Abstract: Methods for removing a soluble heavy metal-sulfur complex from a process solution comprise contacting the process solution with an oxidant to oxidize the heavy metal-sulfur complex and form an oxidized complex precipitate, or with an acid to acidify the heavy metal-sulfur complex and form an acidified complex precipitate, and removing the precipitate from the process solution to provide a heavy metal-reduced solution. The method is advantageous for removing heavy metals such as mercury, cadmium, barium, iron, vanadium and/or manganese from process solutions, for example originating from natural gas production, petroleum production, water treatment or mining.

Abstract: The present invention relates to an aqueous liquid fertilizer composition having a 4 wt % to 30 wt % nitrogen content and 8 wt % to 27 wt % sulfur content comprising more than 20 wt % ammonium thiosulfate, calculated as dry matter, and at least 2 wt %, calculated as dry matter, of one other compound selected from the group consisting of a sulfite, bisulfite, urea-triazone compound and zinc sulfate hexahydrate or mixtures thereof, wherein the composition has a salt out temperature of about 0 C or less as measured with the FFF-method. The aqueous liquid fertilizer composition of the present invention can have an amount of sulfur of about 21 wt % or higher, for example 22-26 wt %.

Abstract: The invention relates to a process for preparing potassium thiosulfate, potassium sulfite or potassium bisulfite comprising the following steps: Step (1a): providing a potassium hydroxide or potassium carbonate solution for neutralizing acid forming components such as dissolving SO2 or H2S; Step (1b): providing an SO2 contacting solution, containing at least some potassium sulfite or potassium bisulfite or potassium thiosulfate; Step (2): providing SO2 gas; Step (3): reacting these to absorb the SO2 gas and to form an intermediate reaction mixture comprising potassium sulfite, or potassium bisulfite or a mixture thereof, and optionally recovering the potassium sulfite, or potassium bisulfite or a mixture thereof, and/or optionally using steps 4 and 5; Step (4): adding sulfur or sulfide containing compound containing sulfur having the oxidation state of 0, ?2 or of between 0 and ?2 to the reaction mixture and optionally potassium hydroxide or potassium carbonate, and reacting the mixture under suitable cond

Abstract: The invention relates to a process for preparing potassium thiosulfate, potassium sulfite or potassium bisulfite comprising the following steps: Step (1a): providing a potassium hydroxide or potassium carbonate solution for neutralizing acid forming components such as dissolving SO2 or H2S; Step (1b): providing an SO2 contacting solution, containing at least some potassium sulfite or potassium bisulfite or potassium thiosulfate; Step (2): providing SO2 gas; Step (3): reacting these to absorb the SO2 gas and to form an intermediate reaction mixture comprising potassium sulfite, or potassium bisulfite or a mixture thereof, and optionally recovering the potassium sulfite, or potassium bisulfite or a mixture thereof, and/or optionally using steps 4 and 5; Step (4): adding sulfur or sulfide containing compound containing sulfur having the oxidation state of 0, ?2 or of between 0 and ?2 to the reaction mixture and optionally potassium hydroxide or potassium carbonate, and reacting the mixture under suitable conditi

Abstract: The invention relates to a process for preparing potassium thiosulfate, potassium sulfite or potassium bisulfite comprising the following steps: Step (1a): providing a potassium hydroxide or potassium carbonate solution for neutralizing acid forming components such as dissolving SO2 or H2S; Step (1b): providing an SO2 contacting solution, containing at least some potassium sulfite or potassium bisulfite or potassium thiosulfate; Step (2): providing SO2 gas; Step (3): reacting these to absorb the SO2 gas and to form an intermediate reaction mixture comprising potassium sulfite, or potassium bisulfite or a mixture thereof, and optionally recovering the potassium sulfite, or potassium bisulfite or a mixture thereof, and/or optionally using steps 4 and 5; Step (4): adding sulfur or sulfide containing compound containing sulfur having the oxidation state of 0, ?2 or of between 0 and ?2 to the reaction mixture and optionally potassium hydroxide or potassium carbonate, and reacting the mixture under suitable cond

Abstract: An efficient process for preparation of potassium thiosulfate (K2S2O3) is described. Potassium hydroxide (KOH) and elemental sulfur (S) are converted to potassium polysulfide, which is subsequently oxidized. The process allows using specifically designed process conditions such as mole ratios of potassium hydroxide to sulfur, and temperature, to obtain an optimized formulation of desired polysulfide, and a specifically designed set of conditions such as temperature, pressure, rate and duration of the oxidant during the oxidation conditions, to obtain a relatively high concentration of soluble potassium thiosulfate product with high purity, with relatively low amounts of byproducts. The manufacturing process can either be a batch process or a continuous process utilizing Continuous Stirred Tank Reactors (CSTR). The CSTR process is dependent on several design parameters, including pressure, and temperature optimization to avoid product instability.

Abstract: An efficient process for preparation of potassium thiosulfate (K2S2O3) is described. Potassium hydroxide (KOH) and elemental sulfur (S) are converted to potassium polysulfide, which is subsequently oxidized. The process allows using specifically designed process conditions such as mole ratios of potassium hydroxide to sulfur, and temperature, to obtain an optimized formulation of desired polysulfide, and a specifically designed set of conditions such as temperature, pressure, rate and duration of the oxidant during the oxidation conditions, to obtain a relatively high concentration of soluble potassium thiosulfate product with high purity, with relatively low amounts of byproducts. The manufacturing process can either be a batch process or a continuous process utilizing Continuous Stirred Tank Reactors (CSTR). The CSTR process is dependent on several design parameters, including pressure, and temperature optimization to avoid product instability.

