Activated carbon production: Recycling KOH to minimize waste

作者：Montes Vicente; Hill Josephine M^*

来源：Materials Letters, 2018, 220: 238-240.

DOI：10.1016/j.matlet.2018.03.019

• Activated carbon
• KOH
• Recycle
• Petroleum coke
• Carbon black

Synthesis of activated carbon by chemical activation results in materials with high surfaces areas and pore volumes (e.g., >1800 m(2)/g and >1 cm(3)/g). The main problems are the large amount of chemical required and the waste water created. To solve these problems, we have studied the recycle of KOH, focusing on the impacts of impurities originating in the starting materials and transferring to the solution used for washing the product. After activation of petroleum coke and carbon black, potassium was recovered in an aqueous solution including mainly KOH and K2CO3. The higher the fraction of the more active form of potassium (i.e., KOH), the higher the level of activation in subsequent experiments. The presence of sulphur increased the fraction of KOH recovered. Full recovery of potassium was achieved using HNO3 in the washing solution, but this acid also dissolved others species, such as Si and Al, that were detrimental for carbon activation.

• 出版日期2018-6-1