Cyanide ions transport from aqueous solutions by using quaternary ammonium salts through bulk liquid membranes

Extraction experiments were carried out to determine the suitable solvent and carrier type. Five different solvents and carriers were used and verified. Trichloromethane and tetraoctyl ammonium chlorides were found to be the most appropriate solvent and carrier type for this study. The coupled transport of cyanide ions in aqueous solutions through bulk liquid membrane (BLM) was investigated using various stirring speeds and temperatures. Cyanide ion transport through BLM technique was analyzed according to coupled non-steady state kinetics of two consecutive irreversible first order reactions. The influences of the kinetic parameters (k_1d, k_2m, k_2a, R_m^max, t_max, J_d^max, J_a^max) for the various stirring speeds in the system were established. The removal and recovery efficiencies of the cyanide ions transported from aqueous solutions in 360 min were 99.4 and 82%, respectively. As the stirring speed was increased, both the efficiency of transport and recovery of cyanide ions from aqueous solutions were increased. On the other hand, for maximum membrane entrance (J_d^max) and exit (J_a^max) fluxes the activation energies were calculated as 21.6 kcal/mol and 10.5 kcal/mol, respectively.     

Ecological Problems of Thermal Power Plants

The main legislative documents in the field of environmental protection and ecological standards for newly developed equipment of thermal power plants (TTP) of Russia are presented. Problems of raising the efficiency TTP and reducing harmful emissions are considered. Modern methods and process for lowering nitrogen oxide emissions for different kinds of fuel, fields of application of sulfur-removing technologies, and ways for updating fly-ash collectors are discussed. The tendency to tightening of standards regulating the volume of contaminating substances is shown. Data on TTP wastewaters and maximum permissible concentrations (MPC) of primary contaminants are presented. Reduction of atmospheric emissions and of contaminating due TTP wastewaters is estimated until 2010.__________Translated from Elektricheskie Stantsii, No. 1, January 2005, pp. 17–27     

高选择性脱除润滑油基础油中碱性氮化物 提高润滑油基础油的氧化安定性

采用武汉石油化工厂开发的ＷＳＱ－２脱氮剂专利技术能高选择性脱除润滑油基础油中碱性氮化物，脱碱氮率能达９０％以上，而硫化物的脱除率则很低。脱氮后基础油理化性质基本不变，而氧化安定性则有显著的提高。大庆石蜡基基础油脱碱氮后的旋转氧弹可达２００ｍｉｎ以上，南阳中间基基础油脱氮后的旋转氧弹可达２５０ｍｉｎ左右。     

降低聚酯生产中氮气消耗的工艺改进

针对聚酯生产用氮偏大的现状，分析了造成氮耗大的原因，对氮封装置氮气用量进行了工艺改进；在PTA卸料外氮管线安装了节流孔板，从而降低了氮气消耗，节约了生产成本。     

新型缓蚀杀菌剂双季铵盐在油田中的应用

从双季铵盐的结构、合成以及由其特殊结构所带来的奇特界面吸附(气/液、固/液界面吸附)特性和化学性质,阐述了新型缓蚀杀菌剂双季铵盐的缓蚀、杀菌机理和作为油田注水缓蚀杀菌剂的研究现状,同时论述了其在油田其它领域(如:驱油,含油污水浮选等)中的应用前景。     

Substantivity of sunscreens: an appraisal of some quaternary ammonium sunscreens

Two series of quaternary ammonium UV-B sunscreens, derived from salicylic acid (S) and from p -methoxycinnamic acid (C), and containing N-alkyl chains of different length (C₂ to C₁₆) were prepared and submitted to substantivity tests on animal (wool) keratin, and to microbiological tests. A direct correlation between substantivity and antimicrobial/antifungal activity was observed in all cases, the compounds bearing C₁₂ alkyl chains displaying peak values. The C-derivatives, when compared with the S-derivatives, showed relatively higher substantivity and sunscreen index (SI) values, coupled with lower antibacterial activity. The substantivity-microbiological activity correlations and the particular behaviour of the C₁₂ derivatives are briefly discussed in the light of the existing literature data. On the basis of the experimental results, possible guidelines for the development of substantive and non-antibacterial (and possibly, non-irritant) quaternary ammonium sunscreens are indicated.
La substantivité des filtres solaires     

The thermal conductivity of gases: Incorrect results due to desorbed air

Air desorbed from the measuring instrument can falsify the thermal conductivity of a gas measured by steady-state methods. For a guarded hot-plate apparatus the contamination effect was determined to depend on both the residence time in the system and the temperature. The investigation covered the gases H₂, He, Ne, CH₄, N₂, air, Ar, and Kr. For gases whose conductivity is better than that of air (H₂, He) the measured values are too small, and for gases of poorer conductivity they are too high. Corrections for the effect of impurity have been applied to the measurements presented. These impurity corrections are considerably larger than the precision of the measurements, but they are of the order of the estimated overall uncertainty of the measurements. The departures between the corrected thermal conductivities reported here and values taken from the correlations in the literature run up to 5 % at the highest temperatures.     

Theoretically based data assessment for the correlation of the thermal conductivity of dilute gases

This paper presents two schemes for a theoretically based data assessment of the thermal conductivity of dilute polyatomic gases. The first employs the simplified Thijsse expression, combined with accurate experimental data obtained from a transient hot-wire apparatus, as reference. The second makes use of theoretical results for the temperature dependence of the ratio D _int/D. Both methods lead to mutually consistent results for linear molecules and to useful criteria for discriminating between experimental data sets. The paper also demonstrates the influence of data burdened with systematic errors upon the final results of different correlation schemes.     

中国硝酸钾发展概况与市场前景

硝酸钾既是重要的工业原料,又是优质无氯钾、氮复合肥料,植物营养素钾、氮的总质量分数可达60%左右,是发展现代高效农业不可缺少的化肥品种。由于生产、市场、价格等方面的原因,目前硝酸钾在中国施用较少,而这种称为世界紧缺的"绿色钾肥"在欧洲国家较为盛行。伴随着高科技农业的不断发展,以及人们对食品安全要求的不断提高,中国市场对硝酸钾的需求将不断增加,不过目前这一市场仍表现出过于狭窄。简要介绍了硝酸钾的生产技术、中国硝酸钾生产发展现状、硝酸钾应用领域及市场前景,并对硝酸钾的发展提出了一些建议。     

用树脂回收钼酸铵生产废液中钼及有价资源的研究及生产实践

选用适当的树脂利用离子交换吸附的原理，回收钼酸铵生产过程中产生的酸性含钼废液中的钼金属，用稀氨水解吸饱和树脂，得到钼酸铵溶液，经净化除杂制得符合国标的钼酸盐产品；尾液进一步回收有价金属和铵盐，达到钼酸铵生产废液零排放和资源循环利用的预期目的。华县矿业焙烧厂实际运行两年，取得经济效益和环保效益双丰收。