二烷基亚砜—胺二元系从氰化物溶液中萃取金

研究了二烷基亚矾—胺从氰化物溶液中萃取金的反应中,亚矾和胺的化学结构以及萃取条件对萃金效果的影响。结果表明二烷基亚砜—仲胺体系在适当条件下可从较高pH(10～11)的氰化物溶液中有效地萃取金,并能与大多数共存金属元素达到很好的分离。此外,还具易于反萃的优点,是有应用前景的新型萃取体系。     

铂族元素的协同萃取

介绍协同萃取用于铂族元素富集与分离的进展状况。     

SPUA—202喷涂聚脲铺地材料的研制

以液化ＭＤＩ、ＭＤＩ－５０、聚醚多元醇、端氨基聚醚、胺类扩链剂为要原料,研制了一种用于防滑铺地材料的慢速固化型喷涂聚脲弹性体ＳＰＵＡ－２０２。讨论了多异氰酸酯类型、硬段含量、扩链剂类型和端氨基聚醚类型对弹性体性能及反应速度的影响。同时介绍了ＳＰＵＡ－２０２喷涂聚脲铺地材料的性能及应用领域。     

炼油厂高标溶剂油类别优选研究

通过蒸馏实验对某炼油厂提供的各种石脑油的馏分范围进行测试,并用气相色谱仪对其化学组成进行详一细分析,结果表明抽余油具有制备低芳烃6号溶剂油的物质条件。实验与模拟计算表明：该抽余油经催化加氢分馏可制得芳烃〈10mg/L、d硫〈0．5mg/L的6号溶剂油;对该6号溶剂油进一步精馏则可制得纯度为99%的异己烷和纯度为98％的己烷两种高标溶剂油。与常规溶剂油及D系列溶剂油相比,正已烷价格与石脑油平均差价高达4000元/吨,且差价稳定,因此以抽余油生产正已烷/异己烷可获良好的经济效益。     

Alkali-assisted coal extraction with polar aprotic solvents

Coal extraction experiments were conducted using a coal, containing ca. 10% ash, from the Tshikondeni mine in South Africa. This coal dissolves only to a limited extent in pure polar aprotic solvents such as dimethylformamide (DMF) and N-methyl-2-pyrrolidinone (NMP). However, the addition of a strong base, e.g. sodium hydroxide (NaOH) or sodium tert-butoxide increased the degree of coal dissolution in these organic solvents. Depending on the extraction conditions, carbon extraction efficiencies of up to 90% were obtained. Carbon precursor material was recovered from the solution as a gel by precipitation with water. Ash content was reduced from 10% in the coal to less than 1.6% in the coal extracts. Sodium sulfide (Na₂S) addition further reduced ash content and aided the recovery of carbon precursors that led to graphitizable cokes but the degree of extraction was significantly reduced.     

溶剂法合成2-羟基-3-萘甲酸技术进展

介绍了国内外溶剂法生产２－羟基－３－萘甲酸的进展情况,并推荐采用溶剂法规模化生产２－羟基－３－萘甲酸     

Supercritical carbon dioxide extraction of triglycerides from Jatropha curcas L. seeds

This study examines the effects of pressure, temperature and solvent to solid ratio (SSR) on extraction efficiency of triglycerides from powdered Jatropha seeds by using supercritical carbon dioxide extraction. Supercritical extractions were designed for pressures ranging from 250 to 350 bar, temperatures ranging from 313 to 333 K and SSR values ranging from 65:1 to 125:1. All values were selected using response surface methodology in order to determine their effects on the concentration of triglycerides from the extracted oil. Using 3750 g of carbon dioxide over 5 h, a supercritical carbon dioxide extraction (at 350 bar, 333 K and an SSR value of 125:1) yielded 43.51% oil. The concentration and extraction efficiency (i.e. recovery) of triglycerides in the extract reached 657.1 mg/g and 97.62%, respectively. Changes in pressure presented more effective in increasing the recovery of triglycerides, but both temperature and the SSR value are important in obtaining high concentration of triglycerides from the Jatropha seeds that are useful for biodiesel materials.     

Solvent extraction of molybdenum from acidic leach solution of Ni–Mo ore

A P204(D2EHPA) diluted with sulfonated kerosene was used for the selective extraction of molybdenum from an acidic Ni–Mo ore leach solution that was reduced using sodium thiosulfate. The results indicate that P204(D2EHPA) is an effective extractant for the extraction of molybdenum. The extraction of Mo is more than 90 % at pH of 0.5, contact time of 10 min, and organic-toaqueous phase(O/A) ratio of 1:1 with 10 vol% P204(D2EHPA). Molybdenum in the loaded organic phase can be effectively stripped with ammonium acid carbonate solution, and the stripping of molybdenum with 60 g L-1 ammonium acid carbonate solution is 94.67 % at O/A ratio of 2:1 and contact time of 10 min.     

Kinetics and Thermodynamics of Oil Extraction from Olive Cake

The kinetics of oil extraction from olive cake by using ethanol 96% was studied for different solvent-to-solids ratios and temperatures. The thermodynamic aspect of the extraction process was also examined. In the kinetic study, the results produced by the model of So and Macdonald (a model involving two main mechanisms of oil extraction: a washing process and a diffusion process with two stages) were found to be in good agreement with the experimental data. The yield of oil in the extract increased with increasing contact time, solvent-to-solids ratio and extraction temperature. The calculated values of the mass transfer coefficients of various stages of the extraction were found to increase linearly with solvent-to-solids ratio and temperature. In all cases, the predominant mechanism in the extraction was the washing of the oil occurring on the particle surface. The values of the activation energy were 8.56 kJ mol⁻¹ for the washing stage, 9.88 kJ mol⁻¹ for the first stage of diffusion and 17.55 kJ mol⁻¹ for the second stage of diffusion by changing temperature from 20 to 50 °C. Further, the results obtained from thermodynamic study of extraction process gave positive values of enthalpy and entropy changes and negative values of change in free energy. Under the equilibrium conditions, the temperature coefficient was found to be 1.02.     

Solvent impregnated resins for the removal of low concentration phenol from water

The focus of this investigation is the development of a solvent impregnated resin for phenol removal from dilute aqueous solutions. Using a solvent impregnated resin (SIR) eliminates the problem of emulsification encountered in liquid–liquid extraction. Impregnated MPP particles and impregnated XAD16 particles are successfully used for phenol extraction. Impregnated MPP particles are preferred, as impregnated XAD16 particles show less mechanical strength and are more expensive. Impregnated MPP particles perform better compared to other synthetic adsorbents and basic ion exchangers. The maximum phenol capacity of impregnated MPP particles with 0.99 mol Cyanex 923 kg⁻¹ SIR is 4.1 mol kg⁻¹ SIR (386 mg g⁻¹ SIR) and of MPP particles containing 1.47 mol Cyanex 923 kg⁻¹ SIR it is 5.08 mol kg⁻¹ SIR (478 mg g⁻¹ SIR). The regenerability of impregnated MPP particles is easy and complete, and the particles are stable during several cycles. The equilibrium constants for the extraction of phenol are determined as K_chem = 37 L mol⁻¹ and K_phys = 18 (mol L⁻¹) (mol L⁻¹)⁻¹. With these values the SIR isotherms can be satisfactorily described.The results indicate that SIR technology is a promising alternative for the conventional phenol removal technologies at low phenol concentration levels.