自廢棄活性碳觸媒回收貴重金屬鈀之研究

A Study on the Separation and Recovery of Palladium from Spent Pd/Active Carbon Catalyst

郭子瑋(Zi-Wei Guo)

指導教授 ： 蔡德華

國立臺北科技大學/工程學院/化學工程研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00031

摘要

本研究以廢棄觸媒做為實驗對象，將其中貴重金屬-鈀分離及回收，最後再從實驗結果，探討出較環保的回收製程，本實驗大致分為兩部分；第一部分為浸出實驗，此乃探討利用不同的酸類，在不同的溫度、固液比、時間，以及將觸媒先以高溫煅燒後將碳去除，在以予浸出。在這些條件中實驗出鈀的最適當浸出條件；第二部分為回收實驗，在此實驗中，將第一部分所浸出的氯化鈀溶液做為回收對象，利用甲酸做為還原劑，在不同溫度、pH、甲酸與氯化鈀溶液比例，以實驗結果探討出最佳的回收條件。
浸出率在觸媒800℃煅燒兩小時，以90℃、液固比20：1、反應時間2小時，用王水浸出可達鈀浸出率99%以上。而回收程序隨著pH增高反應速率隨之變快，在90℃、pH為8.31時，甲酸與含鈀離子溶液體積比為0.0067時，回收率即可達 99%以上，而鈀粉純度為98.5%以上。
由實驗結果得知，活性碳觸媒的表面積極大，每克觸媒約有1000m2，而附著在活性碳上的鈀，其每克觸媒表面積為100m2 ，使得溶解過程溫度對溶解效率影響甚小。而溫度與pH值對回收鈀粉的影響甚大，在較高的pH、溫度下，不僅能提高回收率及反應速率，更能大幅減少甲酸用量。

關鍵字

活性碳 ； 鈀 ； 回收 ； 甲酸 ； 氧化還原 ； 活性碳觸媒

並列摘要

In this study, We used spent active carbon catalyst to separate and recover for precious metals-palladium, finally, From the experimental results and provided a more environmentally friendly recycling process. The experiment was divided into two parts; The first part is leaching process, In this part, we experimented with different acids at different temperature, S/L ratio, Time. In these experimental conditions and find the optimal leaching conditions for palladium; The second part is recovery process, In this experiment, The recovery object is the first part experiment of leaching solution of Palladium chloride solution, we used of formic acid as reducing agent and experimented with different temperature, pH, formic acid/Palladium chloride solution ratio(F/P ratio), And we will be used experimental results to find the optimal recycle conditions. 1111111 11111111111

The effect of leaching rate at 90℃, S/L ratio 20:1, reaction time 2 hours, the palladium dissolution ratio can be more than 99%. The recovery process efficiency increases with increasing pH, along with faster reaction rate, At 90 ℃, pH value of 8.310 and F/P ratio is 0.0067, the effect of recovery ratio can be more than 99%, with 98.5% purity was chieve. 111111111111111111111111

The results indicate that, the surface area of active carbon catalyst about per gram of catalyst of about 1000 m2, and cohered to the active carbon on palladium, the surface area per gram of 100 m2, making the process of dissolution and even temperature on the dissolution efficiency of small. The temperature and pH value on the recovery of palladium powder has great impact, at higher pH and temperature, not only can increase the recovery efficiency and reaction rate, more significantly reduce the amount of formic acid. 1

並列關鍵字

Recovery ； Spent Catalyst ； Active Carbon ； Palladium ； Redox reaction ； Active Carbon Catalyst (A.C.C.)

參考文獻

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