富芳烃重油组分结构调变对中间相沥青形成的影响机制

对重油富芳烃组分转化为次生沥青及其氢化改性沥青的热转化行为进行了比较，并对热转化过程中体系化学结构组成特征对中间相形成的影响进行了研究。采用红外光谱及氢核磁共振波谱，对比分析了次生沥青及其氢化改性沥青的化学结构组成特征；借助偏光显微镜、X射线衍射，考察了两体系中间相沥青的形成过程。结果表明：控制体系短烷基侧链含量可有效抑制过度炭化的发生，提高炭化产物的微观有序度；短烷基侧链可以持续稳定释放出小分子自由基，对大分子自由基反应进行调控，显著提升炭化产物微观结构的均一性。     

铬酸钠碳化母液制备氢氧化铬工艺优化 及三氧化二铬粒度分布的影响

研究了利用铬酸钠碳化母液制备氢氧化铬工艺优化及三氧化二铬粒度分布的影响，主要考察了恒温温度、氢氧化铬洗涤方式对产品质量的影响；还考察了在固定煅烧条件下，铬酸钠含量对三氧化二铬颗粒形貌的影响以及铬酸钠碳化母液碳化率与三氧化二铬粒度分布的关系。结果表明，随着铬酸钠碳化母液碳化率的提升，Cr（Ⅵ）达到最大还原率时所需恒温温度下降，经过3次洗涤的氢氧化铬滤饼煅烧后铬酸钠质量分数为13%~15%，制备的三氧化二铬呈类球体，颗粒粒径均匀，洗涤烘干后各项参数指标均优于GB/T 20785—2006《氧化铬绿颜料》。通过增加原料碳化率，三氧化二铬颗粒的中位径D50随之增大，在碳化率为39.87%时制得的三氧化二铬中位径D50为 3.13 μm，粒度分布为典型的正态分布，其特征粒径值均符合高端氧化铬绿产品的技术要求。     

Preparation and Adsorption Properties of Biomass Activated Carbon from Ginger Stems

Biomass activated carbon(BAC) was produced from ginger stems by carbonization and activation presented high specific surface areas and mesoporous structures. The carbonization temperature of the ginger stems were controlled within 500～900℃. The optimal carbonization condition is as follows: carbonization temperature of 700℃, carbonization time of 6 h. The determined optimum activation condition is: temperature of 800℃, activator of KOH and carbonized product/alkali ratio of 1:4(w/w). The carbonization yield, BAC yield and Brunauer-Emmett-Teller(BET) surface area were measured and the adsorption performance of BAC to nitrogen was investigated. The results showed that the nitrogen adsorption isotherm curve was as type I isotherm. It was finally determined that the BET surface area was 660 m~2/g under the abovementioned optimal conditions of carbonization and activation. The FESEM analysis indicates that the obtained BAC is of micropore structure.     

草酸改性甘蔗渣炭的制备及其对Cr(Ⅵ)的吸附特性

以甘蔗渣（OB）为原料，先在空气氛围下高温炭化制得甘蔗渣炭（CB），再经草酸改性制得草酸改性甘蔗渣炭（COB），采用SEM、FT-IR和氮气吸附-脱附等温线对3种样品进行表征，并考察了OB、CB和COB对模拟废水中的Cr（Ⅵ）的吸附效果。结果显示：3种样品比表面积大小为COB>CB>OB，其中COB的比表面积为240.67 m²/g，总孔容为0.138 cm³/g，平均孔径为2.30 nm；CB以及COB较OB的孔隙结构更发达、含氧官能团种类及数量明显增加，吸附能力提高。吸附实验结果表明：对Cr（Ⅵ）的吸附量表现为COB>CB>OB，在pH值1、投加量0.6 g、吸附时间100 min、吸附温度25℃和Cr（Ⅵ）质量浓度50 mg/L条件下COB对Cr（Ⅵ）的去除率为99.1%。吸附热力学及动力学结果显示：Langmuir等温吸附模型能更好地反映吸附过程，吸附过程遵循准二级动力学模型，表明甘蔗渣炭对Cr（Ⅵ）的吸附主要为化学吸附的单分子层吸附。     

Synthesis of Humin-based Carbon Quantum Dots and Luminescent Properties

The unique properties of carbon quantum dots(CQDs) make them promising materials in many fields. Herein, we present a facile method for the preparation of photo-luminescent CQDs using humins as the carbon precursor for the purpose of providing a high value-added solution for this "biomass conversion process waste". The structure of the CQDs was analyzed, and the effects of reaction temperature and time on the CQDs' fluorescence were investigated. The results showed that humins were effectively carbonized during the reaction. The fluorescence intensity of humin-based CQDs initially increased with reaction temperature and time, and subsequently decreased beyond 200℃ and 4 h. Polyaromatic structures and hydrophilic groups such as O—H, C—O, —COOH and C==O groups exist in the CQDs. The huminbased CQDs have the dimension of 3～7 nm with an average size of about 5.5 nm. The highest emission intensity of blue/cyan fluorescence light at 440 nm is achieved on the excitation with UV light at the wavelength of 330 nm.     

Carbonaceous microsphere-based superabsorbent polymer as filler for coating of NPK fertilizer: Fabrication,properties, swelling,and nitrogen release characteristics

Recently, the use of controlled release fertilizers in agriculture has resulted in huge benefits in plant growth and cultivation. Superabsorbent polymer (SAP)-coated fertilizers have the added advantage in retaining water in soil after irrigation and also reduce the nutrient release rate from soil in a controlled manner. This study aimed to produce a nitrogen–phosphorus–potassium (NPK) fertilizer coated with superabsorbent carbonaceous microspheres polymer (SPC) by inverse suspension polymerization method with water-retention and controlled release properties. Two sets of experiments were conducted: (1) three different weight percentages and (2) different materials. NPK coated with SPC showed increasing water-retention ability with respect to carbon microsphere percentages and retains >80% water at the 30th day of experiment compared with pure NPK and NPK coated with SAP. The slow release behavior of all samples was investigated by induced coupled plasma mass spectrometry spectrometry and results showed that NPK coated with SAP and SPC has a low release rate with <50% nutrient release compared with uncoated NPK at the 30th day. The release mechanism kinetics of NPK coated with SAP and SPC were studied based on the Kosmeyer–Peppas model. The mechanisms approached Fickian diffusion-controlled release as the n value for both samples was less than 0.5. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48396.     

Hydrothermal Carbonization of Sewage Sludge: Analysis of Process Severity and Solid Content

Hydrothermal carbonization of sewage sludge was carried out with the aim to evaluate the influence of process severity and initial solid content. Response surface methodology was applied to model yield and C yield responses. Enhanced dewaterability performance was recorded under mild processing conditions. The treatment promoted concentration and immobilization of Pb, Cd, Ni, Zn, and Cu. Variation of the solid content showed a stronger influence than severity on average yield and C yield. Higher heating values (HHVs) and energy retention efficiencies (EREs) of hydrochars obtained at the lowest solid content displayed the lowest values. Hence, the energy requirements of a first dewatering step should be compared with the related improvement in terms of HHV and ERE when sludge is used as feedstock.