl-0.9 - 0.1 M HNO₃, 1.0 M ZnCl₂ - 0.1 M HCl and 1.0 M AlCl₃-0.1 M HCl systems on weakly, intermediate and strongly basic anion exchangers. The sorption research of Pd (II) on various types of anion exchangers was carried out by means of dynamic and static methods. The working ion-exchange capacities, weight and bed distribution coefficients were calculated from the breakthrough curves of palladium (II) ions. From the static studies the recovery factors of Pd (II) depending on the anion exchanger-solution contact time in the model systems under discussion were determined.     

Removal of Congo Red dye from aqueous solution using Amberlite IRA-400 in batch and fixed bed reactors

Removal of Congo Red (CR) azo dye by adsorption process using Amberlite IRA-400 resin was evaluated in both batch and fixed bed system. From the batch adsorption results, maximum loading efficiency (99.99%) of CR dye was obtained at the conditions pH 4.5, temp. 303?K, contact time 180?min., Amberlite IRA-400 dose 0.5?g. The isotherm study ascertained on favorability of adsorption process as the value of separation factor (K_L?=?0.88) and Freundlich constant (1/n?=?0.96?R²?=?0.99) than Freundlich model (R²?=?0.97). The kinetic data studied at three different CR dye concentration (50, 75, 100?mg) and results were fitted with both pseudo-first-order and second-order model equations. The values of R² obtained are of 0.95 and 0.99 for former and later one, respectively, ensuring on best fitting of pseudo-second-order kinetics and also suggesting about the chemisorptions type of adsorption. The bed depth service model was applied for competitive analysis of the CR dye adsorption in column variables indicating mass transfer from aqueous solution to Amberlite IRA-400 phase. Fourier transform infrared analysis of CR-loaded resin Amberlite IRA-400 showed a band shifted from 1057 to 1130?cm^?1 confirming CR adsorption with Amberlite IRA-400. Scanning electron microscope analysis of resin before and after adsorption was well evident from the phase patterns. Selective separation of CR dye from waste effluent of a textile industry bearing CR dye along with other trace heavy metal was achieved.     

Studies of sorption of Pd(II) microquantities on strongly basic polyacrylate anion exchangers

The sorption of palladium(II) microquantities from a chloride and chloride-nitrate (V) model 0.1-6.0 M HCl, 0.1-0.9 M HCl-0.9-0.1 M HNO₃, 1.0 M ZnCl₂-0.1 M HCl and 1.0 M AlCl₃-0.1 M HCl systems on strongly basic polyacrylate anion exchangers was studied. The research was carried out by means of dynamic and static methods. The recovery factors of Pd(II) were determined from the static studies. The working ion-exchange capacities as well as weight and bed distribution coefficients of Pd(II) were calculated from the breakthrough curves. The commercial strongly basic anion exchangers of the functional quaternary ammonium groups — Purolite A-850 and Amberlite IRA-958 — can be used in recovery technologies of Pd(II) from anodic slime, wastewaters and spent catalysts due to their high selectivity.     

Electrochemical quartz crystal microbalance studies of a palladium electrode oxidation in a basic electrolyte solution

Anodic oxidation of Pd in basic solutions (0.1 M KOH_aq and 0.1 M NaOH_aq) has been examined via cyclic voltammetry (CV) and an electrochemical quartz crystal microbalance (EQCM). Admittance tests show that Pd(II) layer behaves as a rigid one. The anodic vertex potential influences mass response during formation of the Pd(II) layer. For low anodic vertex potentials, obtained absolute mass per mole values suggest Pd(OH)₂ or PdO·H₂O to be oxidation products. At this stage of the oxidation process, contribution from adsorbed H₂O/OH⁻ in Pd(II) layer formation could explain the lower-than-expected mass gain, although the extent of H₂O/OH⁻ adsorption is unclear. The mass gain decreases with further increase in the anodic vertex potential, eventually reaching the value of ca. 8 g mol⁻¹ at about 700 mV vs. SCE. Comparing the influence of vertex potential in CV experiments on the mass and reduction potential of the Pd(II) species points to the formation of PdO at higher oxidation potentials. At this stage of the process, a fraction of the PdO species is generated during transformation of previously formed Pd(OH)₂/PdO·H₂O. A shift of the main Pd(II) reduction potential peak depends on both the anodic vertex potential and on the composition of the Pd(II) film. The order of the Pd(II) reduction process is the opposite of that observed for the oxidation process. The Pd(IV) species formed at E ≥ 500 mV vs. SCE and those reduced between 50 and 350 mV are hydrated or contain hydroxyl groups.     

