Efficient removal of Cr(Ⅲ)-carboxyl complex from neutral and high-salinity wastewater by nitrogen doped biomass-based composites

Heavy metals usually exist stably as the species of organic complexes in high-salinity wastewater.Therefore,their effective removal is challenging,especially when the initial p H is neutral.Herein,a novel nitrogen doped biomass-based composite(N-CMCS)was synthesized to remove the complexed heavy metal of Cr(Ⅲ)-carboxyl.The maximum adsorption capacity of Cr(Ⅲ)-Citrate(Cr-Cit)by N-CMCS under neutral p H(7.0)and high-salinity(200 mmol/L NaCl)condition was up to 2.50 mmol/g.And the removal performance remained stable after 6 times of regeneration.Combined with species and characterizations analysis,electrostatic attraction and hydrogen bonding were the main mechanisms for N-CMCS to remove Cr(Ⅲ)-carboxyl complexes.Dynamic adsorption indicated N-CMCS column could treat about 1300BV simulated wastewater and 350 BV actual wastewater with the concentration of effluent lower than1.0 mg/L.Furthermore,N-CMCS could remove a variety of complexed heavy metal ions under neutral p H,indicating the great potential in practical application.

Revealing the GHG reduction potential of emerging biomass-based CO_(2) utilization with an iron cycle system

CO_(2) utilization becomes a promising solution for reducing anthropogenic greenhouse gas (GHG) emissions. Biomass-based CO_(2) utilization (BCU) even has the potential to generate negative emissions, but the corresponding quantitative evaluation is limited. Herein, the biomass-based CO_(2) utilization with an iron cycle (BCU-Fe) system, which converts CO_(2) into formate by Fe under hydrothermal conditions and recovers Fe with biomass-derived glycerin, was investigated. The GHG reduction potential under various process designs was quantified by a multidisciplinary method, including experiments, simulations, and an ex-ante life-cycle assessment. The results reveal that the BCU-Fe system could bring considerable GHG emission reduction. Significantly, the lowest value is −34.03 kg CO_(2)-eq/kg absorbed CO_(2) (−2.44 kg CO_(2)-eq/kg circulated Fe) with the optimal yield of formate (66%) and Fe (80%). The proposed ex-ante evaluation approach not only reveals the benefits of mitigating climate change by applying the BCU-Fe system, but also serves as a generic tool to guide the industrialization of emerging carbon-neutral technologies.

Biomass-based biomimetic-oriented Janus nanoarchitecture for efficient heavy-metal enrichment and interfacial solar water sanitation

Interfacial solar steam generation(ISSG),involving the use of solar energy to evaporate water at the water-to-vapor interface,has presented prospects for the desalination and purification of water due to high energy conversion efficiency and low-cost freshwater generation.Herein,inspired by the aligned nanostructure of plants for efficiently transporting nutrient ions,we optimally design and construct a biomass-based Janus architecture evaporator with an oriented nanostructure for ISSG,using the ice template method,followed by biomimetic mineralization with the resource-abundant and low-cost biomass of the carboxymethyl cellulose and sodium alginate as the raw materials.Taking advantage of the oriented nanostructure allowing efficient transportation of water and coordination capacity of sodium alginate for effective enrichment of heavy-metal ions,the biomass-based Janus architecture shows much lower thermal conductivity and an ultrahigh steam regeneration rate of 2.3 kg m−2 h−1,considerably surpassing those of previously reported oriented biomass-based evaporators.Moreover,the biomass precursor materials are used for this Janus evaporator,guaranteeing minimum impact on the water ecology and environment during the regeneration process of clean drinking water.This study presents an efficient,green,and sustainable pathway for ISSG to effectively achieve heavy-metal-free drinking water.

生物质基泡沫材料的研究进展

本文综述了生物质基泡沫材料的研究进展,详述了生物质基泡沫材料的主要原料及种类(纤维素、木质素、淀粉和壳聚糖)、制备方法和性能(热学、力学和环境稳定性)的改善方法,以及其在建筑绝缘材料、包装材料和其他潜在领域的应用现状,并对其未来研发方向进行了展望。

基于磺化碳基固体酸的纤维素水解糖化研究进展

对磺化碳基固体酸制备原料及制备方法进行系统介绍,分析磺化碳基固体酸物理化学结构与其催化纤维素水解的构效关系,讨论碳基固体酸失活原因及分离回收方法。针对磺化碳基固体酸与纤维素间的传质限制,总结归纳先“降结晶、再水解”的纤维素高效水解策略。最后对磺化碳基固体酸的未来研究重点和前景进行展望,以期为促进磺化碳基固体酸在木质纤维素糖平台构建中的创新发展提供科学参考。

Sustainable production of high-energy-density jet fuel via cycloaddition reactions

