摘 要本文比较研究了不同温度、不同质量浓度下牛粪、蚓粪及其生物炭对重金属离子的吸附差异,并对相同条件下的牛粪、蚓粪生物炭对重金属的吸附行为进行了热力学参数计算。结果表明,温度相同时,牛粪、蚓粪及其生物炭对重金属的吸附率随着质量浓度的升高而增高,但当增大到一定程度即不再变化。相同质量浓度时,牛粪、蚓粪及其生物炭对重金属的吸附量与吸附剂种类有关,整体呈现先上升后下降的趋势。根据热力学计算知道,不同温度下牛粪、蚓粪生物炭对重金属的吸附过程是放热反应,低温有利于吸附,温度过高吸附能力反而下降。总体来说,牛粪或蚓粪生物炭的吸附能力与离子种类有关,吸附效率由高到低表现为Cu2+、Zn2+、Pb2+、Cd2+。 90030
Abstract:This research compared the difference in adsorption Cu2+, Zn2+, Pb2+, Cd2+ ions on cow dung, vermicompost and their derived biochar under different temperatures and adsorbent dosage, besides, thermodynamic parameters were calculated for Cu2+, Zn2+, Pb2+, Cd2+ ions adsorption onto cow dung, vermicompost and their derived biochar under the same conditions。。 The results showed that the adsorption rate of Cu2+, Zn2+, Pb2+, Cd2+ ions increased with the increase of adsorbent dosage at the same temperature, but it was no longer changed when the concentration increased to a certain extent。 With the same dosage, the adsorption capacity showed first increase and then decrease for Cu2+, Zn2+, Pb2+, Cd2+ ions adorption onto cow dung, vermicompost and biochar。 According to the thermodynamic calculation, it is known that the adsorption process of Cu2+, Zn2+, Pb2+, Cd2+ ions is an exothermic reaction at different temperatures, and the low temperature is favorable for the adsorption, and the adsorption capacity may decrease when temperature is too high。 On the whole, the adsorption capacity of Cu2+, Zn2+, Pb2+, Cd2+ onto cow dung, vermicompost and their derived biochar was related to the species of heavy metal ions, and the order of removal efficiency was Cu2+> Zn2+>Pb2+> Cd2+。
毕业论文关键词: 牛粪; 蚓粪; 吸附; 生物炭; 重金属
Keyword: Cow dung; Vermicompost; Adsorption; biochar; Heavy metal
目 录
引言 4
1 材料和方法 4
1。1供试材料 4
1。2研究方法 4
1。3 计算方法 5
1。4 吸附热力学计算 5
2 结果与分析 5
2。1 不同质量浓度下牛粪、蚓粪及其生物炭对Cu2+、Zn2+、Pb2+、Cd2+的吸附特性 5
2。1。1 对Cu2+的吸附特性 6
2。1。2 对Zn2+的吸附特性 6
2。1。3 对Pb2+的吸附特性 6
2。1。4 对Cd2+的吸附特性 7
2。2 不同温度下牛粪、蚓粪及其生物炭对 Cu2+、Zn2+、Pb2+、Cd2+的吸附特性 7
2。2。1 对Cu2+的吸附特性 7
2。2。2 对Zn2+的吸附特性 8
2。2。3 对Pb2+的吸附特性 8
2。2。4对Cd2+的吸附特性 9
2。3 不同温度下牛粪、蚓粪及其生物炭吸附 Cu2+、Zn2+、Pb2+、Cd2+的热力学计算 9
3。结论与讨论