Acid Blue 25 adsorption on base treated Shorea dasyphylla sawdust: Kinetic, isotherm, thermodynamic and spectroscopic analysis

The potential of base treated Shorea dasyphylla (BTSD) sawdust for Acid Blue 25 (AB 25) adsorption was investigated in a batch adsorption process. Various physiochemical parameters such as pH, stirring rate, dosage, concentration, contact time and temperature were studied. The adsorbent was characterized with Fourier transform infrared spectrophotometer, scanning electron microscope and Brunauer, Emmett and Teller analysis. The optimum conditions for AB 25 adsorption were pH 2, stirring rate 500 r/min, adsorbent dosage 0.10 g and contact time 60 min. The pseudo second-order model showed the best conformity to the kinetic data. The equilibrium adsorption of AB 25 was described by Freundlich and Langmuir, with the latter found to agree well with the isotherm model. The maximum monolayer adsorption capacity of BTSD was 24.39 mg/g at 300 K, estimated from the Langmuir model. Thermodynamic parameters such as Gibbs free energy, enthalpy and entropy were determined. It was found that AB 25 adsorption was spontaneous and exothermic.     

Adsorption of Disperse Blue SBL dye by synthesized poorly crystalline hydroxyapatite

The present study has been undertaken to evaluate the adsorption in batch mode of a disperse dye (Disperse Blue SBL) by poorly crystalline hydroxyapatite synthesized by coprecipitation between Ca(NO_3)_2 and (NH_4)_2HPO4 reagents in aqueous solution at room temperature. The adsorption experiments were carried out to investigate the factors that influence the dye uptake by the adsorbent, such as the contact time under agitation, adsorbent dosage, initial dye concentration, solution temperature, and pH. The e...     

中国水泥排放清单及分布特征

本研究基于2018年在线监测数据等,分析中国水泥行业主要工序(窑头和窑尾)排口烟气浓度情况,自下而上建立了2018年中国高时空分辨率水泥行业大气污染物排放清单(high resolution cement emission inventory for China, HCEC).结果表明, 2018年中国水泥行业的PM、 SO₂和NO_x排放量分别为72 893、 92 568和878 394 t.从时间维度:2018年中国水泥行业主要工序烟气排口月均浓度逐步降低,蓝天保卫战成效显著.从区域维度:2018年京津冀及周边地区、长三角地区和汾渭平原,水泥窑年均排放浓度整体低于全国平均水平,但各城市排放浓度存在差异. 2018年安徽省水泥行业排放量最大,北京市和天津市水泥行业的单位面积污染排放强度最大.     

Decolorization of reactive Brilliant Blue KN-R by immobilized cells of Aspergillus ficuum

Aspergillus ficuum was immobilized with sodium alginate, and decolorization of Reactive Brilliant Blue KN-R was studied on immobilized and free Aspergillus ficuum. The optimal preparation condition of the strain immobilization was obtained by the orthogonal test, it is sodium alginate 3%, CaCl2 5%, wet mycelia 30 g/L, calcific time 8 h. It was found that the immobilized cells could effectively decolorize Reactive Brilliant Blue KN-R, the optimum temperature and pH were 33℃ and 5.0, respectively. The kinetics study of decolorization of immobilized cells showed that the decolorization of Aspergillus ficuum immobilized conformed to zero-order reaction model. The decolorization efficiency of immobilized cell compared with that of free cell in different physical conditions. Results showed that the decolorization of immobilized cells with mycelia had the best efficiency. The immobilized cells could be reused after the first decolorization.     

Decolourization of reactive brilliant blue KN-R by immobilized cells of Aspergillus ficuum

Aspergillus ficuum was immobilized with sodium alginate,and decolourization of Brilliant Blue NK-R was studied on immobilized and free Aspergillus ficuum.The optimal preparation condition of the strain immobilization was obtained by the orthogonal test,it is sodium alginate 3%,CaCl2 5%,wet mycelia 30g/L,calcific time 8h.It was found that the immobilized cells could effectively decolourize Reactive Brilliant Blue KN-R,the optimum temperature and pH were 33℃ and 5.0,respectively.The kinetics study of decolourization of immobilized eclls showed that the decolourization of Aspergillus ficuum immobilized conformed to zero-order reaction model.The decolourization efficiency of immobilized cell compared with that of free cell in different physical conditions.Results showed that the decolourization of immobilized cells with mycelia had the best efficiency.The immobilized cells could be reused after the first decolourization.     

