A novel strategy based on ultrasonic pretreatment and enzyme-assistence was proposed in this study to enhance short-chain fatty acids (SCFAs) production from anaerobic fermentation (AF) of waste activated sludge (WAS). The impacts of ultrasonic frequency (20 - 40 kHz), ultrasonic amplitude (60 - 90 %), and treatment duration (0 - 8 min) on sludge solubilization, as well as different enzymes (lysozyme, alpha-amylase, cellulase, and blended enzyme) on SCFAs production were assessed. The results showed that the optimal condition for ultrasonic pretreatment to enhance sludge solubilization was ultrasonic frequency of 20 kHz, amplitude of 80 %, and treatment duration of 5 min. Scanning electron microscope (SEM) and particle size distribution revealed that ultrasonic pretreatment effectively destructed EPS and sludge floc structure. The addition of enzymes enhanced SCFAs production, with the effects following the order of blended enzyme > lysozyme > cellulase > alpha-amylase > control. The maximum SCFAs accumulation for the enzyme-added systems was obtained on the 4th day, which were 1.81 - 3.41 times of that in the control system (8th day). Microbial community structure analysis disclosed that the functional microorganisms were strengthened by the addition of enzymes. The enrichment of phyla Firmicutes and Bacteroidetes in the enzyme-added systems, with enriched acidogenic genera (e.g. Propionispira) in the blended enzyme system and hydrolytic genera (e.g. Romboutsia) in the lysozyme system, hinted the mechanism of SCFAs production enhancement by enzymes.

The important intermediate thiothiamine for Vitamin B1 production is often challenged by issues related to mixed polymorphs and needle-shaped crystal morphology in industrial production. These challenges can be effectively addressed through crystal engineering strategies. In this study, the key factors affecting the crystal form were investigated in reactive crystallization. Subsequently, the reactive crystallization process was monitored online using in-situ ATR-FTIR and FBRM techniques. It was determined that crystallization process is the rate-limiting step throughout the reactive crystallization process. Various factors affecting the crystal morphology were identified. Through process control and optimization, a product was achieved with a filtration time reduced by over 60% and a moisture content reduction of >20%. Overall, this study provides valuable insights from a crystal engineering perspective to address the poor powder properties.

抗生素的过度使用对环境造成了持久性的污染，光电催化是降解抗生素的环保、高效技术，其中光电极的设计尤为重要。为提高抗生素降解速率，采用电化学还原和光还原法制备了Ag-Ti3+-TiO2纳米锥复合光电极，并用于模拟可见光照射下光电催化降解四环素的过程，考察其光电催化性能。结果表明，由于Ti3+自掺杂和Ag纳米颗粒的局域表面等离子体共振效应，复合电极有效地抑制了光生电子-空穴对的复合，并表现出更低的电荷转移电阻，提高了光电催化性能。复合光电极在可见光照射下，90 min后可降解87.9%的四环素，且5个循环后降解率保持在82.5%。这些结果表明，Ag-Ti3+-TiO2纳米锥复合光电极具有高降解效率、良好的稳定性和可持续的循环利用性，有望实现高效环保地光电催化降解抗生素。

Sludge anaerobic digestion promoted by enzymes has the advantages of mild reaction,high efficiency and environmental protection etc.However,the difficulty of recovery and poor catalytic stability seriously restrict its ap-plication.Enzyme immobilization is the key to solve the above problems.A new type of polyvinyl alcohol(PVA)car-rier was prepared by Noria and polyethylenimide(PEI)co-deposition.The effect of lysozyme immobilized with Noria-PEI modified PVA carriers on the efficiency of sludge anaerobic fermentation for VFAs production was studied.The results showed that immobilized lysozyme could enhance sludge fermentation to promote SCOD,and SCOD reached the highest concentration of 2 892.4 mg/L within 36 h,which was 3.4 times higher than in the blank(day 6).VFAs concentration peaked at 2 130.8 mg/L on day 4,mainly comprised of acetic acid and propionic acid,accounting for 61.8%-80.7%.The average particle size and specific surface area of sludge in the immobilized enzyme system were 42.957 µm and 0.413 m2/g,indicating that immobilized enzyme enhanced the hydrolysis of granular sludge.Micro-bial community analysis showed that the hydrolytic acid-producing phyla of Firmicutes,Proteobacteria and Bacteroi-des accounted for high proportion in the immobilized enzyme system.At the genus level,Macellibacteroides,Petri-mona,Lactobacillu,and Clostridium_sensu_stricto_1 were the main genera,which revealed the mechanism of en-hanced VFAs production by the immobilized enzyme at microscopic level.

