Lignocellulose is the most abundant renewable biomass resource on the earth and cellulose is one of the three components of lignocellulose and is important raw material for the production of bio-based materials, fuels and chemicals. However, the complex chemical structure of lignin limits the application of lignocellulose. Conventional physical, chemical and physical-chemical lignin degradation methods often require high temperature and high pressure conditions, resulting in high energy consumption, inhibitors and environmental pollution. The biocatalysis process mediated by microorganisms is usually carried out under mild conditions, which can reduce energy input and provide a more specific and effective choice for the utilization of lignin. The degradation of lignin by fungi, represented by white-rot fungi, presents the problems of long pretreatment cycle and poor adaptability to the environment. Bacterium becomes the future potential of lignin degradation, owing to its rapid proliferation, profound environmental adaptability and easy genetic manipulation. This review introduced the progress of microbial degradation of lignin on the base of chemical structure, and mainly analyzed the microorganisms (fungi and bacteria), degrading enzymes (peroxidase and laccase) as well as the degradation mechanism. Besides, the applications of microbial degraded lignin in lipids, bioplastics, vanillin and wastewater treatment were summarized and the future development was suggested.

This work focused with the assistance of the mechanism of pyrolysis carbonization of cellulose, lignin and hemicellulose were analysed by TG, TEM, Raman, XRD, and FT-IR based on the molecular restructuring behavior of three major components of cellulose, lignin and hemicellulose during pyrolysis. The results showed that hemicellulose was completely decomposed during pyrolysis; molecular rearrangement occurred during the pyrolysis of cellulose, forming crystallized areas in biomass char; lignin had a very complex cross-linked structure, melted during pyrolysis, forming amorphous carbon areas in biomass char. During the charring process, cellulose undergone mainly dehydration reactions when the temperature was lower than 200 ℃, and the temperature range of 200 to 400 ℃ was the main stage of pyrolysis; lignin was relatively structurally stable in the studied temperature range(200-500 ℃), with only partial structural transformation occurring while softening and melting.

The polymers based on dynamic borate bonds had certain self-healing ability and multiple responses to stimuli, and they could respond to biological signal changes by inducing topological recombination of physical/chemical structures in the materials. A variety of natural/non-natural polymer materials based on three different transesterification mechanisms of borate esters were reviewed in this paper, namely hydrolysis/re-esterification, transesterification between diol and borate and transesterification between borate and borate. It was a strategy to design a more stable tetrahedral borate structure through the synergistic effect of traditional covalent bond and borate dynamic covalent bond to solve the borate ester polymer short plate. Application potential of borate-based polymers in many fields was summarized, such as biomedicine, sensors and recyclable materials. The synergistic of borate ester bond and other dynamic bonds to prepare ideal polymer materials was mainly emphasized, such as hydrogels, organic gels, liquid crystal materials, recyclable nanomaterials, etc.

The biochars I, R, S and M were prepared at 300, 500 and 700℃ with the grasses of king grass, rice straw, bagasse and corn straw as raw materials, respectively. The effects of different pyrolysis temperatures on the structure and composition of biochar were studied. Results showed that with pyrolysis temperature increasing, the yield of the four kinds of biochars decreased, carbon content and ash content increased. The yields of I, R, S and M at 300℃ were 45.81%, 48.67%, 46.81% and 46.00%, and the yields at 700℃ were 33.95%, 35.47%, 25.42% and 31.23%. The ash contents and I, R, S and M at 700℃ increased by 54.39%, 65.44%, 95.54% and 71.85% compared those at 300℃. The C/N ratio of R, S, and M were increased with pyrolysis temperature increasing, but that of R was opposite. The pH values of the four biochars increased with pyrolysis temperature increasing. The pH values of I, R, S and M at 700℃ were 7.68, 9.87, 7.59 and 9.33. I and S was porosity and the number of pore increased with the increase of pyrolysis temperature. Both R and M formed a certain amount of flocs at 700℃. EDX analysis revealed that the elemental composition of Si was contained higher in R. Infrared spectroscopy showed that with the increase of pyrolysis temperature, the alkane groups, methyl groups (—CH₃) and methylene groups (—CH₃) of the four kinds of biochars gradually disappear. The biochar structure was dominated by aromatic compounds and oxygen functional groups, and the structure was more stable.

