我国低阶煤储量大,低阶煤材料化利用是当前国家重大需求。另外,我国城市污泥排放量逐年增加,高含水率污泥资源化利用至关重要。低阶煤和污泥水热碳化可有效资源化利用原料内的硫氮元素,制备硫氮掺杂水热炭。水热炭孔隙较不丰富,对其进行活化造孔可丰富其孔隙结构,制备得到硫氮掺杂多孔炭。选用较为温和K2CO3作为活化剂,探究K2CO3活化不同次烟煤与污泥水热炭制备多孔炭材料的性质,并研究多孔炭对CO2和SO2的吸附性能。结果表明,次烟煤和污泥水热炭经K2CO3活化改性后,硫氮元素含量相较于原来的水热炭均有所减少,多孔炭的比表面积由原水热炭的23.92m2/g增至331.77m2/g,孔体积由原水热炭的0.07cm3/g增至0.23cm3/g。制备的多孔炭对CO2和SO2具有一定的吸附效果,次烟煤与污泥质量比为7∶3,水热碳化温度为160℃时,经700℃K2CO3活化所制备的多孔炭在25℃下,对CO2吸附量为1.56mmol/g;次烟煤与污泥质量比为1∶1,水热碳化温度为160℃时,所制备的水热炭经活化后,其在吸附温度为120℃时,对SO2的吸附量为52.2mg/g,且随着水热碳化温度升高,其吸附量有所下降,共水热炭相比于单一水热炭对CO2和SO2的吸附性能更好。研究结果可为低阶煤和污泥清洁高效利用和低成本CO2、SO2吸附剂开发提供理论依据。

With the discharge of urban sewage sludge is rising, and the demand for resource utilization of high moisture sewage sludge is crucial. Hydrothermal carbonization of low-rank coal and sewage sludge can utilize the sulfur and nitrogen elements in raw materials effectively andprepare sulfur and nitrogen doped hydrochar. Hydrochar had relatively less abundant pores, and activation by activator can enrich its porestructure and prepare sulfur nitrogen co-doped porous carbon. In this paper, relatively mild K CO was chosen as an activator for porous carbon preparation from co-hydrochars of sub-bituminous coal and sewage sludge, and the adsorption performance of porous carbon onCO and SOwas also studied. The results showed that compared with those of the original hydrochars, the sulfur and nitrogen contents reduced after the activation modification by KCO, and the specific surface area of the porous carbon was increased from 23.92 m / g to331.77 m / g, and the pore volume was increased from 0.07 cm / g to 0.23 cm / g. The prepared porous carbon had certain adsorptioneffect on CO and SO. For the hydrochar obtained from co-hydrothermal carbonizaiton at the condition that the mass ratio of sub-bituminous coal to sewage sludge was 7 ∶ 3, and the hydrothermal carbonization temperature was 160 ℃ , activated by KCOat 700 ℃ , the porous carbon has a CO adsorption capacity of 1.56 mmol/ g at 25 ℃ ; when the mass ratio of sub-bituminous coal to sewage sludge was 1 ∶ 1and the hydrothermal carbonization temperature was 160 ℃ , the activated hydrochar prepared had an adsorption capacity of 52.2 mg/ gfor SO at an adsorption temperature of 120 ℃ . The adsorption amount decreased with the increase of the hydrothermal carbonization temperature, and the adsorption performance of the porous carbon from co-hydrochar was better than that from the separate hydrochar for COand SO. The results may provide a theoretical basis for the clean and efficient utilization of low-rank coal and sewage sludge, as well asfor the preparation of low-cost and efficient CO and SO adsorbent.

0 引言

1 试验

   1.1 试验原料

   1.2 水热炭样品的制备

   1.3 水热炭活化改性方法

   1.4 活化后水热炭的表征

   1.5 CO2吸附性能测试

2 结果与讨论

   2.1 K2CO3活化改性后的水热炭的性质

   2.2 活化改性后水热炭对CO2及SO2吸附性能

3 结论