After the leaching solution was treated, the concentrations of Cd2+ and Ni2+ can be reduced from: 1086mg/L and 15.4mg/L to: 0.56mg/L and 0.54mg/L respectively. The loss of Zn2+ in the solution is about 1%.
In the medium of H 2C 2O 4 H 2SO 4 gold in sulfurized minerals can be decomposed by 50 g/L of thiourea solution with 99.8% of leaching out efficiency for gold. Gold then can be concentrated by chromatography with CL P 204 resin and determined by spectrophotometry with crystal violet.
A novel activated fixed-bed Raney nickel catalyst for h ydrogenation of unsaturated organic compounds was prepared by extruding the Ni- Al alloy powder with pseudoboehmite as binding material, calcining the extrudate s in air at a high temperature and leaching out the aluminum with caustic soluti on.
Novel Fixed-bed Raney nickel catalyst for hydrogenation of unsaturated org anic compounds has been prepared by extruding the Ni-Al alloy powder with pseudo boehmite, calcining the extrudates in air at higher temperature and leaching out the aluminum with caustic solution.
A process for preparing forage-grade cupric sulfate from copper oxide ore containing arsenic was proposed. It includes copper oxide ore leaching with NH 3-(NH 4) 2SO 4 solution,separating heavy metals with (NH 4) 2S and removing arsenic with ferrous sulfate. The leaching conditions are researched and the mechanism for removing arsenic is analyzed.
The catalysis of metal ions has been studied in bacterial leaching with Thiobacillus ferrooxidans in extraction of copper and nickel from complex low grade Cu and Ni sulphide minerals. Some metal ions (Ag+, Hg2+, Co2+, Bi3+) promote the leaching rate significantly.
It was shown that using ethylenediamine 0.05 mol/L(pH=10) to soak out free copper oxidie, the bonded copper oxide was soaked out by H 2SO 4(0.9 mol/L) solution containing Na 2SO 3 and NH 4HF 2 and secondary sulfide copper by HCl(1.0 mol/L) solution containing thiarea.
Mass and thickness of coating for Zn and Mn double-coating steel wire are determined by FAAS,coating immersion adopt HCl and SbCl 3,contents of Zn and Mn can be determined in the same solution,the rate of recovery of Zn 2+ is 98.5%～101.2%,and Mn 2+ is 98.2%～102.3%,the relative error is less than 2.9%.
They are functionally interconnected processes in the soil nitrogen cycle that are involved in the control of long-term nitrogen losses in ecosystems through nitrate leaching and gaseous N losses.
In the circulating fluidized-bed combustion of coal, the content of selenium in ash from the chimney was reduced to one-fourth of its original value and that in leaching water from the chimney decreased by two orders of magnitude using lime.
The Mn/Ce serial catalysts were characterized by Brunauer-Emmett-Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma torch-atomic emission spectrometry (ICP-AES).
The metallic ion leaching is comparatively low (Mn>amp;lt;6.577 mg/L and Ce>amp;lt;0.6910 mg/L, respectively) in the CWAO process.
A two-step continuous flow leaching system consisting of an acidifying reactor and a leaching reactor was introduced to achieve the bioleaching of spent nickel-cadmium (Ni-Cd) batteries.
Corrosion of metal stents implanted inside an artery can have two adverse effects: (1) tissue reaction and possible toxic effects from the metal ions leaching out of the stent, and (2) loss of mechanical strength of the stent caused by corrosion.
The neutral red-doped interior maintained its high electron-activity, while the exterior nano-silica surface prevented the mediator from leaching out into the aqueous solution, and showed high biocompability.
Infiltrating rainwater, leaching out contaminants from oil lakes and products of combustion at ground surface, can reach the water table and contaminate the groundwater.
The bowl-shape of these doping ions makes them suitable as ionic recognition sites, and their bulky character is expected to prevent them from leaching out of the conducting polymer membrane.
Comparisons of simulated and actual NO-3-N profiles revealed tendencies in GOSSYM to overestimate NO-3-N leaching out of the effective rooting zone, resulting in simulated N stresses midseason.
The differential and integral characteristics of nonstationary glass leaching with the inclusion of relaxation phenomena are interpreted within the probabilistic approach on the basis of the wave diffusion model associated with random walk.
The release of carbon dioxide to the soil air by organotrophic aerobes leads to leaching with carbonic acid and soda salinization.
It is argued that carbonates were deposited at the boundary between the "soda continent", which emerged as a result of subaerial leaching with carbonic acid, and the ocean containing Ca2+.
Heap leaching with HNO3 and FeCl3 solutions provides the decontamination factor of about 3, and stepwise elution with stirring, 9.0±0.3 which increases with the number of leaching cycles.
Extraction of Gold from ores and concentrates by leaching with the use of cyanides and alternative reagents
Our experimental results clearly show that the slow breakdown of ascorbic acid during its separation on a paper partition chromatogram is mainly due to the presence of oxygen and such destruction may be completely prevented upon removal of the latter. A quantitative procedure employing filter paper-partition chromatography is described for the determination of ascorbic acid in plant and animal tissues, using a mixture of n-butanol and 4％ aqueous trichloroacetic acid solution as solvent (4:6, v/v). The chromatogram...
Our experimental results clearly show that the slow breakdown of ascorbic acid during its separation on a paper partition chromatogram is mainly due to the presence of oxygen and such destruction may be completely prevented upon removal of the latter. A quantitative procedure employing filter paper-partition chromatography is described for the determination of ascorbic acid in plant and animal tissues, using a mixture of n-butanol and 4％ aqueous trichloroacetic acid solution as solvent (4:6, v/v). The chromatogram is developed in an atmosphere of carbon dioxide with a few per cent of hydrogen sulfide. The average recovery of added ascorbic acid is about 98％. Due to the irregularity in the percentage reduction of dehydroascorbic acid in the chromatographic chamber in the presence of H_2S, the procedure can only be used to determine the total content of ascorbic acid after preliminary reduction of the dehydro-compound.
From the alcoholic extract of the Bai Hwa She She Zao (Oldenlandta pinifolia (All) K. Schum), β-sitosterol, ursolic acid were isolated. In the mother liquor of ursolic acid, the existance of three triterpenoids was demonstrated by means of paper chrmatography.
Following the work on gas lift reactor (Pachuca tank) for gas-liquid-suspended solid 3-phase reaction, multideck gas lift reactors have been developed. This type of reactor has many unique advantages such as achieving of counter-current operation between gas and slurry, decreasing of gas consumption and small amount of volatile component of liquid required to recovery from the exit gas.