A high-performance MnO2-coated Ti-based electrocatalytic membrane(MnO2/Ti) was prepared by a simple and controllable electrodeposition method. The morphology, elemental content, valence distribution and electrochemical impedance of the prepared MnO2/Ti membrane were systematically characterized, as well as cyclic voltammetric AC tests. The effects of flow rate and current density on the water treatment performance of the MnO2/Ti membrane were investigated. The results showed that MnO2 was uniformly distributed on the surface of Ti membrane,and electrodeposition MnO2 can significantly improve the electrochemical activity and enhance the electrocatalytic oxidation performance of Ti membrane, which could improve the self-cleaning ability of Ti membrane. The emulsified oil removal efficiency was as high as 91% under the operating conditions with current density of 10 mA/cm2 and flow rate of 1.5 mL/min. In addition,the MnO2/Ti membrane showed good stability and reusability. The oxidation mechanism showed that the MnO2/Ti membranes had direct and indirect oxidation activities during the electrocatalytic treatment process, and MnO2 coating could improve the direct oxidation capacity and ·OH, O2·- yields of the Ti membrane.

采用超声和生物酶联用技术处理剩余污泥以促进污泥厌氧发酵产酸,实现污泥资源化.首先,以天津市某污水处理厂二沉池剩余污泥为处理对象,采用单因素实验考察了超声预处理过程中处理时间、超声频率、超声振幅对剩余污泥溶出SCOD的影响,结果表明,超声预处理剩余污泥的最佳处理条件为处理时间 5 min、超声频率 20 kHz、振幅 80%,此条件下,污泥溶出SCOD为 407.5 mg/L.之后向经超声处理后的剩余污泥中分别投加污泥质量 5%的α-淀粉酶、纤维素酶、溶菌酶和复合酶进行厌氧发酵,以探究生物酶对剩余污泥厌氧消化的影响,结果表明,在温度 35℃下,复合酶对于污泥厌氧发酵产酸效果最好,污泥溶出SCOD在第 2天增加 2384.9 mg/L,在第 4天产酸量达到最大值 1465.8 mg/L,其中乙酸量为 1058.6 mg/L,丙酸量为 136.0 mg/L.溶菌酶效果优于其他单酶,SCOD第 2天增幅达 1840 mg/L,在第 4天产酸量达 1240.4 mg/L,其中乙酸量为 406.4 mg/L,丙酸量为524.3 mg/L.

In situ combustion of heavy oil is currently the most suitable thermal method that meets energy consumption and carbon dioxide emission requirements for heavy oil recovery. The combustion catalyst needs to perform multiple roles for application; it should be capable of catalyzing heavy oil combustion at high temperatures, as well as be able to migrate in the geological formation for injection. In this work, a hyperbranched polymer composite nanometal fluid was used as the injection vector for a heavy oil in situ combustion catalyst, which enabled the catalyst to rapidly migrate to the surface of the oil phase in porous media and promoted heavy oil cracking deposition at high temperatures. Platinum (Pt) nanoparticles encapsulated with cetyl-hyperbranched poly(amide-amine) (CPAMAM), with high interfacial activity, were synthesized by a facile phase-transfer method; the resulting material is called Pt@CPAMAM. Pt@CPAMAM has good dispersion, and as an aqueous solution, it can reduce the interfacial tension between heavy oil and water. As a catalyst, it can improve the conversion rate during the pyrolysis of heavy oil in a nitrogen atmosphere. The catalyst structure designed in this study is closer to that exhibited in practical geological formation applications, making it a potential method for preparing catalysts for use in heavy oil in situ combustion to resolve the problem of catalyst migration in the geological formation.

用十二烷基三甲基氯化铵对纳米蒙脱土进行有机改性得到改性蒙脱土(OMMT).用自由基聚合法合成丙烯酸十八酯-乙酸乙烯酯-顺丁烯二酸酐三元聚合物,然后将其与OMMT通过熔融共混法制得纳米复合防蜡剂,利用FTIR,GPC,XRD,TG,SEM,DSC,POM等方法分析了试样的结构,并考察了防蜡剂对模型油的防蜡降黏效果.实验结果表明,在添加量为 300 mg/kg时,纳米复合防蜡剂W-7 可使蜡含量 10%(w)的模型油的防蜡率、降黏率分别达 94.9%和 98.2%.在添加量为 500 mg/kg时,纳米复合防蜡剂W-2 可使蜡含量 20%(w)的模型油的防蜡率、降黏率分别达 94.6%和 99.2%.加入纳米复合防蜡剂后,模型油的析蜡点降低,有效防止了石蜡晶体聚集.