As a kind of polymer material with versatile product forms, polyurethane is widely used in many applications. Developing technologies that can use green and renewable raw materials as feedstock has become a research hotspot, as well as great significance to the polyurethane research in the future. Based on the relevant literatures of the last decade, this paper focuses on the basic methods and research progress for the synthesis of bio-based polyols and isocyanates from common renewable alternatives, such as vegetable oil(castor oil, soybean oil, tung oil, palm oil, etc.), lignocellulose, rosin, natural phenols(cardanol and tannin), sugars and other biomass resources. In addition, the research status of non-isocyanates was mentioned, and the unique advantages of these materials for the preparation of bio-polyurethane were listed. This article also comprehensively examines the future hurdles that hinder the utilization of these materials, and then the development prospects of bio-based polyurethane materials in different fields are outlooked.

The new low-energy consumption process of corn fuel ethanol developed by our team adopted low temperature liquefaction, synchronous saccharification and batch fermentation of concentrated mash, three-tower differential pressure distillation and molecular sieve dehydration process and waste heat recovery technology from various sections of the plant. At present, it has successfully applied to a number of fuel ethanol distillery. Taking the Heilongjiang Hongzhan Science and Technology Co., Ltd. 300 000-ton fuel ethanol project as an example, the technical characteristics, energy consumption and product quality were compared and analyzed between the new and the traditional process. The results showed that the steam consumption, process water and amount of circulating water of the new process were reduced by 10.26%, 28.09% and 11.11% compared with those of traditional process, respectively. The production of 1 ton fuel ethanol could save 49 kg standard coal; thus 14 700 tons of standard coal could be saved annually and the energy consumption cost of fuel ethanol could be saved by about 8 million Yuan. At the same time, the product qualities of fuel ethanol and corn distiller's grains (DDGS) were in line with the national standards, some indicators were higher than the national standards, such as the purity of ethanol could reach 99.9%, methanol content was as low as 0.01%, crude protein content was 26.1%, crude fat content was 10.5% and the crude fiber content was 8.7%.

Biorefinery is an excellent strategy to deal with the energy crisis and environmental pollution in the new age. Based on biorefinery, low-value biomass resources can be converted into various value-added products. Furfural is one value-added platform chemical from biomass resources, which has important applications in energy, medicine, chemical, and other fields. The industrial production of furfural has come out for nearly one century and is relatively mature nowadays. However, there are still some issues remain to be solved in the industrial production. In order to solve these problems, efforts have been paid on exploring new technologies and progresses. In this paper, the characteristics of furfural were introduced firstly, and the present situation and problems of furfural industrial production technology are summarized, including corrosion of equipment caused by acid catalysts, difficulty in catalyst recycling, water pollution and so on. Then, the research status and problems of furfural preparation by hydrolysis and pyrolysis and the characteristic of the microwave-assisted technology were carefully reviewed. Finally, the future development direction of furfural preparation technology was prospected.

Camellia oleifera Abel shell, as a by-product produced during the processing of Camellia oleifera Abel, was usually discarded or burned. The resource utilization of C. oleifera shell can not only improve its own added value, but also solve the environmental pollution problems caused by it. Based on the existing research, this paper introduced the main functional components of C. oleifera shell and the utilization of C. oleifera shell in material, fertilizer and energy. C. oleifera shell contained tannins, tea saponins, flavones and polysaccharides and other substances, which made C. oleifera shell an ideal raw material for antibacterial, antioxidant, antiviral and other applications. In terms of materialization, the activated carbon adsorbent of C. oleifera shell showed good adsorption effect, but the capacitance material prepared from C. oleifera shell was low in conductivity, and the mechanical properties of wood-based composites were poor. In the aspect of fertilizer, the organic fertilizer and culture medium prepared from C. oleifera shell could obviously improve the soil, improve the quality of fertilizer and promote the growth of seedlings. In terms of energy utilization, the high lignin, hemicellulose and cellulose content made C. oleifera shell have certain advantages in direct combustion power generation, marsh gas production by anaerobic fermentation, bioethanol and bio-oil preparation, but there are some problems such as chloride corrode boiler, lignin is difficult to degrade, low bioethanol yield, low bio-oil yield and so on. In addition, the future utilization direction of C. oleifera shell was prospected. In the aspect of preparing carbon material, the C. oleifera shell need targeted carbonization for capacitor material. In the aspect of wood-based composites, it need to improve the structure and mechanical property. In the aspect functional components utilization, it need to develop high value-added deep processing products and expand production scale. In the aspect of energy, it need to solve the integration problem of biomass conversion process.

