公开(公告)号：US5445804A

公开(公告)日：1995-08-29

申请号：US184593

申请日：1994-01-21

申请人： Alexander Iosef

发明人： Alexander Iosef

IPC分类号： C01B33/12 ,  C01B33/193

CPC分类号： C01B33/193 ,  C01P2002/02 ,  C01P2006/11 ,  C01P2006/12 ,  C01P2006/80 ,  C01P2006/82

摘要： A process for the manufacture of pure amorphous silica from rocks containing non-crystalline silica is described. The process comprises the steps of: (a) dissolution of said rock in an alkaline solution comprising sodium hydroxide and sodium carbonate, obtaining a solution of sodium silicate; (b) precipitation of pure amorphous silica by adding sodium bicarbonate into said sodium silicate and co-producing sodium carbonate, the weight ratio between SiO.sub.2 and Na.sub.2 O in said dissolution step is in the range of between 0.5 to 3.0; and (c) the sodium carbonate solution is transformed into crystalline sodium bicarbonate, by a salting out reaction with sodium chloride, being recycled to the process. According to a preferred embodiment, the alkaline solution is obtained by the caustification of sodium carbonate with calcium hydroxide. The preferred concentration of sodium hydroxide in said dissolution step is in the range of 4% to 14% by weight.

摘要翻译： 描述了从含有非结晶二氧化硅的岩石制造纯无定形二氧化硅的方法。 该方法包括以下步骤：（a）将所述岩石溶解在包含氢氧化钠和碳酸钠的碱性溶液中，得到硅酸钠溶液; （b）通过向所述硅酸钠中加入碳酸氢钠并共同生产碳酸钠沉淀纯无定形二氧化硅，所述溶解步骤中SiO 2与Na 2 O的重量比在0.5至3.0的范围内; 和（c）通过与氯化钠的盐析反应将碳酸钠溶液转化成结晶碳酸氢钠，再循环到该方法中。 根据优选的实施方案，碱性溶液是通过用氢氧化钙对碳酸钠进行除碱而获得的。 所述溶解步骤中优选的氢氧化钠浓度在4重量％至14重量％的范围内。

公开(公告)号：US4759920A

公开(公告)日：1988-07-26

申请号：US872062

申请日：1986-06-06

申请人： Alexander Iosef ,  Menachem Bar-On

发明人： Alexander Iosef ,  Menachem Bar-On

IPC分类号： C01B25/30 ,  C01B15/16 ,  C01B25/26

CPC分类号： C01B25/303

摘要： The present invention relates to a process for the manufacture of disodium phosphate of a high purity without utilizing organic solvents. According to the process, monosodium sulfate is reacted, at a temperature, in the range of 40 to 100 degrees C. with a phosphate constituent selected from phosphate rock, dicalcium phosphate or mixtures thereof, in the presence of phosphoric acid. The common metal impurities, organic matter and fluorides present in the starting phosphate rock are substantially complete eliminated with the solid gypsum or dicalcium phosphate resulted thereto. After separating said solid, the filtrate is treated in two neutralization stages: first by a calcium constituent selected from calcium carbonate, calcium hydroxide or mixtures thereof and separating the formed dicalcium phosphate, followed by a second neutralization with an alkali sodium constituent selected from sodium hydroxide, sodium carbonate and sodium bicarbonate or mixtures thereof at a pH in the range of 8.0 to 9.5. From the resulted filtrate, pure disodium phosphate is obtained by crystallization. The process is characterized by a high recovering of the P.sub.2 O.sub.5 and Na.sub.2 O values, the resulted product being substantially free of chloride ion.

公开(公告)号：US4585636A

公开(公告)日：1986-04-29

申请号：US661710

申请日：1984-10-17

申请人： Alexander Iosef ,  Menachem Bar-on ,  Jacob Oren ,  Dagobert Kellerman

发明人： Alexander Iosef ,  Menachem Bar-on ,  Jacob Oren ,  Dagobert Kellerman

IPC分类号： C01B25/234 ,  C01B25/46 ,  C01B25/16

CPC分类号： C01B25/461 ,  C01B25/234 ,  C01B25/462

摘要： The present invention relates to an improved process for the manufacture of purified phosphoric acid from phosphate rock. According to the invention, phosphate rock is decomposed by a mineral acid selected from hydrochloric acid, sulfuric acid or mixtures thereof. The dissolution liquor obtained is reacted with a calcium-containing compound such as calcium oxide, calcium carbonate, tricalcium phosphate and fines of phosphate rock producing an aqueous solution containing monocalcium phosphate in an amount corresponding to between 0.4% to 5.5% by wt CaO. After the separation of the precipitated solids, the clarified solution is extracted by an organic solvent having the property to extract the phosphate component. The phosphoric acid is subsequently recovered from the solvent extract by known methods such as washing or distillation.

摘要翻译： 本发明涉及从磷酸盐岩制造纯化磷酸的改进方法。 根据本发明，磷酸盐岩由选自盐酸，硫酸或其混合物的无机酸分解。 将得到的溶解液与含钙化合物如氧化钙，碳酸钙，磷酸三钙和磷酸盐岩的细粉反应，生成含有相当于0.4〜5.5重量％CaO的磷酸一钙的水溶液。 析出的固体分离后，通过具有提取磷酸盐成分性质的有机溶剂提取澄清溶液。 随后通过已知的方法例如洗涤或蒸馏从溶剂提取物中回收磷酸。