Developing an energy supply-chain based on renewable biomass holds great potential to build a low carbon society.High-energy-density(HED)jet fuel,featuring unique fused/strained cycloalkanes,is of great significance for volume-limited military aircrafts,as their high density and combustion heat can extend flight duration and increase the payload.Therefore,the exploration of biomass-based routes towards HED fuel has drawn much attention over the past decade.Cycloaddition reaction features rapid construction of various carbocycles in an atom-and step-economical fashion.This elegant strategy has been widely applied in the manufacture of sustainable HED fuel.Here we carefully summarize the progress achieved in this fascinating area and the review is categorized by the cycloaddition patterns including[4+2],[2+2],[4+4],and[2+1]cycloadditions.Besides,the energy densities of the as-prepared biofuels and petroleumbased fuels(conventional Jet-A and advanced JP-10)are also compared.This review will provide important insights into rational design of new HED fuel with different ring-types/sizes and inspire the chemists to turn those literature studies into practical applications in military field.

Promoting role of Ru species on Ir-Fe/BN catalyst in 1,2-diols hydrogenolysis to secondary alcohols

Noble metal-based-bimetallic catalysts have been highly investigated and applied in wide applications including biomass transformation via regioselective C−O hydrogenolysis while further modification especially with noble metal is highly promising yet still under investigation.Herein,Ru was found as an effective modifier among the screened noble metals(Ru,Pt,Rh,Pd,Au,and Ag)for Ir-Fe/BN(Ir=5 wt%,Fe/Ir=0.25)catalyst in terminal C−O hydrogenolysis of 1,2-butanediol(1,2-BuD)to 2-butanol(2-BuOH).Only trace amount of Ru(up to 0.5 wt%)was effective in terms of high 2-BuOH selectivity(>60%)and activity(about twice).Larger amount of Ru species(3 wt%)highly enhanced the activity but gave low selectivity to 2-BuOH with by-products of terminal C−C bond scission.Optimized catalyst(Ru(0.5)-Ir-Fe/BN)was reusable at least 4 times and gave moderate 2-BuOH yield(47%)in hydrogenolysis of 1,2-BuD.The promoting effect of Ru addition(0.5 wt%)to Ir-Fe/BN on hydrogenolysis of various alcohols was also confirmed.Combining catalytic tests with various characterizations,the promotion mechanism of Ru species in trimetallic catalysts was clarified.The Ru species in Ru(0.5)-Ir-Fe/BN form alloy with Ir and are enriched at the interface with BN surface,and direct interaction between Ru and Fe was not necessary in Ru-Ir-Fe alloy.The interface of Ir and Fe on the surface of Ir-Fe alloy may work as active sites for 1,2-diols to secondary alcohols via direct C−O hydrogenolysis,in which Ru-modified Ir activates H_(2) to form hydride-like species.The activity of Ru species in C−C bond cleavage was highly suppressed due to the direct interaction with Ir species and less exposed to substrate.Larger loading amount of Ru species(3 wt%)led to the formation Ru-rich trimetallic alloy,which further works as active sites for C−C bond scission.

Hierarchical CoFe@N-Doped Carbon Decorated Wood Carbon as Bifunctional Cathode in Wearable Zn-Air Battery

Rechargeable Zn-air batteries(ZAB)have drawn extensive attention due to their eco-friendliness and safety.However,the lack of high-performance and low-cost oxygen redox reactions(OER and ORR)catalysts has become one of the main stumbling blocks in their development.Herein,we successfully fabricate a CoFe nanobubble encapsulated in nitrogen-doped carbon nanocage on wood carbon support(CoFe@NC/WC)via pyrolysis of a novel Prussian blue analog(PBA)/spruce precursor.The hierarchical CoFe@NC/WC catalyst exhibits an excellent potential difference of 0.74 V between the OER potential at 10 mA cm^(-2)and half-wave potential of ORR in 0.1 M KOH,comparable to recently reported preeminent electrocatalysts.Further,CoFe@NC/WC shows outstanding electrochemical performance in liquid ZAB,with a peak power density of 138.9 mW cm^(-2)and a specific capacity of 763.5 mAh g^(-1).More importantly,a bacterial cellulose nanofiber reinforced polyacrylic acid(BC-PAA)hydrogel electrolyte shows ultrahigh tensile-breaking stress of 1.58 MPa.In conjunction with the as-prepared CoFe@NC/WC catalyst,BC-PAA-based wearable ZAB displays impressive rechargeability and foldability,and can power portable electronics,such as electronic timer and mobile phone,in bent states.This work provides a new approach toward high-activity and low-cost catalysts for ZAB.