Biomass-based carbon materials had the advantages of low cost, wide source, good electrical conductivity, and good electrochemical stability. Through heteroatom doping, the performance of biomass-based carbon materials was further improved. This paper summarized the methods of introducing heteroatoms into biomass-based carbon materials(in-situ doping and diffusion doping) and their respective advantages and disadvantages. The types of heteroatom doping(nitrogen doping, oxygen doping, phosphorus doping, sulfur doping, halogen doping, and multi-element co-doping) and the effects of heteroatom doping on the structure and properties of biomass-based carbon materials were briefly described. The applications of heteroatom doped carbon materials in energy storage, adsorption separation, and catalytic oxidation were reviewed, and the development direction of heteroatom-doped biomass-based carbon materials was also prospected.

Hydrogen-rich syngas production from biomass gasification is considered as one of the most promising hydrogen production methods because of its clean and renewable raw materials and the diversity of product application. Catalysts play an important role in controlling the composition of biomass gasification products and the pyrolysis of tar. In this paper, the methods of hydrogen production from fossil energy, water decomposition, and biomass were reviewed, and the advantages, limitations, and existing problems of hydrogen production from biomass gasification were also analyzed. And, the influence factors of biomass gasification(gasification agent, reaction temperature, and catalyst) and the kinds of catalyst and its characteristics which used for biomass gasification(nickel-based, dolomite and alkali, and alkaline earth metal catalysts) were emphatically introduced. The research status of biomass gasification for making hydrogen rich syngas and catalysts in China and abroad were analyzed, and the prospects of the development of catalytic gasification for making hydrogen-rich syngas were discussed. The problems to be solved and the research direction were proposed.

As a "green technology", the light curing technology which is not only energy-saving, environmental protection but also economical and efficient, has been applied in many fields. The use of natural renewable resources to produce photocurable resins is of great significance to the sustainable development of photocurable technology. As a kind of natural renewable resource, itaconic acid with unsaturated double bond and two carboxyl groups could replace acrylic acid, hexanedioic acid and other petrochemical resources to synthesize various UV light curable unsaturated resins. The synthetic properties of the resin were excellent. The progress of preparation of itaconic acid UV light curable resins was reviewed, including epoxy itaconic acid resin, itaconic acid polyester, itaconic acid polyester acrylate, itaconic acid polyurethane acrylate, etc. The UV light curable resins from itaconic acid would have important application value in the fields of coatings, biomedicine and 3D printing, which could provide a new approach for the high value utilization of biomass products.

Catalytic conversion is an important route for the utilization of the renewable biomass resources, and the construction of highly efficient catalysts is a crucial step for the catalytic conversion of biomass and its derivatives. The hydrogenation conversion of biomass derived carbonyl derivatives into alcohols or ester compounds is an important step during the catalytic conversion processes of biomass. Due to the mild reaction conditions of the transfer hydrogenation process, the heterogeneous transfer hydrogenation catalysts have broad applications in the conversion of biomass derived carbonyl compound platforms. The transition metal zirconium and hafnium are commonly used as active metals for the transfer hydrogenation reaction. This review summarized the preparation of the zirconium and hafnium based transfer hydrogenation catalysts and their applications in the hydrogenation conversion of biomass derived platforms. Firstly, the preparation of the zirconium and hafnium based transfer hydrogenation catalysts were briefly introduced. Then, zirconium oxide or hydroxide, zirconium/hafnium based catalyst with different ligand (hydroxyl, carboxylic acid, phosphonic acid, sulfonic acid, tungsten acid, amine, organic metal skeleton, zeolite molecular sieve) ligand, the double metal catalyst and the comparative analysis of their catalytic performance, cycle stability and structural mechanism were reviewed in detail, and the performances of these catalysts were compared. Finally, the future perspectives of the catalytic transfer hydrogenation of biomass and the construction of the catalysts were prospected.

With the continuous improvement of the concept of green synthesis, transition metal catalysts with high catalytic activity, stability and low price replacing strong oxidizers and precious metal catalysts to catalyze the oxidation of 5-hydroxymethyl furfural(HMF) to prepare fine chemicals gradually become the focus of the researchers. This article reviewed recent researches on the use of cheap transition metal-based catalysts to catalyze the oxidation of 5-hydroxymethylfurfural(HMF) to 2, 5-furandicarbaldehyde(FDCA). The latest research in this field was described, with emphasis on introducing. The application of manganese-based, copper-based, iron/cobalt-based, nickel-based and other catalytic systems, such as manganese-based metal oxide, CuCl₂ catalytic system, Fe₃O₄-CoO_x magnetic catalyst, etc, in the HMF oxidation reaction were discussed. In addition, on the basis of the introduction of the above-mentioned catalysts, the development prospects of cheap transition metal-based catalysts catalyzed by HMF oxidation to prepare FDCA were also prospected.

