生物炭的稳定性及其评价方法

围绕生物炭稳定性概念,论述了其影响因素,并对比分析生物炭稳定性的研究方法及预测模型。结果表明,生物炭稳定性的基础是其具有高度芳香化结构和土壤团聚体的保护作用,温度、原料及环境条件是影响生物炭稳定性的主要因素,生物炭稳定性最优评估方法为同位素标记法和双指数模型相结合,但其仍具有一定的局限性。在此基础上,指出不同土壤类型、轮作方式及预测模型是当前生物炭稳定性研究的前沿领域和深化方向。     

Effects and Economic Sustainability of Biochar Application on Corn Production in a Mediterranean Climate

The effects of two types of biochar on corn production in the Mediterranean climate during the growing season were analyzed. The two types of biochar were obtained from pyrolysis of Pinus pinaster. B1 was fully pyrolyzed with 55.90% organic carbon, and B2 was medium pyrolyzed with 23.50% organic carbon. B1 and B2 were supplemented in the soil of 20 plots (1 m²) at a dose of 4 kg/m². C1 and C2 (10 plots each) served as control plots. The plots were automatically irrigated and fertilizer was not applied. The B1-supplemented plots exhibited a significant 84.58% increase in dry corn production per square meter and a 93.16% increase in corn wet weight (p << 0.001). Corn production was no different between B2-supplemented, C1, and C2 plots (p > 0.01). The weight of cobs from B1-supplemented plots was 62.3%, which was significantly higher than that of cobs from C1 and C2 plots (p < 0.01). The grain weight increased significantly by 23% in B1-supplemented plots (p < 0.01) and there were no differences between B2-supplemented, C1, and C2 plots. At the end of the treatment, the soil of the B1-supplemented plots exhibited increased levels of sulfate, nitrate, magnesium, conductivity, and saturation percentage. Based on these results, the economic sustainability of this application in agriculture was studied at a standard price of €190 per ton of biochar. Amortization of this investment can be achieved in 5.52 years according to this cost. Considering the fertilizer cost savings of 50% and the water cost savings of 25%, the amortization can be achieved in 4.15 years. If the price of biochar could be reduced through the CO₂ emission market at €30 per ton of non-emitted CO₂, the amortization can be achieved in 2.80 years. Biochar markedly improves corn production in the Mediterranean climate. However, the amortization time must be further reduced, and enhanced production must be guaranteed over the years with long term field trials so that the product is marketable or other high value-added crops must be identified.     

Solar Light Active Graphitic Carbon Nitride/Biochar Nanocomposite for RhB Dye Degradation

In this work, nanocomposite graphitic carbon nitride/biochar is successfully prepared by physical mixing method to achieve efficient charge separation and photodegradation of RhB dye under sunlight. The biochar is synthesized by heating biomass in muffle furnace in an inert atmosphere. The graphitic carbon nitride is prepared using melamine as a precursor and heating it in a muffle furnace in air atmosphere. The structural characterizations FTIR and X-ray diffraction are done to confirm the functional groups and crystallography of prepared samples. The photodegradation of RhB dye by nanocomposite is analyzed using a UV–visible spectrophotometer under solar irradiation. It is found that the RhB dye is completely reduced by the nanocomposite in less than 6 min in the presence of sunlight. The kinetic study confirms the photodegradation of RhB dye is first order reaction and rate constant is found to be 0.31 min⁻¹.     

一步热解法制备Cu/Fe双金属生物炭复合材料及其高效吸附Pb2+性能

使用一步热解法制备了 Cu/Fe双金属生物炭复合材料(BC@Cu/Fe-X,X=3、5、10)和 Fe生物炭复合材料(BC@Fe)。考察了Cu掺杂量对BC@Cu/Fe-X吸附Pb²⁺的影响,确定最佳掺杂比例。结果显示BC@Cu/Fe-5吸附Pb²⁺性能最好。考察了吸附时间、Pb²⁺浓度、pH、背景离子、空气中老化等实验条件对 BC@Cu/Fe-5 吸附 Pb²⁺的影响。通过动力学、热力学数据拟合分析了BC@Cu/Fe-5吸附Pb²⁺的行为,利用X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、傅里叶变换红外光谱(FTIR)等表征手段解析了BC@Cu/Fe-5吸附Pb²⁺前后特征峰变化。BC@Cu/Fe-5吸附Pb²⁺的机理如下：大约42%的Pb²⁺被还原为Pb⁰,33%的Pb²⁺形成PbO/Pb(OH)₂,25%的Pb²⁺与O—H、C—O、C=O、COO、Fe—O等官能团形成配合物。Cu掺杂可以提高Fe还原Pb²⁺的能力。     

