二甲基亚砜工业废渣制备农用硝酸钾的研究

Study on preparation of agricultural potassium nitrate with industrial dimethyl sulphoxide waste residue

二甲基亚砜产品用途广泛,具有较好的经济效益,但是副产的固体废渣处理是行业内难题。研究了以二甲基亚砜工业废渣为原料,经氧化、合成、提纯等步骤制得农用硝酸钾产品的技术可行性。研究结果表明,采用臭氧可将废渣中的亚硝酸钠100%转化为硝酸钠,在浓缩蒸发水量为25%、冷却结晶温度为10℃、物料配比(硝酸钠与氯化钾的物质的量比)为1.2∶1的条件下与氯化钾反应可得硝酸钾粗产品,经过精制提纯后产品纯度可达98.3%,符合GB/T 20784—2013《农业用硝酸钾》要求,表明利用废渣生产农用硝酸钾是可行的,为二甲基亚砜工业废渣的利用找到了新思路。

Dimethyl sulphoxide(DMSO)is widely used and has good economic benefits,but the by-product of solid waste is a problem.The synthesis of agricultural potassium nitrate by using industrial dimethyl sulphoxide waste residue as raw material,through oxidation,purification and other steps,was studied.Results showed that the sodium nitrite residues could be converted into 100%sodium nitrate by the ozone.Crude potassium nitrate product could be obtained when the sodium nitrate reacted with potassium chloride under the conditions of 25%concentrated water evaporation,10℃cooling crystallization tempera-ture and 1.2∶1 materials mix ratio(amount of substance ratio of sodium nitrate to potassium chloride).After the purification,the product′s purity could reach 98.3%,which met the requirements of Agricultural Potassium Nitrate,GB/T 20784-2013.Therefore,it was indicated that the production of agricultural potassium nitrate with residue is feasible,and it has found a new way for the use of DMSO industrial waste.