| abstract |
The invention relates to a method for preparing humic acid, and in particular relates to a method for preparing humic acid by using wheat straws. The method comprises the following steps: by taking the wheat straws as raw materials, firstly performing high temperature carbonization, then performing nitric acid activation, and finally performing alkaline solution extraction and sulfuric acid sedimentation to prepare humic acid. According to the method disclosed by the invention, the wheat straws are taken as the raw materials, and because China is a big agricultural country and wheat is a main crop, wide raw material sources and low cost can be achieved; and prepared agricultural humic acid can be reapplied to crops by virtue of biological organic fertilizer processing so as to achieve recycling utilization for resources. The extraction method for preparing humic acid, disclosed by the invention, is performed under room temperature conditions, and is mild in condition and simple and convenient to operate. |