Most of the amino acids grow in needle-like or sheet-like crystal habit, which have problems such as low bulk density and poor fluidity, and seriously affect the post-processing process of the product. Therefore, it is of great significance to control the crystal habit of amino acids. Additives are directly effective in regulating the crystal habit of amino acids and are widely used in industrial production. In this paper, the mechanism of additives on the growth of amino acid crystals is reviewed from the perspectives of inhibiting or promoting crystal growth. There are two main mechanisms for the inhibition of crystal growth by additives: one is that the additive molecules are adsorbed on the crystal surface, which hinders the diffusion and aggregation of solute molecules, the other is that the additive molecules are embedded in the crystal lattice and occupy growth sites. The mechanism of additive promoting crystal growth is that the additive accelerates the aggregation rate of solute molecules on the crystal surface, roughens the crystal surface and reduces the energy barrier removal of the solvent layer. Finally, we propose the prospect of directionally regulating the amino acid crystal growth through molecular design of additives from the perspective of crystal engineering.

抗生素滥用造成了严重的环境污染并危害人体健康.光电催化技术(PEC)以电化学辅助光催化反应,在光照下通过向光催化剂施加外部偏压抑制光生电子-空穴对的复合,提高自由基浓度,以此显著提高系统对有机物的降解速率,具有环保节能、氧化能力强、操作方便等优势,已成为去除抗生素等难降解污染物最有前景的高级氧化技术之一.对PEC降解抗生素的进展进行了全面综述,介绍了PEC原理,重点总结了电极材料改性方法及其性能,阐述了PEC降解抗生素的最新应用及降解中偏置电压、pH、电解液、光源等对抗生素降解率的影响,最后对PEC降解抗生素的前景和挑战进行了总结和展望,以期为应用光电催化技术高效处理抗生素废水的研究提供参考.

Sulfide in refinery sewage is a malodorous substance.It is volatile and may result in obvious odor in the plant air.This may endanger the health of operators and cause corrosion of equipment.And sulfide has adverse effects on downstream biochemical treatment.This paper summarizes the development status,application and respective advantages and disadvantages of different desulfurization and deodorization technologies for sulfur-containing sewage at home and abroad.It highlights the characteristics of catalytic oxidation desulfurization technology.Since the sulfur content of crude oil is increasing year by year and there’s increasing sulfur content in refinery sewage,the environmental pressure on refineries is increasing accordingly.Hence the development of catalytic oxidation sewage desulfurization and deodorization technology using air as the oxidation source is promising,but there are also certain technical risks and challenges in the development process.

A series of hyperbranched polyethyleneimine (h-PEI) functioned with terminal amine groups is synthesized to remove oil from O/W emulsion. The demulsifier dehydration rate of h-PEI is systematically evaluated with the subsidiary facilities of DLS analysis, digital tensiometer and UV-vis spectrophotometer. The results indicate that h-PEI demulsifier displays satisfactory demulsification (the oil removal rate > 90%) with small dosage (< 80 mg L-1) and short settling time (< 30 min). The relatively short equilibrium time and great demulsification are ascribed to the amine groups and the molecular weight. On one hand, the hyperbranched macromolecules with amine groups can rapidly diffuse and adsorb to the oil-water interface, on the other hand, the molecules with adequate molecular weight are apt to flocculate, coalesce oil droplets, and then obtain high-efficient demulsi-fication. The exceptional demulsification performance of h-PEI exhibits a potential role application in industrial water treatment or the petroleum demulsification industry.

高浓度炼化污水中污染物浓度很高,且含有抑制微生物活性或者毒性的物质如酚类、醛类等,无法用传统生化法处理.本试验考察了环流生化反应器处理该污水的效果,主要考察CODCr和氨氮的去除效果、活性污泥的沉降性能及装置的抗冲击性.结果表明,CODCr去除率约为90％,氨氮去除率达到94％以上,短时间进水波动超过20％左右时,恢复正常后出水可在2～3d恢复到原水平.该装置解决了因为生物抑制性或者毒性大的污染物浓度高导致的无法生化处理的问题,且相比其他处理方法成本更低、污泥负荷更高、处理效率更快,作为预处理方法出水可生化性不受影响等.