Fast pyrolysis is one of the most promising methods for the efficient conversion and utilization of biomass. However, the target product, known as bio-oil, is difficult to utilize directly due to its high oxygen content and complex components. Fast pyrolysis of biomass catalyzed by alkaline earth metal oxides is able to remove the oxygen of the pyrolysis products in the form of CO₂ and H₂O, thereby improving the bio-oil quality. This review summarized the reaction mechanism (ketonization, aldol condensation, ring opening and side-chain scission) involved in the catalytic pyrolysis of biomass with the typical alkaline earth metal oxides-based catalysts. Also, the effects of catalysts (CaO, MgO, alkaline earth metal-based zeolites and activated carbons), raw biomass, pyrolysis temperature, catalyst amount, residence time, catalytic fast pyrolysis method and catalyst deactivation on the yield and quality of bio-oil were discussed. Finally, the application of biomass catalytic pyrolysis for producing high-quality bio-oil was prospected, which was expected to provide a theoretical basis for the utilization of biomass resources.

For the efficient and clean utilization of biomass energy, a two-stage enriched air gasification system was designed to improve the gas quality. The obtained clean high calorific combustible gas was used in gas turbine for power generation. The influence of the oxygen percentage of enriched air and secondary gasification temperature on the gasification performance and gas turbine operating characteristic were analyzed based on the Aspen Plus simulation. The results confirmed the feasibility of application of biomass gasification gas in gas turbines. And it was found that increasing oxygen percentage could efficiently improve the combustible gas quality and the system power generation efficiency. The secondary gasification temperature in the two-stage gasification system could cause slight decrease of gasification efficiency and power generation efficiency. Thus the gasification temperatue should be controlled in a reasonable range.When the gasification temperature was high enough for complete ash melting and separation, lower temperature could be chosen for saving energy. The optimum oxygen percentage of enriched air for two-stage gasification system was 50%-60%. When the oxygen percentage was 60% and the gasification temperature was 1 200 ℃, the power generation efficiency(η_t) reached maximum(34%), and the lower calorific value of the combustible gas was 9.54 MJ/m³ and the two-stage gasification efficiency(η_CGE) was 78.65%.

Using natural and renewable plant oils as raw materials to prepare pressure-sensitive adhesives is an effective way to solve the current resource shortage and environmental problems of petroleum-based pressure-sensitive adhesives, it is also one of the hotspots in academic research and application development. The author reviewed the research progress of plant oil-based pressure-sensitive adhesives by domestic and foreign researchers in recent years. And the adhesives were classified according to the types of plant oil-based polymers (epoxy resin, acrylic resin, fatty acid derivatives, polyester and polyurethane, etc.), and the design ideas and modification methods of these research were emphatically summarized. On this basis, the development of new plant oil monomer structure and copolymerization with functional monomer were discussed, so as to provide a feasible theory and reference for the design and development of new bio-based pressure sensitive adhesive materials.

Eucommia ulmoides gum(EUG) is a kind of natural polymer material with good biocompatibility, excellent rubber-plastic duality, and good mechanical properties, which has attracted much attention in the field of novel biomaterials in recent years. However, the poor elasticity and miscibility at room temperature have greatly limited its application in the field of functional materials. Therefore, the physical or chemical modification of EUG for broadening its range of applications has become the research hotspot. Combining with the structural characteristics of EUG, the common modification methods, formation mechanism and material properties of EUG by physical and chemical modification were firstly summarized, such as changing the hardness and elasticity of EUG by blending with other materials or epoxidation modification, vulcanization modification, etc. Then, the latest applications of EUG in green tire and road construction, shape memory and self-healing materials, anti-vibration and sound absorption, medical materials, and biodegradable composite are introduced, respectively. Finally, we envision that the EUG will play an increasingly important role in polymer science in future.

Environment protection, energy saving, and high efficiency are the main research directions for thermal insulation materials in the future, and the development of thermal insulation materials based on biomass is the future trend. Biomass-based porous materials refer to the porous materials prepared from renewable biomass as the precursor, which have the wide raw materials and diverse preparation methods. They have excellent characteristics, such as high porosity, low density, light weight, and so on, which has great application potential in the field of thermal insulation. In this paper, the heat preservation mechanism of the porous materials was overviewed, and the research progress on the cellulose, starch, chitosan, plant protein porous material in recent years was reviewed. The surfactant foaming method, freeze-drying method, pore-forming agent method, mould hot pressing method, solvent exchange phase separation in the application of biomass-based porous material preparation were also highlighted. Finally, the existing problems of biomass-based porous insulation materials are analyzed, and the future research directions of porous insulation materials are also prospected.