TAs-958常温石脑油脱砷剂的研制及工业应用

以廉价的硅 氧化物为主要原料开发的TAs-958常温石脑油脱砷剂具有常温常压使用,操作费用低,再生方法简单,可多次重复使用等特点,经小试,侧线试验和工业应用,结果表明,TAs-958常温石脑油脱砷剂可将石脑油中的砷有效地脱除至50ng/g以下,满足石脑油裂解制乙烯的要求。     

油气回收技术在铁路装车过程中的应用

轻质油品在装车（船）、储存、运输、等过程中存在着挥发损耗,挥发的油气受到装载、储存方式、运输工具、气温等因素的影响。介绍了直接冷凝法、吸附法、吸收法、膜分离法等4种油气回收的方法,阐述了油气回收技术在铁路装车过程中的应用。     

童氏图版在低渗透油田中的改进与应用

本文在童氏含水率与采出程度关系式的基础上,通过对统计系数和边界条件的修正,研究出符合低渗透油田的童氏改进图版,并在石南31油田实践应用中加以验证,改进后的曲线计算结果更加准确,更加符合油田具体实际。     

聚合物驱在提高油气采收率上的应用与进展

介绍了聚合物驱油原理,概括了聚合物驱所采用的聚合物品类,介绍了疏水缔合聚合物、两性聚合物及梳形聚合物的特点和发展概况,分析了提高采收率的系列方法。在新型驱油剂的研制过程中,要满足其苛刻的使用条件,开发出耐井下高温,不易在电解质溶液中被剪切破坏的高分子量聚合物驱油剂。     

Electrodeposition of palladium–silver in a Lewis basic 1-ethyl-3-methylimidazolium chloride-tetrafluoroborate ionic liquid

The electrodeposition of palladium–silver alloys was investigated in a basic 1-ethyl-3-methylimidazolium chloride/tetrafluoroborate ionic liquid containing Pd(II) and Ag(I). Cyclic voltammetry experiments showed that the reduction of Ag(I) occurs prior to the reduction Pd(II). Both electrodeposition processes require nucleation overpotential. Energy-dispersive spectroscopy data indicated that the composition of the Pd–Ag alloys could be varied by deposition potential and concentrations of Pd(II) and Ag(I) in the solution. The Pd content in the deposited Pd–Ag alloy increased with decreasing deposition potential and the Pd mole fraction in the plating bath. At potentials where the deposition of both Pd and Ag was mass-transport limited, the Pd/Ag ratio in the electrodeposited alloys was slightly less than the Pd(II)/Ag(I) ratio in the ionic liquid due to the smaller diffusion coefficient of Pd(II). Scanning electron micrographs of the electrodeposits showed that in general, the Pd–Ag alloys were nodular and become more compact upon increasing the temperature up to 120 °C.     

水气交替方法在GGY油田长6油层的应用

根据鄂尔多斯盆地GGY油田区域注水开发存在的问题开展的室内外注气实验,对水气交替驱油技术在该油田的应用进行了分析,并与现场实验相结合,提出对本区超低-特低渗透储层水气交替驱的一些初步认识。     

浅析甲醇回收的间歇蒸馏设计和应用

分析草甘膦生产中甲醇回收的间歇蒸馏设计,实地运用,指导甲醇工序的操作。     

轻烃回收工艺在油气田开发过程中的应用

在油气田开发过程中,大量井口伴生气、储罐烃蒸汽直接排放或通过火炬焚烧,造成环境污染,而且使伴生气不能得到有效利用,降低了油田开发的整体效益。通过轻烃回收处理,不但使油田大量伴生气得到了无害化处理,而且充分利用了资源,提高了经济效益。     

