Study On The Occurrence Status Of Associated Sulfur In Guizhou Phosphate Mines And The Application Of Fluorine And Silicon Resource

Guizhou Province is rich in phosphate rock resources,and the large-scale processing process of phosphate rock has brought a large number of valuable associated elements to large-scale production.The comprehensive utilization of phosphate rock associated resources is the key to promoting the transformation and upgrading of the phosphate rock industry,which is of great significance to the development of the phosphate chemical industry in Guizhou Province.This paper mainly studies the occurrence state of associated sulfur in Guizhou phosphate mines and the application of associated fluorosilicon resources.The specific research content and achievements are as follows:（1）Samples collected from phosphate ores in Wengfu,Kaiyang,and Zhijin regions of Guizhou Province were examined by X-ray photoelectron spectroscopy（XPS）,X-ray diffraction（XRD）,inductively coupled plasma mass spectrometry（ICP-MS）,scanning electron microscopy（SEM）,and temperature programmed oxidation infrared carbon sulfur analysis（TPO-IR）.The research results show that the content of sulfur in phosphate rock is not high,and there is a local enrichment phenomenon.The total sulfur content of the three phosphate rock areas is 2.14%（Kaiyang phosphate rock）,1.18%（Zhijin phosphate rock）,and 1.06%（Wengfu phosphate rock）,respectively.Kaiyang phosphate rock and Wengfu phosphate rock both have the same type of Fe S,with their content of 0.922%and0.064%,respectively.There are relatively complex sulfate types in the three phosphate rock areas,including Mg SO₄ and Ca SO₄.The Wengfu phosphate rock and Kaiyang phosphate rock are mainly Ca SO₄,with a content of 0.562%and 0.482%,respectively,while the Zhijin phosphate rock is mainly Mg SO₄,with a content of 0.610%.（2）Silicon nanowires were prepared by chemical vapor deposition using Si F₄,a by-product of phosphorus chemical industry,as a silicon source and Al₂O₃ as a catalyst.The reaction products were detected by SEM,TEM,and EDS.The results show that the reaction system can successfully prepare silicon nanowires under certain conditions.After the reaction,there are obvious etching traces on the surface of the silicon substrate,and there is no complete adhesion between the silicon nanowire film and the silicon wafer substrate,indicating that the Si of the silicon nanowire comes from Si F₄.When using a single crystal silicon wafer as the substrate,the Si F₄ flow rate is 250 sccm,the reaction time is 30 min,and the reaction temperature is 1000 ^oC,the silicon nanowires have a higher yield;Under the same conditions,when silicon particles are used as the substrate,the growth potential of silicon nanowires is optimal at a reaction temperature of 995 ^oC.（3）The ion doped modified Ti O₂ photocatalyst is prepared using Si F₄,a by-product of phosphorus chemical industry,in which Si forms Si O₂ as a carrier for the catalyst,and F is used as a non-metallic doping to modify the Ti O₂ photocatalyst.At the same time,metal（such as Fe,Zn,Co,Ce）ions are used to conduct single or double doping on the catalyst to further modify the Ti O₂ photocatalyst.The results show that the catalyst sample prepared by Si F4 has a spherical or hollow spherical structure composed of small particles,with a diameter of about 1.5～2μm.Ti O₂ is mainly rutile phase,and local diffraction shows that the grain size of the sample is about 20～80 nm.It may be due to the variety of doped ions,resulting in complex crystal surface structure and complex crystal composition.When using Ti CN as a Ti source,the photocatalyst doped with 1%Co and 1%Ce has the best photocatalytic activity in the actual experiment of photocatalytic degradation of organic compounds.2-4,D can be completely degraded;Under the same conditions,using Ti N as the Ti source,1%Zn and 1%Ce bimetallic doped Ti O₂ photocatalysts can also completely degrade 2-4,D.In summary,this study has achieved good results in the occurrence of associated sulfur in phosphate rock and the application and development of fluorine and silicon resources,providing theoretical reference for improving the comprehensive utilization efficiency of phosphate rock resources in the future,while also improving the environmental pollution caused by the discharge of associated minerals from phosphate rock.