Zinc arsenates

Metals in the platinum family are recognized for their ability to promote combustion at lowtemperatures. Other catalysts include various oxides of copper, chromium, vanadium, nickel, and cobalt. These catalysts are subject to poisoning, particularly from halogens, halogen and sulfur compounds, zinc, arsenic, lead, mercury, and particulates. It is therefore important that catalyst surfaces be clean and active to ensure optimum performance. 

Samples Analyzed by Inductively Coupled Plasma (ICP) Metals — Where two or more of the following analytes are requested on the same filter, an ICP analysis may be conducted. However, the Industrial Hygienist should specify the metals of interest in the event samples cannot be analyzed by the ICP method. A computer print-out of the following 13 analytes may be typically reported Antimony, Beryllium, Cadmium, Chromium, Cobalt, Copper, Iron, Lead, Manganese, Molybdenum, Nickel, Vanadium, Zinc. Arsenic — Lead, cadmium, copper, and iron can be analyzed on the same filter with arsenic. 

Zinc Arsenic trioxide See other NON-METAL oxides... 

After adjusting to 2 mol 1 1 in hydrochloric acid, 500 ml of the sample is adsorbed on a column of Dowex 1-XS resin (Cl form) and elution is then effected with 2 M nitric acid. The solution is evaporated to dryness after adding 1M hydrochloric acid, and the tin is again adsorbed on the same column. Tin is eluted with 2 M nitric acid, and determined in the eluate by the spectrophotometric catechol violet method. There is no interference from 0.1 mg of aluminium, manganese, nickel, copper, zinc, arsenic, cadmium, bismuth, or uranium any titanium, zirconium, or antimony are removed by ion exchange. Filtration of the sample through a Millipore filter does not affect the results, which are in agreement with those obtained by neutron activation analysis. 

Vos, G. and J.P.C. Hovens. 1986. Chromium, nickel, copper, zinc, arsenic, selenium, cadmium, mercury and lead in Dutch fishery products 1977-1984. Sci. Total Environ. 52 25-40. 

Immobilizing DENs within a sol-gel matrix is another potential method for preparing new supported catalysts. PAMAM and PPI dendrimers can be added to sol-gel preparations of silicas " and zinc arsenates to template mesopores. In one early report, the dendrimer bound Cu + ions were added to sol-gel silica and calcined to yield supported copper oxide nanoparticles. Sol-gel chemistry can also be used to prepare titania supported Pd, Au, and Pd-Au nanoparticle catalysts. Aqueous solutions of Pd and Au DENs were added to titanium isopropoxide to coprecipitate the DENs with Ti02. Activation at 500°C resulted in particles approximately 4 nm in diameter. In this preparation, the PAMAM dendrimers served two roles, templating both nanoparticles and the pores of the titania support. 

In the first epoch, the properties of metals were explored. New metals (zinc, arsenic, antimony, and bismuth) were discovered. The specific weights... 

The total cost to treat 2000 tons of mine waste contaminated with lead, zinc, arsenic, and mercury at a historic gold mine in Central City, Colorado, was 55,000. According to the vendor, Envirobond was applied ex situ at a total cost of approximately 20 per ton (D204808, p. 8 D20477D, p. 2 D20479F, p. 1). 

Only for a few organozinc compounds, in which in addition to the zinc-carbon bond a zinc-heteroatom bond other than oxygen or nitrogen is present, have structures in the solid state been determined. These structures include those of organozinc compounds in which, in addition to the zinc-carbon bond, a zinc-sulfur, zinc-selenium, zinc-phosphorus or zinc-arsenic bond is present. 

Zinc Ammonium Chloride Zinc Arsenate Zinc Borate Zinc Bromide... 

Zinc Arsenates.—Zinc Orthoarsenate, Zng(As04)2, has been obtained in the anhydrous form by heating zinc carbonate with aqueous arsenic acid to 200° C.6 or by fusing a mixture of zinc chloride and arsenic pentoxide.7 The latter process yields prismatic crystals of density 4-913 at 15° C. The trihydrate, Zn3(As04)2.3H20, is precipitated... 

Water-borne preservatives are divided into two categories. One group which includes acid copper chromate, chromated zinc chloride, copperized chromated zinc arsenate and fluorchrome-arsenate-phenol is used where the wood is not subjected to excessive leaching. The second group, ammoniacal copper arseuite and three types of chromated copper arsenate which react to become practically water insoluble, are used at about 0.6 lb/ft3 (9.6 kg/m3) when wood is placed in ground contact under severe service conditions. 

USA Virginia, New York, and Florida soils within distances of 300 mm from 19 utility poles coated with ammoniacal copper zinc arsenate preservatives <1 to 10.3 11.3 Morrell, Keefe and Baileys (2003)... 

Substantial arsenic may leach into adjacent soils from wooden structures with CCA or other arsenic-bearing preservatives. Townsend et al. (2003) has shown that 65 surface soil samples from underneath nine CCA-treated wood structures in Florida, USA, contain 1.18-217 mg kg-1 of arsenic when compared with control soils that average only 1.36 mg kg-1 (Table 3.20). In a study involving ammoniacal copper zinc arsenate wood preservatives, arsenic concentrations generally fell to background levels within 150-300 mm away from 19 utility poles in Virginia, New York, and Florida, USA ((Morrell, Keefe and Baileys, 2003) Table 3.20). The environmental effects of arsenic-bearing wood preservatives are further discussed in Chapters 5 and 7. 

Morrell, J.J., Keefe, D. and Baileys, R.T. (2003) Copper, zinc, and arsenic in soil surrounding douglas-fir poles treated with ammoniacal copper zinc arsenate (ACZA). Journal of Environmental Quality, 32(6), 2095-99. 

M. Barwick, W. A. Maher, Biotransference and biomagnification of selenium, copper, cadmium, zinc, arsenic and lead in a temperate seagrass community from lake Macquarie, NSW, Australia, Mar. Environ. Res., 56 (2003), 471-502. 

Table 12 Average bond lengths and bond angles for some structurally characterized organozinc compounds containing a zinc-phosphorus or zinc-arsenic bond...

SYNS ARSENIC ACID, ZINC SALT ZINC ARSENATE, BASIC... 

River Station Date Discharge Cond. pH SPM Vanadium Chromium Manganese Cobalt Nickel CoQper Zinc Arsenic Rubidium Strontium Cesium Barium Lead Uranium... 

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