生物质基厚朴酚和糠醛对酚醛树脂的改性研究

为了减少化石能源的使用,选取生物质基厚朴酚和糠醛取代部分苯酚和甲醛,制备了改性酚醛树脂。通过傅里叶变换红外光谱仪,核磁共振波谱仪对改性酚醛树脂进行表征,考察了改性酚醛树脂的基础性能及固化后的力学性能。结果表明:厚朴酚和糠醛改变了酚醛树脂的分子结构,改性酚醛树脂的黏度和游离酚含量明显降低;经过固化后的改性酚醛树脂拉伸强度、冲击强度、弯曲强度分别提高18.6%、20.4%和24.9%。

生物质基胶黏剂的研究进展

我国的木材胶黏剂消耗量巨大,以丰富的生物质资源制备生物质基胶黏剂作为传统三醛树脂胶黏剂的补充具有重要的现实意义。本文综述了生物质原料在三醛树脂中的应用及生物质基胶黏剂的研究进展,展望了生物质基胶黏剂的发展趋势及研究方向,为我国生物质基胶黏剂行业未来发展提供参考。

现代林产化学加工技术的现状与发展趋势

生物质资源来源广泛,具有可再生性、结构多样性和碳中性等特点。目前,以生物质为原料的林产化工已成为继煤和石油化工之后最重要的化工产业之一。在对中国的林产化学工业发展历史概览的基础上,梳理总结了现代林产化学工业的发展,创新地提出了林产化学加工工程学科发展的能源化、材料化、食药化、饲料化、肥料化和基料化6个方向。其中,能源化中的生物质气/液/固体燃料的有效开发是实现碳达峰和碳中和的重要途径之一,而我国林产化工的传统研究领域制浆造纸、木本油脂、松脂化学等则从材料化找到新的突破和发展,相比前两者,食药化、饲料化、肥料化和基料化还有很大的发展空间。林产化学工业已迈入质量和效益持续提升发展新阶段,今后将在生物质资源高值化利用、全质利用技术创新、精深加工与应用、绿色低碳与生物技术融合、生物基材料与化学品创新应用,以及多学科交叉融合等方面实现突破,推动产业转型升级,构建绿色低碳循环发展新模式。

生物质炭材料活化过硫酸盐降解有机污染物的研究进展

作为经济、易得的含碳材料,生物质炭已应用于高级氧化领域。以硫酸根自由基为基础的高级氧化工艺是降解有机污染物的有效方法之一。本文综述了过硫酸盐的特点及其氧化降解有机污染物的反应原理,重点分析了生物质炭材料的非金属改性(氮掺杂、硼掺杂和硫掺杂)、金属改性、表面修饰等改性方式对其活化过硫酸盐降解有机污染物的影响,讨论了生物质炭基催化剂对典型有机污染物的降解效果与机理,并展望了生物质炭基材料在活化过硫酸盐降解有机污染物领域的技术挑战和发展前景。

碳基复合催化剂降解有机污染物研究进展

过硫酸氢盐高级氧化工艺是降解各种有机污染物的有效治理方法,高效、经济、环保的过硫酸氢盐催化剂是现阶段的研究热点。碳基催化剂作为环境友好、稳定性高的绿色催化材料,具有强吸附能力并且能够有效防止有毒金属离子的浸出和二次污染。本文阐述了碳基材料活化过硫酸盐的三种机理:自由基、非自由基以及两种机制并存的途径。详述了单一过渡金属和双过渡金属、非金属杂原子负载在碳基材料上形成的复合催化剂和生物质材料催化剂活化过硫酸氢盐对有机污染物的降解效果,对碳基催化剂用于活化过硫酸氢盐降解废水中有机污染物的研究方向进行了展望。

生物质基有机太阳能电池材料研究进展

有机太阳能电池(OSCs)具有成本低、可大规模溶液加工、轻量化和柔性等优势,近年来已引起人们的广泛关注,当前OSCs的最高光电转换效率已超过19%。然而,绝大多数OSCs材料主要是采用化石资源衍生物制造,这对OSCs的可持续发展构成了严重威胁。研究者已开展了大量关于生物质基光电材料的开发工作,并成功将这些材料用作OSCs的衬底、光敏活性层与载流子传输层。本文首先对OSCs的器件结构和工作原理进行了介绍,重点对木质素、纤维素、叶绿素等生物质基光电材料的制备及其在OSCs中的应用展开综述,最后对生物质基OSCs材料的发展方向做出了展望,旨在为后续的相关研发工作提供借鉴。

