After the festival, the domestic rutile and anatase titanium dioxide new single price is stable, and the market new single transaction focus has moved up. Titanium dioxide factory work normally, more delivery of early orders, spot shipping pressure is small; And the buyer just needed to buy a few days ago. The volume of new orders in the market is limited.The key factors affecting the current market price change1. Inventory: the mainstream manufacturer inventory is low, there are still delivery orders after the holiday, it is expected that the spot inventory is still low today, and the mainstream factory spot is tight.
First, the ammonia leaching method is used as a technical means for the effective treatment of acid leaching slag, and the nano nitrite powder is prepared under a weak alkaline ( Ή 8 8.5 to 10) ammonia environment. In an alkaline environment, some metal impurities such as The solubility of Ca, Mg, Fe and Al hydroxides is low, and the impurities entering the final immersion liquid in the selective leaching of ammonia-ammonium sulfate are reduced, thereby ensuring the quality of the product; the traditional acid method for preparing lithopone is because of the zinc calcination. In the roasting and reduction process of the alkalized alkali, the elemental sulfur and sulfite are more or less produced, and the prepared white powder has a yellowish color, and the metathesis reaction of the patent is carried out in an ammonia solution (alkaline). The final product obtained is sulfate, which is quickly and thoroughly added by desulfurization through 3⁄40 2 , and the whiteness of the product can be ensured without high temperature calcination; the equipment requirement is lower than that of sulfuric acid leaching, and the ordinary steel leaching tank can complete the leaching; The environmental pollution problem of acid leaching residue, especially effectively solves the environmental pollution of heavy metals such as zinc, copper, lead, cadmium and arsenic in acid leaching residue and the influence of acid ions on the storage environment. Realize the recycling of high-value metal zinc in acid leaching slag, realize the acidity improvement of soil and have the comprehensive advantages of low cost, energy saving and environmental protection.
Having thus described the origin and uses of the pigment, we now come to the question, what is lithopone? It is, in short, a chemical compound usually consisting of 30.5 per cent zinc sulphide, 1.5 per cent zinc oxide and 68 per cent barium sulphate, but these proportions vary slightly in the different makes. Lithopone of this composition is sold as the highest grade, either as red seal or green seal, as it best suits the idea of the manufacturer. Many manufacturers, especially in Europe, sell and also export other brands under other seals, containing 24, 20, 18 and as little as 12 per cent of zinc sulphide with very small percentages of zinc oxide, the balance being usually barium sulphate, but sometimes certain portions of China clay or gypsum (calcium sulphate) or whiting (calcium carbonate). Such brands are not a chemical compound, but mechanical mixtures of the chemically compounded lithopone and the admixtures referred to.
Should a grade of lithopone be desired higher than the standard grade and another by-productas, for example, a forty-five*per= cent. grade of lithopone and barium chlorid the following process may be pi'acticed,\vhich, however, is quite analogous to the one already 10o described. Aqueous solutions of the ingredients are prepared as before, in these proportions: zinc sulfate, one hundred and sixty-one pounds; zinc chlorid, one hundred and thirty-six pounds, and barium sulfid, three hundred and thirty-eight pounds. Upon mixing these several solutions the lithopone will at once be precipitated in accordance with the following reaction: