本文選題：磷鉀伴生礦 + 三聚磷酸鋁��； 參考：《武漢工程大學》2015年碩士論文

【摘要】：我國可溶性鉀鹽資源缺乏且磷礦絕大部分屬于中低品味,致使農業(yè)施用化肥多氮少磷缺鉀現(xiàn)象嚴重。而以鉀長石(K2O·Al2O3·6SiO2)為代表的難溶性鉀資源卻分布廣泛、儲量極其豐富。湖北宜昌地區(qū)磷鉀伴生礦儲量豐富,其組成主要包括膠磷礦、鉀長石和石英等物質組成。合理開發(fā)、利用該地區(qū)磷鉀伴生礦資源,有利于緩解我國水溶性鉀資源的不足和提升磷資源綜合利用率。利用磷鉀伴生礦酸浸液生產化肥,除雜得到的粗氫氧化鋁若作為廢料丟棄是一種資源的浪費,且會對環(huán)境造成危害,對其回收利用,有利于提高磷鉀伴生礦綜合利用的經濟性。本文探索了一條回收利用酸浸液生產化肥除雜產生的粗氫氧化鋁,提純制備氫氧化鋁,合成防銹顏料三聚磷酸鋁的工藝線路。主要工作包括:磷鉀伴生礦酸浸液凈化得到粗氫氧化鋁、粗氫氧化鋁堿溶提純制備氫氧化鋁以及利用提純的氫氧化鋁與磷酸合成防銹顏料三聚磷酸鋁。并結合化學分析、X-射線衍射儀(XRD)以及傅里葉紅外光譜儀(FT-IR)對合成的產品進行了表征分析。主要結論如下:(1)利用磷鉀伴生礦酸浸液生產化肥,直接用氨水調節(jié)中和,溶液中雜質離子以及氟硅酸鹽與氨水反應,形成沉淀進入粗氫氧化鋁中,導致粗氫氧化鋁中氧化鋁與二氧化硅的質量比(A/S)較小、且酸浸液中含有大量的氯離子,不利于后續(xù)鋁元素的回收利用以及低氯氮磷鉀復合肥的制備,因此需要對酸浸液進行除氯和除硅的處理。本文采用添加硫酸蒸餾除氯的方法,磷鉀伴生礦反應后的酸浸液,加入計量后的硫酸在70℃、0.09 MPa(真空度)下蒸餾50 min,此時酸浸液體積剩余8%左右,經測定酸浸液中80%左右的氯離子被去除。除氯后的酸浸液,加入一定量的蒸餾水和雙氧水,采用氧化絮凝法除硅。結果表明經過除硅后,粗氫氧化鋁中Al2O3含量由17.68%提高至23.04%,SiO2含量由10.28%下降到4.63%,A/S由1.71提高至4.97。(2)研究了堿溶工藝條件對氧化鋁溶出率的影響,結果表明:粗氫氧化鋁與3mol/L氫氧化鈉按液固比5在90℃下反應40 min,氧化鋁的溶出率可達到72%。鋁酸鈉溶液利用CaO對進行脫硅處理,凈化后的鋁酸鈉溶液分別采用NaAlO2-HNO3法和制備的氫氧化鋁。研究結果表明,NaAlO2-HNO3法和鋁酸鈉溶液種分法制備氫氧化鋁純度均≥96%。(3)以制備的氫氧化鋁和分析純磷酸為原料,對影響合成防銹顏料三聚磷酸鋁的主要因素進行了研究,得到優(yōu)化條件為:原料(P2O5與Al2O3摩爾比)為3.0,中和反應時間為60 min,中和反應溫度為70℃,縮合反應溫度290℃,縮合反應時間為4 h。化學分析結果、FT-IR、XRD表明制備的產品是三聚磷酸鋁且主組分含量符合Q/HGY07-1999的要求。
[Abstract]:The lack of soluble potassium salt resources in China and the fact that most of the phosphate rocks belong to medium and low taste have caused a serious phenomenon of the agricultural application of chemical fertilizer with more nitrogen and less phosphorus and less potassium. The insoluble potassium resources, represented by K _ 2O Al2O3 _ 6SiO _ 2, are widely distributed and rich in reserves. Phosphorus and potassium associated deposits are abundant in Yichang area of Hubei Province, and their composition mainly includes mineral composition of colloid phosphate, potassium feldspar and quartz. Reasonable exploitation and utilization of phosphorus and potassium associated mineral resources in this area will help to alleviate the shortage of water-soluble potassium resources and improve the comprehensive utilization rate of phosphorus resources in China. It is a waste of resources to produce chemical fertilizer by acid leaching solution associated with phosphorus and potassium, and if the coarse aluminum hydroxide is discarded as waste material, it will cause harm to the environment, and the recovery and utilization of it will help to improve the economy of comprehensive utilization of phosphorus and potassium associated minerals. In this paper, a technological route of recovering crude aluminum hydroxide from chemical fertilizer and impurity removal, purifying and preparing aluminum hydroxide, and synthesizing antirust pigment aluminum triphosphate has been explored. The main work includes: purification of phosphorus-potassium acid-leaching solution to obtain coarse aluminum hydroxide, alkali purification of crude aluminum hydroxide to prepare aluminum hydroxide, and synthesis of antirust pigment aluminum triphosphate from purified aluminum hydroxide and phosphoric acid. The synthesized products were characterized and analyzed by chemical analysis X- ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FT-IR). The main conclusions are as follows: (1) the chemical fertilizer is produced from phosphorus-potassium acid-leaching solution, which is directly neutralized with ammonia water, and impurity ions in the solution and fluorosilicate react with ammonia to form precipitates into coarse aluminum hydroxide. As a result, the mass ratio of alumina to silica in crude aluminum hydroxide is smaller than A / S, and there is a large amount of chlorine ions in the acid extract, which is not conducive to the subsequent recovery of aluminum and the preparation of low chloro nitrogen, phosphorus and potassium compound fertilizer. Therefore, it is necessary to remove chlorine and silicon from acid leachate. In this paper, by adding sulfuric acid distillation to remove chlorine, the acid leachate of phosphorus and potassium associated with ore reaction is distilled for 50 min at 70 鈩，

本文編號：1803618