公开(公告)号：US4678649A

公开(公告)日：1987-07-07

申请号：US872061

申请日：1986-06-06

Applicant: Iosef Alexander ,  Menachem Bar-on

Inventor： Iosef Alexander ,  Menachem Bar-on

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

CPC classification number: C01B25/301 ,  C01B25/303

Abstract: The present invention relates to a process for the manufacture of monopotassium phosphate of a high purity without utilizing organic solvents. According to the process, monopotassium sulfate is reacted, at a temperature in the range of between 40 to 100 degrees 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 elininated, with the calcium sulfate resulted thereto. After separating out the calcium sulfate, the filtrate is neutralized to a pH in the range of between 3 to 7, with a calcium-containing compound comprising Ca(OH).sub.2, CaO or CaCO.sub.3, or mixtures thereof. From the filtrate obtained, pure monopotassium phosphate is crystallized out. The process is characterized by a high recovery of the P.sub.2 O.sub.5 and K.sub.2 O values, the monopotassium phosphate produced being completely free of chloride ion.

Abstract translation: 本发明涉及不使用有机溶剂制备高纯度磷酸二氢钾的方法。 根据该方法，在磷酸存在下，硫酸氢钾在40至100度的温度下与选自磷酸盐岩，磷酸二钙或其混合物的磷酸盐成分反应。 存在于起始磷酸盐岩中的普通金属杂质，有机物和氟化物基本上被酸化，产生硫酸钙。 在分离出硫酸钙之后，将滤液用包含Ca（OH）2，CaO或CaCO 3的含钙化合物或其混合物中和至3至7范围内的pH。 从得到的滤液中，将纯的磷酸二氢钾结晶出来。 该方法的特征在于P2O5和K2O值的高回收率，所产生的磷酸二氢钾完全不含氯离子。