柚子皮制备磁性生物炭的表征及其对水中氯胺酮的检测

该研究以柚子皮为原料,制备了性能优良的磁性生物炭吸附剂,建立了快速检测氯胺酮的磁性固相萃取/超高效液相色谱-串联质谱法。扫描电镜和振动样品磁强计表征结果表明成功合成了磁性生物炭。采用单因素实验优化了吸附剂用量、吸附时间、溶液pH值,并采用Box-Behnken设计实验考察了解吸剂比例、解吸体积、解吸时间对水中氯胺酮回收率的影响。结果表明,在1～100μg·L^-1范围内,氯胺酮标准曲线的相关系数r> 0.999,检出限为0.263μg·L^-1,定量下限为0.878μg·L^-1。方法在不同水样中的加标回收率为84.0%～99.9%,日内和日间相对标准偏差分别为0.40%～3.4%和0.25%～1.9%。所建立的方法操作简便,准确高效,灵敏度高,适用于水中氯胺酮的检测。     

不同固废及其处理产物对黄骅港盐碱土的改良效果

[目的]探究不同固废及其处理产物对盐碱土的改良效果,促进固废消纳的同时为渤海湾盐碱地治理提供理论依据.[方法]以河北省沧州渤海新区黄骅港盐碱土为研究对象,通过土壤改良和盆栽试验,分析对照组(CK)、炉渣+煤矸石(S10、S50和S100)、生物炭(C10、C50、C100)和木醋液(V300、V100和V50)对土壤盐...     

城市绿地废弃物生物炭制备与应用前景

通过阐述生物炭的制备、表征、负载材料与应用的现状,探讨以城市绿地植物废弃物为原料制备生物炭及其复合材料的应用前景,提出生物炭研究发展方向,以期为生物炭资源高效利用提供参考.     

一种多孔氮掺杂生物炭的制备及对四环素吸附性能——创新型实验设计

为了拓展农业院校应用化学和材料化学专业高年级学生的学科视野,提高化学实验课程的高阶性、创新性和挑战度,通过科教融合,设计了一个创新性实验—利用汉麻废弃物制备多孔氮掺杂生物炭及对四环素吸附性能。实验内容包括氮掺杂多孔生物炭的制备、形貌结构和性质表征、吸附性能和稳定性的测试以及吸附动力学拟合与机理探索等。该实验具有化学、材料学与农业科学和生物科学相结合的特点,创新性强、操作简便,可供同类高校的同行借鉴。将农林废弃物的回收利用的科研成果应用于教学实践,可以突出专业特色,提升化学类专业学生的科技创新思维、环境保护意识和综合实践能力。     

受污染水稻秸秆热解产物中镉含量及溶出性研究

以镉污染土种植水稻秸秆为原料, 通过500℃不同时间(10~720min)处理制备秸秆热解产物(生物炭和秸秆灰), 测定产物中镉的含量及其溶出性. 结果表明, 水稻秸秆经热解处理后挥发镉总量的29.6%~48.4%; 样品产率随热解时间的增加而下降; 单位质量生物炭和秸秆灰中镉含量为2.35~7.05mg·kg-1和15.0~16.4mg·kg-1, 分别是水稻秸秆中镉含量(0.948mg·kg-1)的2.5~7.4倍和15.8~17.3倍; 通过不同提取剂得到镉溶出率由低到高依次为0%~43.2%(采用0.01mol·L-1 CaCl2提取)、0%~44.3%(采用Toxicity Characteristic Leaching Procedure提取)、28.8%~58.8%(采用1mol·L-1 pH5.0乙酸-乙酸钠单次提取)、35.1%~98.4%(采用1mol·L-1 pH5.0乙酸-乙酸钠连续4次提取); 随着热处理时间的延长, 样品中镉溶出率逐渐降低; 由于热解过程中镉的挥发和形态转变, 水稻秸秆转变为生物炭和秸秆灰后镉的可溶出总量(采用1mol·L-1 pH5.0乙酸-乙酸钠连续4次提取)由0.933mg·kg-1降至0.223~0.384mg·kg-1, 表明受镉污染的水稻秸秆热解转化为生物炭和秸秆灰可以有效缓解镉潜在的溶出风险.     

新型微波技术再生载甲苯活化秸秆炭

采用微波加热制备的活化秸秆炭作为吸附剂,通过微波法和电加热法对载甲苯活化秸秆炭进行再生。在确保再生率99%以上的前提下,测定了这两种方法的加热时间、再生效率和能耗等参数。结果表明：经过5次吸附-微波辐射再生之后,吸附量基本保持原有新鲜活化秸秆炭吸附量的为33%;恒功率微波加热法、恒温微波加热法和电加热法所需要的时间分别为1、10和120min;从能耗角度看,微波再生法恒功率（600W）和恒温（150℃）的能耗分别为4.5和9.0kJ/g,而电加热法的能耗则为36kJ/g。因此,微波再生法是一种节能、环保和高效的再生方法,为工业化应用奠定了基础数据。