Ceramic tiles with black pigment made from stainless steel
The major controlling leaching mechanism for Cr and Pb from the ceramic tiles is initial surface wash-off, while the leaching behavior of Cd, Ni, and Zn from the stabilized product is mainly controlled by matrix diffusion. The reutilization process is safe and effective to immobilize the heavy metals in the stainless steel plant dust.
MODELING CHROMIUM LEACHING FROM CHROMITE ORE
of land-disposal hazardous wastes. Haskök (1998) experimentally studied leaching rates of total Cr and Cr(VI) using laboratory columns packed with chromium COPW material produced by a sodium chromite plant. Based on the experimental results of Haskök (1998), present study aim, through mathematical modeling, to understand the dissolution iii
Structural and catalytic promotion of skeletal copper
Oct 19, 2004 · ZnO and Cr2O3 promoted skeletal copper catalysts have been prepared by leaching CuAl2 alloy particles in aqueous sodium hydroxide containing various concentrations of sodium zincate (Na2Zn(OH)4) (0–0.62 M), of sodium chromite (NaCrO2) (0–0.1 M) or of a mixture of sodium zincate (0.005 M) and sodium chromite (0.02 M). Both sodium zincate and sodium chromite in the caustic solution were ...
Bio)leaching Behavior of Chromite Tailings
In order to rule out chromite as a source of dissolved Cr, a leaching experiment with concentrated ore (product after the beneficiation plant) at pH 2, and a pulp density of 30 g/L, was performed . The results show three fold less Cr in the leachate of the concentrated ore sample (47 mg/kg) compared with the leachate of the fresh tailing sample ...
LEACHABILITY OF CHROME FROM MAGNESIA-CHROMITE REFRACTORY
of chromite and magnesia-chromite refractory bricks with reactive slag as Na 2 O-SiO 2 [1, 2, 5-8]. The dumping of this refractory debris is a serious problem, as it is a potentially hazardous waste to human health and all ecosystem, water, soil, plants and animals. The debris step by step disintegrates at the dump and
Caustic Leaching of Montana Chromite
with the amount of chromite corisumed in the United states. In 1948 the total domestic production was estimzted at 3,500 tons of metallure;ical-grade chr-omtt.e-o-ChrQl.lite having a chr-omer iron ratio of 3:l--whereas , the total consUJ:11ptionwas 380,000 tons. The il'lported ors, in decreasing order of receipts, cafle from the U.S.S.R.,
Gold ore Carbon-In-Leaching (CIL) processing technology
The ﬂotation tailings containing the unrecovered gold from the primary circuits are directed to the leaching plant and dissolved in an aerated sodium cyanide solution. The solubilized gold is simultaneously adsorbed onto coarse granules of activated carbon directly in the pulp in the so-called Carbon-In-Leach process (CIL).
Leaching Mechanisms of Cr(VI) from Chromite Ore Processing
Batch leaching tests, qualitative and quantitative x‐ray powder diffraction (XRPD) analyses, and geochemical modeling were used to investigate the leaching mechanisms of Cr(VI) from chromite ore processing residue (COPR) samples obtained from an …
Caustic Leaching of Montana Chromite - Digital Commons
Plant Corporation. Three mills were built which pro-duced 102,000 dry tons of chromite concentrates, but before the end of the war, Lmpor-te of chr-omtte from foreign countries were large enough so that wor-kon the ontana deposits was discontinued.8 Future Uses. With the developnent of cheap power froll1the nut erous ams which have been and are now
US3816095A - Method for recovering chromium values from
A method for recovering chromium values from chromite ore which initially involves pelleting a mixture of chromite ore and soda ash, preferably without the inclusion of recycled leached chromite ore residue or other refractory diluent, employing water, or preferably an electrolyte such as an aqueous solution of sodium hydroxide, potassium hydroxide, sodium aluminate, sodium silicate, sodium ...
Comparative study of alkali roasting and leaching of chromite
Oct 01, 2016 · Various processes such as soda-ash roasting (Antony et al., 2001), acid leaching (Geveci et al., 2002, Zhao et al., 2014), alkali leaching (Xu et al., 2005, Zhang et al., 2010) and alkali fusion (Hundley et al., 1985) have been developed for the processing of chromite ores in order to produce sodium chromate (Na 2 CrO 4), which is the primary ...
Will Cement Kill My Plants? | Home Guides | SF Gate
Acid loving plants prefer a pH of 5.0 to 5.5, ornamental plants and lawn grasses like a pH of between 5.8 to 6.5, as do vegetable plants. Also, water garden plants like a pH between 6.2 to 7.4.
PDF The process design of gold leaching and carbon-in-pulp
plant and/or full-scale plant. In the case of leaching and CIP/CIL, such data are relatively easy to obtain for existing plants, assuming that the problem is one of the design of an upgrade for an existing plant. In the case of a new plant, such data are much more difficult
Leaching of Valuable Elements from the Waste Chromite Ore
The efficacious treatment and resource utilization of the chromite ore processing residue (COPR) is important for chromate salt production. In this study, the leaching of valuable elements from the waste COPR was investigated. X-ray diffraction (XRD) analysis showed that the COPR mainly contained periclase (MgCr2O4), magnesiochromite ((Fe, Mg) (Cr, Fe)2O4), Fe (Cr, Al)2O4, and MgFeAlO4. The ...
Speciation and Recovery of Chromium From Chromite Ore
The results from this study indicate a need for efficient leaching methodologies in chromite ore processing plants to decrease the non-detrital fractions of chromium in the residue. Aggressive methodologies are required to recover chromium from the detrital fractions. The potential benefits of employing sodium peroxide for the complete recovery ...