The mass spectrometric behavior of three depsidones isolated from Lichen was studied by elec-trospray tandem mass spectrometry,showing that these compounds in ESI-MSn could produce many daugh-ter ions.

A novel energy saving and exhaust reduction process,characterized by phosphoric acid concentration with the heat recovered from the DAP tail gas exhausted from the pre-neutralization reactor,is proposed for AP production,which results in the energy consumption reduced by 31.

For problems occurred during the production after upgrade of the tube and shell type graphite heat exchanger and axial flow pump equipment of the phosphoric acid concentration system for DAP production,a revamp scheme for parallel use of a new train and an old train of graphite heat exchanger and axial flow pump with different type and size is adopted.

The concentration of waste sulfuric acid increased from 20% to 37% by using steam heat in a equipment and 80% H_2SO_4 which would be used to decompound ilmenite was obtained by mixing with 98% H_2SO_4.

Study on technology for production of IMAP with concentrated phosphoric acid;