【摘要】：電解錳陽極泥因其組成成分復雜,化學活性低,長久以來難以直接回收利用。玉米稈可作為一種成本低廉,來源廣泛的有機還原劑,通過還原浸出電解錳陽極泥來制備化學二氧化錳,實現(xiàn)廢棄資源的二次回收和再利用。本文系統(tǒng)研究了整個制備工藝過程的各個環(huán)節(jié),探索了各階段相關工藝參數(shù)對最終產(chǎn)品化學二氧化錳質(zhì)量的影響。結(jié)合有關理論分析,研究各環(huán)節(jié)工藝發(fā)展方向,并通過試驗驗證,得到用玉米稈還原浸出電解錳陽極泥制備化學二氧化錳的最佳工藝參數(shù)。對比用貧菱錳礦合成制備的化學二氧化錳產(chǎn)品,了解兩種方法生產(chǎn)的最終CMD產(chǎn)品性能差異。碳酸錳熱解法是一種常用的制備化學二氧化錳工藝方法。其過程可分為四個階段,分別是硫酸錳溶液的制備、碳化結(jié)晶、初級二氧化錳制備和產(chǎn)品精制。硫酸錳溶液的制備包括玉米稈還原浸出和浸出液除雜兩個階段,其分別決定了電解錳陽極泥的回收利用率和最終產(chǎn)品的純度。碳化結(jié)晶部分的各種工藝條件對碳酸錳視密度的影響明顯,進而影響最終的化學二氧化錳視密度,但對產(chǎn)品的電活性影響較小。合理安排碳酸氫銨用量、給藥方式、結(jié)晶溫度和時間可獲得視密度為2.1g/cm3的碳酸錳產(chǎn)品。初級二氧化錳制備部分,時間和溫度決定了熱解效率和產(chǎn)物晶型,結(jié)果表明,在380℃下熱解6h后所得產(chǎn)物Mn02含量為68.96%以γ-MnO2為主,電化學活性最高。產(chǎn)品精制部分,對初級二氧化錳酸處理和氧化后能進一步提純并可改善顆粒形貌,提高視密度。本研究在綜合考慮了生產(chǎn)條件、經(jīng)濟成本等現(xiàn)實情況下,選擇各階段的最佳工藝參數(shù)進行試驗,最終獲得MnO2含量達91.29%,視密度為1.83g/cm3,電容量為251.6mAh的化學二氧化錳產(chǎn)品。用貧菱錳礦制備的化學二氧化錳產(chǎn)品,其MnO2含量達91%,視密度為1.90g/cm3,電容量為249.43mAh。由此可見,兩者在視密度及電活性方面效果大致相同,均可達到優(yōu)質(zhì)化學二氧化錳的水平。
[Abstract]:Electrolytic manganese anode mud is difficult to be directly recovered for a long time because of its complex composition and low chemical activity. Cornstalk can be used as an organic reductant with low cost and wide source. Chemical manganese dioxide can be prepared by reducing and leaching electrolytic manganese anode mud to realize the secondary recovery and reuse of waste resources. In this paper, every link of the whole preparation process is systematically studied, and the influence of the relevant process parameters on the quality of the final product chemical manganese dioxide is explored. Based on the theoretical analysis, the development direction of each process was studied, and the optimum technological parameters for the preparation of chemical manganese dioxide from electrolytic manganese anode slime by cornstalk reduction leaching were obtained. Compared with the chemical manganese dioxide products synthesized from low rhodochromatic manganese ore, the difference of the properties of the final CMD products produced by the two methods was understood. Pyrolysis of manganese carbonate is a common process for preparing chemical manganese dioxide. The process can be divided into four stages: preparation of manganese sulfate solution, carbonation crystallization, preparation of primary manganese dioxide and purification of product. The preparation of manganese sulfate solution includes two stages of cornstalk reduction leaching and leaching solution impurity removal which determine the recovery efficiency of electrolytic manganese anode mud and the purity of the final product respectively. The effect of various processing conditions on the apparent density of manganese carbonate is obvious, and then the final apparent density of manganese dioxide is affected, but the effect on the electrical activity of the product is small. Manganese bicarbonate with apparent density of 2.1g/cm3 can be obtained by reasonably arranging the amount of ammonium bicarbonate, the way of administration, the crystallization temperature and time. In the preparation of primary manganese dioxide, the pyrolysis efficiency and crystal form of the product are determined by time and temperature. The results show that the Mn02 content of the product is 68.96% after pyrolysis at 380 鈩，

本文編號：2153208