山核桃外蒲壳制备碳酸钾工艺优化

Preparation Technology Optimization of Potassium Carbonate from Hickory Hull

原子吸收分光光度法（AAS）分析得知：山核桃外蒲壳的无机成分中含有较高的钾元素,湿消化法和干消化法处理壳粉所得的结果基本一致。以山核桃外蒲壳为原料,采用热处理法制取碳酸钾,对灰化温度、灰化时间、材料粒度3个因素进行了正交试验,分别以灰化率、钾得率和碳酸钾含量为考察指标,并通过热值分析和X射线衍射（XRD）分析,确定了最佳工艺条件。试验结果表明：灰化温度600℃,灰化时间6 h,材料粒度5-10 mm,钾得率约30%;进一步的煅烧条件正交试验表明：纯化后的粗碱煅烧温度600℃,煅烧时间0.5 h,制备的碳酸钾产品纯度高达98%。

Hickory Hull is a kind of forestry waste and severely pollutes ecological environment, so how to make use of forest resources is the aim of thisresearch. The inorganic composition of Hickory Hull was analyzed by the atomic absorption spectrometry. The results showed that there were more K elements in Hickory Hull. It is nearly common that wet digestive method compared with dried digestive. The thermal treatment was studied on Hickory Hull to produce potassium carbonate, and orthogonalization test was projected on three elements, ashing temperature, time and material diameter. The best technology condition was determined by the experiment index of ash and K rate, the contents of potassium carbonate, through thermal analysis and X ray diffraction analysis. The results showed that the optimal conditions of ashing temperature 6000C, ashing time 6 h, material diameter 5 - 10 ram, the rate of K was about 30% ; calcination temperature 600℃, calcination time about 0.5 hours, the purity of potassium carbonate can be up to 98 %.