Abstract: The invention relates to a process for preparing potassium thiosulfate, potassium sulfite or potassium bisulfite comprising the following steps: Step (1a): providing a potassium hydroxide or potassium carbonate solution for neutralizing acid forming components such as dissolving SO2 or H2S; Step (1b): providing an SO2 contacting solution, containing at least some potassium sulfite or potassium bisulfite or potassium thiosulfate; Step (2): providing SO2 gas; Step (3): reacting these to absorb the SO2 gas and to form an intermediate reaction mixture comprising potassium sulfite, or potassium bisulfite or a mixture thereof, and optionally recovering the potassium sulfite, or potassium bisulfite or a mixture thereof, and/or optionally using steps 4 and 5; Step (4): adding sulfur or sulfide containing compound containing sulfur having the oxidation state of 0, ?2 or of between 0 and ?2 to the reaction mixture and optionally potassium hydroxide or potassium carbonate, and reacting the mixture under suitable cond

Abstract: An efficient process for the continuous preparation of calcium thiosulfate (CaS2O3) from lime sulfur, through oxidation is described. The process involves oxidizing calcium polysulfide intermediate in a series of reactors to produce calcium thiosulfate as a clear liquid in high concentration with minimal byproducts. The process results in the complete destruction of polythionates, permitting the calcium thiosulfate produced to be useful in certain leaching processes for precious metals. The invention further makes it possible to recycle the process water from the leaching process for use as a raw material reactant in the process for calcium thiosulfate production.

Abstract: An efficient process for the continuous preparation of calcium thiosulfate (CaS2O3) from lime sulfur, through oxidation is described. The process involves oxidizing calcium polysulfide intermediate in a series of reactors to produce calcium thiosulfate as a clear liquid in high concentration with minimal byproducts. The process results in the complete destruction of polythionates, permitting the calcium thiosulfate produced to be useful in certain leaching processes for precious metals. The invention further makes it possible to recycle the process water from the leaching process for use as a raw material reactant in the process for calcium thiosulfate production.

Abstract: An efficient batch or semi-continuous method of production of relative high concentration, low byproduct-containing, calcium thiosulfate (CaS2O3) from lime, sulfur or calcium polysulfide, and sulfur dioxide under elevated reaction temperature conditions is described. The product is an emulsion of liquid calcium thiosulfate and solid byproducts. Under the conditions of the art, including the mole ratios of lime to sulfur, the temperature of the reaction process and the sulfur dioxide reaction conditions, including rate and duration, the byproducts are reduced to about 2% by weight.

Abstract: An efficient batch or semi-continuous method of production of relative high concentration, low byproduct-containing, calcium thiosulfate (CaS2O3) from lime, sulfur or calcium polysulfide, and sulfur dioxide under elevated reaction temperature conditions is described. The product is an emulsion of liquid calcium thiosulfate and solid byproducts. Under the conditions of the art, including the mole ratios of lime to sulfur, the temperature of the reaction process and the sulfur dioxide reaction conditions, including rate and duration, the byproducts are reduced to about 2% by weight.

Abstract: An efficient semi-continuous preparation of manganese thiosulfate (MnS2O3, MnTS) from manganese hydrosulfite and sulfur at elevated temperature is described. Manganese hydrosulfite is prepared from commercial manganese carbonate and sulfur dioxide. The resulting product is an emulation of liquid manganese thiosulfate and solid by-products. A manganese thiosulfate solution is produced according to the invention by use of certain mole ratios of MgCO3 to sulfur, and certain parameters such as the temperature of the reaction process and the pH conditions, including rate and duration of SO2 purging, which causes the by-products to be reduced to less than 2% by weight. The resulting manganese thiosulfate is a pinkish liquid with concentration up to 20%.

Abstract: Use of urease-inhibiting amounts of calcium polysulfide, potassium polysulfide, calcium thiosulfate, magnesium thiosulfate, and blends thereof, in combination with urea-containing fertilizer to significantly reduce potential losses of nitrogen due to ammonia volatilization.

Abstract: An efficient process to produce calcium thiosulfate (CaS2O3) from lime, sulfur and oxygen is described. By selecting appropriate process conditions such as mole ratios of lime to sulfur, temperature and pressure of the reaction process and the oxidation conditions, including rate and duration, the concentration of byproducts in the resulting suspension can be reduced to about 2% by weight or less. The solid particulate dispersion in the suspension tends to form a slimy solid suspension that is hard to filter if not treated properly. The suspension then can be acidified and treated with a flocculent. This agglomerates the solids into a floc that filters with ease. The resulting calcium thiosulfate is a clear liquid with concentrations achievable up to 29%.

Abstract: An efficient process for the preparation of magnesium thiosulfate involves reaction of magnesium hydrosulfite and sulfur at elevated temperature. Magnesium hydrosulfite can be prepared from commercial magnesium oxide and sulfur. Sulfur dioxide can be used to maintain pH. The resulting product is an emulsion of liquid magnesium thiosulfate and solid byproducts. Under controlled conditions, including mole ratios of MgO to sulfur, temperature of the reaction process, and pH, as well as rate and duration of SO2 purging, production of byproducts can be reduced to less than about 2% by weight. The magnesium thiosulfate solution can be prepared with concentrations of at least about 25%, preferably at least about 30%.

Abstract: An efficient process to produce calcium thiosulfate (CaS2O3) from lime, sulfur and oxygen is described. By selecting appropriate process conditions such as mole ratios of lime to sulfur, temperature and pressure of the reaction process and the oxidation conditions, including rate and duration, the concentration of byproducts in the resulting suspension can be reduced to about 2% by weight or less. The solid particulate dispersion in the suspension tends to form a slimy solid suspension that is hard to filter if not treated properly. The suspension then can be acidified and treated with a flocculent. This agglomerates the solids into a floc that filters with ease. The resulting calcium thiosulfate is a clear liquid with concentrations achievable up to 29%.