制备了活性炭基酞菁钴催化剂,通过静态催化氧化活性测试、模拟含硫污水处理实验考察了催化剂对污水中硫化物的去除性能,并对催化剂进行了比表面积与孔径分布(BET)、扫描电子显微镜(SEM)以及红外光谱(FTIR)表征.结果表明:负载后活性炭的平均孔径由1.79 nm增加至3.76 nm,表面不规则程度增加,较佳的酞菁钴负载量为1％;在常温、常压条件下,氧化源为空气时,催化剂连续处理污水近45 h,硫化物去除率仍高于98.5％;脱硫实验后,部分氧化产物单质硫以丝状在催化剂外表面聚集,催化剂中的酞菁钴分子未发生结构变化,催化剂稳定性良好.

采用移动床生物膜反应器(MBBR)联合管式膜构建气提式管式膜MBR体系用以处理生活污水,考察了曝气对污水处理效果、膜内气液流态及膜过程的影响,探讨了污泥特性的变化及其对膜污染过程的影响机制.结果表明,气提式管式膜MBR体系下膜出水DO浓度高于混合液,且随着曝气量由50L·h-1提高至150L·h-1,管式膜内气含率由0.33增至0.60并呈"活塞流"流态,操作周期由6～7d延长至17d,膜污染速率由1.54 kPa·h-1降至0.21kPa·h-1,临界通量显著增大;同时,MBBR混合液中EPS总量呈减小趋势,但MBBR内悬浮污泥粒径变小,且膜表面EPS中PN/PS比例显著高于MBBR混合液.膜表面污染阻力构成分析表明,气提式管式膜MBR体系下容易发生膜孔堵塞,膜污染以不可逆污染阻力为主.

α-二亚胺镍催化剂作为一种后过渡金属配合物,具有独特的"链行走"机理,不仅可以将乙烯转化为高度支化的聚烯烃弹性体,而且只需改变配体结构和反应条件就能有效控制聚合物的微观结构.本综述以合成聚烯烃弹性体为目的,介绍了α-二亚胺镍配合物近五年的最新进展.

Novel heavy atom free 5,5-dioxoyphenothiazine-based ?D?A?D? emitters with aggregation-induced emission (AIE), room-temperature phosphorescence (RTP), white light emission and dual-mode mechanochromic luminescence (MCL) characteristics have been designed and synthesized. Impressively, DCzCs and DCzCs-Et showed persistent RTP (pRTP) in the crystalline state with lifetimes of 528 ms and 137 ms in air, respectively. DCzCs-Ac exhibited white light emission with a CIE coordinate of (0.25, 0.26), due to the dual emission of fluorescence and phosphorescence. Detailed studies have shown that through simply functional group modification on the acceptor skeleton to modulate the molecular structure and intermolecular interactions, we fine-tuned the optical properties of the luminogens and realized white light emission. The dense crystal packing was proved to be closely related to the phosphorescence of the system and the special dual-mode MCL behavior was attributed to the conversion of crystalline-amorphous state under external force.

针对瓶试法评定破乳剂存在的精确性较差、人为误差等不确定性问题,优选室内合成的具有合适取代度的超支化聚醚型破乳剂(HPG-MA)和具有合适多乙烯多胺的超支化聚酰胺-胺型破乳剂(h-PAMAM),采用紫外可见分光光度法测定其破乳性能.首次采用动态光散射法和紫外-可见分光光度法,并结合界面张力的变化规律,详细研究了其破乳机理.结果表明,2种超支化聚合物破乳剂的脱油率均高于85％,超支化聚合物破乳剂的破乳机理为絮凝聚结机理和顶替置换机理.

以超支化聚缩水甘油(HPG)和甲基丙烯酸缩水甘油酯(GMA)进行酯交换反应,得到一系列超支化聚缩水甘油甲基丙烯酸酯(HPG-MA)破乳剂,考察了添加量、破乳温度、沉降时间及相对分子质量对破乳性能的影响,并探究动态界面张力和破乳过程中油滴的破裂速率常数的变化,分析其破乳机理.结果表明,在60℃、沉降时间为40min、破乳剂的添加量为2000mg/L时,其脱油率达到90％.与商用破乳剂相比,超支化聚缩水甘油甲基丙烯酸酯因具有独特的超支化多位点结构,用作破乳剂时界面活性高、沉降时间短.

分别采用多级串联粒子电极和二维平板电催化、三维粒子电极电催化工艺处理初始COD为500 mg/L的苯酚溶液,对出水COD及电流效率进行测定分析.结果表明,保持相同吨水电耗和电流密度,二维平板电极、三维粒子电极、多级串联粒子电极出水COD分别为56、170、34 mg/L,去除率分别为88.8％、66.0％、93.2％.多级串联粒子电极吨水电耗、电流效率、反应速率优于二维平板电极和三维粒子电极,反应符合一级动力学.