表面活性剂在膨润土改性中的应用与发展前景

根据表面活性剂的种类,将表面活性剂改性膨润土分为单阳离子有机膨润土、双阳离子有机膨润土、阴离子有机膨润土、阴-阳离子有机膨润土和非离子有机膨润土等5类;并对近几年来所研究的表面活性剂对膨润土改性的各种实验方法以及对改性膨润土所采用的表征手段、各类改性后膨润土的特征与吸附规律及应用进行了评述;同时展望了其未来可能的发展方向。     

碳纳米管在聚烯烃改性中的应用

综述了碳纳米管(CNTs)/聚烯烃复合材料的研究进展,评述了今后CNTs/聚烯烃复合材料的研究方向。CNTs对聚烯烃的力学性能、电性能和光学性能有促进作用：CNTs/聚乙烯复合材料的拉伸强度提高了约20%;ω(CNTs)为0.30%的CNTs/超高相对分子质量聚乙烯的体积电阻率小于1×10~9Ω·cm,达到了抗静电的要求,ω(CNTs)为0.01%的CNTs/聚乙烯薄膜的紫外线总透过率从67.5%降到32.0%。     

溶剂萃取在有机化合物提取和分离方面的应用（上）

回顾了溶剂萃取技术发展的历史。对于该技术在有机化合物提取和分离方面的研究和应用现状进行了综述。展望了未来的发展趋势。     

Transport properties of organic vapors in nanocomposites of organophilic layered silicate and syndiotactic polypropylene

Syndiotactic polypropylene (sPP) nanocomposites were obtained by melt blending synthetic fluorohectorite modified octadecyl ammmonium ions (OLS), and maleic-anhydride-grafted isotactic polypropylene (iPP-g-MA) as compatibilizer. The composition of the inorganic material was varied between 5 and 20 w/w%. Films of the composites were obtained by hot press molding the pellets. Melt-direct polymer intercalation of sPP into the OLS gave rise to nanocomposites in which the silicate layers were delaminated at low clay contents, and ordered to intercalated structures at the highest clay content. The elastic modulus was higher than for the pure polymer in a wide temperature range and increased with the inorganic content. The transport properties were measured for dichloromethane and n-pentane. The sorption was reduced compared to pure sPP. There were not significative differences between the samples having different inorganic contents. The diffusion coefficient decreased with increasing clay content. Permeability (P) showed a strong decreasing dependence on the clay content. The improvement of the barrier properties was largely caused by the reduced diffusion.     

碳酸钙在复合改性中的应用

无机填料碳酸钙在聚丙烯复合体系中的应用,研究了碳酸钙的加入对聚丙烯光学性能、分散性、力学性能中的冲击强度的影响,同时深入分析了无机填料对聚丙烯复合体系的增强增韧机理。     

Sorption and transport of methanol in poly(ethylene terephthalate)

This paper reports the sorption and diffusion characteristics of methanol vapor in polyethylene terephthalate (PET). Amorphous PET, semicrystalline, biaxially oriented annealed and non-annealed samples have been studied for equilibrium sorption and kinetics of methanol. At activities of methanol less than 0.30, uptake shows Fickian kinetics and isotherm follows the Dual Mode model. Diffusion coefficients increase with penetrant concentration and are of the order of 10⁻¹⁰ cm²/s. Hysteresis during desorption and increase in solubility during resorption suggest methanol induced conditioning effects which may have detrimental effects on the barrier efficacy of PET. At activities greater than 0.30, swelling and relaxation effects occur and the isotherms show Flory-Huggins behavior for all three samples. Uptake follows two-stage kinetics fit by the Berens-Hopfenberg model. Greater polymer chain stability due to annealing reduces the extent of relaxation and improves the barrier efficacy over amorphous and non-annealed, oriented PET. For amorphous PET, at 80% activity and above, an induction time is observed which is absent in the semicrystalline films, suggesting strong relaxation effects in the amorphous phase of PET.     

顶板垮塌在水溶采矿中的应用

在水溶采矿中应用矿层直接顶板的垮塌，可充分发挥该法的优点，提高岩盐等易溶于水矿物的采取率，延长矿区的寿命。