生物质基无铬鞣剂在可持续皮革制造中的研究进展

鞣制是使生皮变成革的关键工序。目前,铬鞣剂因其优良的性能仍占据鞣剂市场的90%。但是Cr3+存在转化为具有致癌性Cr6+的潜在危害,铬鞣废水的排放对生态系统的潜在风险不容忽视。因此,无铬鞣剂成为研究的热点。其中生物质材料因其来源广泛、可再生和生物可降解好等优点而备受关注。文章对多糖类、蛋白类等生物质材料进行了介绍,并对多糖、蛋白质的功能改性及其在皮革鞣制和复鞣的应用进行了归纳。同时,对生物质基鞣剂的发展前景及推广应用进行了展望。

充分挖掘生物质的能源和材料综合利用效能

利用生物质资源进行能源化利用和生产生物质基材料是实现减少碳排放的重要途径。我国每年产生生物质资源达到35亿吨,但是综合利用率不超过50%。主要的瓶颈在于利用方式单一化,造成成本高,无法推广和可持续发展。该文通过整理能源利用和材料利用的产业化工艺,提出生物质资源综合利用的可能性探讨。建议通过技术的联合、国家政策的推动等,促进生物质资源更加高值化利用,实现“双碳”目标的达成。

双功能炭基固体酸的制备及其催化纤维二糖醇解

以壳聚糖为碳源,通过金属浸渍、高温炭化制备负载铁的含氮活性炭(ACN-Fe),再进一步水热磺化制备了一系列金属负载型双功能炭基固体酸(ACN-Fe-SO_(3)H),并将其应用于催化纤维二糖醇解反应,利用X射线衍射(XRD)、拉曼(Raman)光谱、红外(FT-IR)光谱、N_(2)吸附/脱附、X射线光电子能谱(XPS)、电感耦合等离子体发射光谱(ICP-OES)和酸碱滴定等手段对催化剂进行了详细的表征。研究结果显示:固体酸中的不饱和三价铁离子具有路易斯酸性,磺酸基具有布朗斯特酸性,炭化温度800℃下制备的固体酸(800-ACN-Fe-SO_(3)H)具有最强的酸性(酸度0.81 mmol/g)和最大的比表面积(85.7 m^(2)/g),催化性能最佳。800-ACN-Fe-SO_(3)H用量0.20 g时,在反应温度200℃,反应时间5 h的条件下,纤维二糖的转化率为99.6%,产物乙酰丙酸(LA)和乙酰丙酸甲酯(ML)产率分别为15.6%和62.1%。催化剂经过5次循环回收,纤维二糖的转化率为93.1%,LA和ML的总产率为51.1%,表明催化剂具有良好的重复使用性,此外还初步探索了纤维二糖醇解的反应机理。

生物质基硬碳储钠负极材料研究进展

钠离子电池因其具有优异的低温性能、成本优势以及较高的安全性,有望逐渐成为锂离子电池在低速两轮车和大规模储能领域的补充者,开发低成本、高可逆容量和优异循环稳定性的钠离子电池负极材料成为行业难点,生物质基硬碳因其原料来源丰富、成本低廉、更易获得、碳产率高、环境友好且含有多种元素等优势而备受关注,其低廉的价格和独特的微观结构在众多钠离子电池负极材料中展现出明显的优势和巨大的商业潜力.为了寻找和开发性能优异的生物质基硬碳材料,本文首先对钠离子在硬碳表面活性位点的吸附行为和进入石墨片层的过程顺序进行了分析,讨论了有争议的四种钠离子存储机制.深入分析了钠离子在硬碳中的储存机理,并基于此进一步讨论了不同生物质基前驱体硬碳的差异,并通过硬碳负极的微观结构提出钠离子电池负极的优化策略,对钠离子电池的发展具有一定的指导意义.

双碳目标下绿色制氢技术的进展

发展高能效、低成本、零碳排放的可再生能源电解水制氢技术是实现“碳中和”“碳达峰”的重要途径。随着可再生能源的价格持续下降,利用可再生能源来实现高效的电解水制氢正逐渐成为未来氢能的主流技术路线。围绕当前绿色制氢技术的研究进展,重点阐述电解水制氢、太阳能分解水制氢以及生物质制氢等“绿氢”技术的产氢机理、技术难题和发展现状,并对未来绿色制氢技术的应用前景和发展方向进行分析和讨论。

两步法制备蔗渣基碳纳米管

通过两步法制备蔗渣基碳纳米管(CNTs),首先利用微波热解蔗渣得到生物质热解气,再将热解气作为碳源通入负载Fe基催化剂的管式炉中制备CNTs,利用XRD、SEM、Raman光谱等方法表征CNTs的微观结构。实验结果表明,生物质热解气通过化学气相沉积制备CNTs是一种较好的方法,制备的CNTs管壁光滑完整,Raman光谱中D峰与G峰的强度比小于0.5,2D峰与G峰的强度比大于0.8,说明制备的CNTs石墨化程度较好、纯度高,为蔗渣废弃物资源化提供了新思路。