Magnesium sulfate granulates contain at least 90 wt. % synthetic magnesium sulphate hydrate with respect to the total mass of the magnesium sulphate granulate, and have a dry loss of less than 2 wt. % determined by drying of the granulate for 2 hours at 105 C. and 1 bar. Further, a method is used for producing said magnesium sulfate granulates and to their use in urea-containing fertilizer compositions.

A filler composition comprising fibrous basic magnesium sulfate particles and non-fibrous inorganic micro-particles having an average particle diameter in the range of 0.001 to 0.5 m in a ratio by weight in the range of 100:0.001 to 100:50, is used for providing a molded resin product which shows impact resistance and rigidity balanced at a high level.

A filler composition comprising fibrous basic magnesium sulfate particles and non-fibrous inorganic micro-particles having an average particle diameter in the range of 0.001 to 0.5 m in a ratio by weight in the range of 100:0.001 to 100:50, is used for providing a molded resin product which shows impact resistance and rigidity balanced at a high level.

A hydrometallurgical process for the treatment of polymetallic ores and sulphide concentrates of copper and zinc, and by-products of lead and zinc from smelting plants, treated independently and/or as mixtures thereof, which contain relevant amounts of lead, copper, zinc, iron, gold and silver, such as the matte-speiss mixture of lead foundries, and copper cements from the purification processes of electrolytic zinc plants. The process allows the recovery of metallic copper, zinc, copper as copper and zinc basic salts, which may be hydroxides, carbonates, hidroxysulphates or mixtures thereof; the production of stable arsenic residues; and the effective and efficient recovery of Pb, Au and Ag as a concentrate of lead sulphide and/or lead, Au, and Ag sulphate.

A hydrometallurgical process for the treatment of polymetallic ores and sulphide concentrates of copper and zinc, and by-products of lead and zinc from smelting plants, treated independently and/or as mixtures thereof, which contain relevant amounts of lead, copper, zinc, iron, gold and silver, such as the matte-speiss mixture of lead foundries, and copper cements from the purification processes of electrolytic zinc plants. The process allows the recovery of metallic copper, zinc, copper as copper and zinc basic salts, which may be hydroxides, carbonates, hidroxysulphates or mixtures thereof; the production of stable arsenic residues; and the effective and efficient recovery of Pb, Au and Ag as a concentrate of lead sulphide and/or lead, Au, and Ag sulphate.

Magnesium sulfate granulates contain at least 90 wt. % synthetic magnesium sulphate hydrate with respect to the total mass of the magnesium sulphate granulate, and have a dry loss of less than 2 wt. % determined by diving of the granulate for 2 hours at 105 C. and 1 bar. Further, a method is used for producing said magnesium sulfate granulates and to their use in urea-containing fertilizer compositions.

Magnesium sulfate granulates contain at least 90 wt. % synthetic magnesium sulphate hydrate with respect to the total mass of the magnesium sulphate granulate, and have a dry loss of less than 2 wt. % determined by diving of the granulate for 2 hours at 105 C. and 1 bar. Further, a method is used for producing said magnesium sulfate granulates and to their use in urea-containing fertilizer compositions.

A novel process for treating and recovering valuable metals and other components from pickling acid residue (PAR) has been developed. The metals and other components are recovered by neutralizing the pickling acid residue using a magnesium compound or a mixture of magnesium compounds, and separating components of the resulting mixture (metals and sulfates) into products that can be reused, such as magnesium sulfate, nickel sulfate, iron and chromium phosphate, or various metal hydroxides or oxides.

A novel process for treating and recovering valuable metals and other components from pickling acid residue (PAR) has been developed. The metals and other components are recovered by neutralizing the pickling acid residue using a magnesium compound or a mixture of magnesium compounds, and separating components of the resulting mixture (metals and sulfates) into products that can be reused, such as magnesium sulfate, nickel sulfate, iron and chromium phosphate, or various metal hydroxides or oxides.

A forest fire retardant composition contains a retardant compound that includes a halide salt, a non-halide salt, a metal oxide, a metal hydroxide, a sulfate salt, or combinations thereof. The forest fire retardant composition may include at least one anhydrous salt and at least one hydrate salt. The sulfate salt may be magnesium sulfate. The magnesium sulfate hydrate has a formula MgSO.sub.4(H.sub.2O).sub.x, where x is about 1 to about 11. For example, x may be equal to at least one of 1, 2, 3, 4, 5, 6, 7, 9, 10 or 11. The composition may be in the form of a dry concentrate, a liquid concentrate, or a final diluted product. The final diluted product is effective in suppressing, retarding, and controlling forest fires while exhibiting corrosion resistance and low toxicity.