焙烧态镁铝水滑石处理阴离子染料废水研究

采用传统过饱和双滴法合成出Mg/Al为3的碳酸根型水滑石(LDH),经500℃高温煅烧制备出焙烧产物(CLDH),用x-射线、红外光谱和电镜对它们进行了表征。分别考察了焙烧温度、反应时间、pH、投加量、反应温度和初始浓度等因素对焙烧态水滑石吸附酸性铬蓝K模拟废水效果的影响。结果表明,对于100mg/L的铬蓝K溶液,500℃焙烧态水滑石,投加量为0.06g,在pH=3.5左右,室温下反应1h,去除率最高可达98%以上。四次回收重复利用的CLDH对铬蓝K的去除率仍为90%以上,CLDH是一种良好的环保吸附材料。     

改进Fenton体系处理蒽醌染料的研究

以活性艳蓝KN-R作为研究对象,用UV/Fenton和solar/Fenton/草酸(H2C O4)体系对其进行处理,对反应体系的影响因素作综合的评价.得到处理蒽醌染料废水的最佳条件:dye(活性艳蓝KN-R):Fe2 :H2O2:H2C2O4为5:1:15:1.5,pH为3.0,反应时间为40 min.在最佳条件下,solar/Fenton/H2C2O4体系脱色率达到100%,COD和TOC去除率分别达到87%和66%以上.改进的Fenton方法能使难降解有机染料迅速脱色,矿化程度较高.并对此体系处理活性艳蓝KN-R废水的脱色过程进行动力学模拟,得到此反应为拟一级反应.     

Absence of status signalling by structurally based ultraviolet plumage in wintering blue tits (<Emphasis Type="Italic">Cyanistes caeruleus</Emphasis>)

Structurally based ultraviolet (UV)-reflective plumage parts can be important cues in mate choice. However, it remains largely unknown if UV plumage variation can also function as a signal of social status during competitive interactions. In blue tits (Cyanistes caeruleus), the UV-reflective crown plumage functions as a female mate choice cue that probably indicates male quality, as males with higher UV reflectance have been shown to have better chances of over-winter survival. Possibly, the UV crown plumage acts as a status signal in the competition over scarce food sources during winter. To test this idea, we related dominance of individuals at an artificial food source during adverse winter conditions to spectrophotometric measurements of their crown plumage. However, while controlling for the confounding effects of sex, age, and distance from territory, we found no significant effect of crown UV reflectance on dominance. Consistent with this result, we also found no relation between crown UV reflectance and over-winter survival. We conclude that the structurally based UV reflectance of the blue tit crown feathers plays little role in competition between individuals during winter despite its importance as a cue in mate choice.     

青霉菌对活性艳蓝 KN-R的吸附作用

研究了青霉菌(Penicillium X5)对活性艳蓝KN—R的吸附作用．通过对培养液的波谱分析和宏观现象的观察，结果表明，在72h内，脱色是由吸附引起的．当染料的浓度为100mg/L时，活菌体对染料的吸附率可达88．66％．本实验还研究了对实际应用和吸附过程有影响的几个因素，包括葡萄糖、NaCl、温度和pH.结果表明：葡萄糖浓度在0-20g／L时，随着葡萄糖浓度的增加，菌体的干重相应增加，说明对活性艳蓝KN—R的吸附具有促进作用，但浓度在10-20g／L时，吸附作用不显著；而随着NaCl浓度(0-2％)的增加，吸附率却显著降低．最佳脱色温度为25℃，pH为4．0．活菌体与死菌体的生物吸附均符合Langmuir方程，活菌体比死菌体具有更好的吸附性能．吸附在菌丝体上的染料可以用甲酵进行洗脱，菌丝球在下次使用前用蒸馏水冲洗至pH中性，此菌丝球可重复使用3次．固8表2参11     

Treatment of methylene blue-containing wastewater using microorganisms supported on granular activated carbon under packed column operation

We studied the feasibility of using biological granular activated carbon-packed column in treating methylene blue-containing wastewater. The granular activated carbon with immobilized microbes was packed into a column and fed with 3 liter methylene blue-containing wastewater daily. With initial 1350 mg/l of methylene blue and 1550 mg/l of chemical oxygen demand, it was observed that the colour and chemical oxygen demand removal efficiencies were 99 and 78%, respectively. The high treatment performance of the system could be due to the simultaneous adsorption and biodegradation processes and advantages of immobilized microbes compare to suspended cell system.