In order to resolve the utilization of solid-phase product generated in the process of coal-fired coupling biomass circulating fluidized bed gasification power generation, the effect of gasification temperature on fuel gas components, carbon content, specific surface area, micromorphology and adsorption capacity of the solid-phase products was investigated in Xiangyang power plant 6# unit with rice husk as the raw material. The results showed that, CO and H₂ contents in the gas increased first and then decreased with the increase of gasification temperature. When the temperature was 775 ℃, CO and H₂ contents arrived the highest values of 18.79% and 7.83%. During 625-775 ℃, a high calorific value of fuel gas, as well as the carbon content of solid-phase product, could be obtained. At a lower gasification temperature, a well-developed pore structure, an increased number of pores, and a medium thickness of pore wall could form and the larger specific surface area of solid-phase products increased by decreasing of the temperature. There was a linear correlation between the iodine adsorption value and the specific surface area. At 625 ℃, the maximum specific surface area of solid-phase products could be reached(145.3 m²/g), as well as the maximum adsorption capacity of iodine of 265 mg/g. The solid products are promising in the fields with a high consumption of adsorption materials while a relatively low demand for adsorption capacity.

The catalytic characteristics of metal ions for glucose isomerization and dehydration were investigated with metal chloride as catalyst. The influences of metal ion category, content and temperature on reaction process were studied. The reaction kinetic model was applied to correlate experimental data to analyze catalytic characteristics quantitatively. The process of glucose to HMF was a tandem reaction, and the kinetic model based on this mechanism could simulate the reaction accurately. Ni²⁺, Cr³⁺ and Sn⁴⁺ possessed good catalytic activity for glucose conversion, among which the catalyst activity of Sn⁴⁺ was the highest, and that of Ni²⁺ was the lowest. The kinetic constant of side reaction of Sn⁴⁺ was about 20 times of that of Ni²⁺. For Ni²⁺, reaction rate of glucose isomerization and side reaction increased, yet the catalytic activity for fructose dehydration to HMF was negligible with the increasing of Ni²⁺ content. Increasing of Cr³⁺ could enhance reaction rate of glucose isomerization significantly, and almost had no effect on other reactions. With the increasing of Sn⁴⁺ content, reaction rate of all steps increased, yet the intensity of side reaction would decrease. The influence of temperature on reaction constants followed the Arrhenius model. Higher temperature was beneficial to the side reaction, fructose dehydration and glucose isomerization respectively, when Ni²⁺, Cr³⁺ and Sn⁴⁺ were used, respectively.

Biomass is important renewable resources, mainly containing cellulose, hemicellulose, and lignin. Hemicellulose is the second most abundant component in plant cell walls, and it can be hydrolyzed to prepare important chemicals and modified to prepare multifunctional materials. This article reviews the research progress of molecular simulation of biomass hemicellulose, including the molecular simulation study of the morphology of hemicellulose macromolecules and its binding mode to cellulose, and the molecular simulation research on the preparation of chemicals and materials from hemicellulose. It can be concluded that the interaction of hemicellulose with cellulose and lignin in the cell wall and its macromolecular morphology have significant influence on the extraction and utilization of cellulose, hemicellulose, and lignin. Molecular simulation is helpful to understand the process mechanism and has important theoretical guiding significance for the improvement of reaction efficiency. Finally, the development and application of molecular simulation in hemicellulose research are prospected. The blank areas of hemicellulose molecular simulation are pointed out, mainly including the production of bio-oil by hemicellulose liquefaction, xylose isomerization to produce xylulose, the binding interaction between hemicellulose and lignin, and other hemicellulose-based materials, which requires further exploration and research.

Biomass fuel has the characteristics of high moisture, volatile, alkali metal content and low calorific value, which makes it more suitable for fluidized bed combustion. However, the alkali metal and Cl elements volatilized in the combustion process will threaten the safe and economic operation of fluidized bed boiler at a certain temperature. For example, the volatilization of Cl element is easy to lead to the corrosion of heating surface. The corrosion types can be divided into gas phase corrosion, liquid phase corrosion and solid phase corrosion. The corrosion degree is mainly affected by fuel composition and temperature. Through literature reading, this paper expounded the mechanism of corrosion of biomass circulating fluidized bed boiler, pointed out the corrosion phenomenon of actual boiler and engineering countermeasures according to engineering practice, and summarized that the prevention of corrosion could mabe breakthroughs in biomass fuel pretreatment, increasing secondary air ducts near the dense phase zone of the furnace, changing the layout of the superheater heating surface, adding specific additives and selecting the material of the heating surface. The conclusions were expected to provide guidance for the high reliability operation of biomass circulating fluidized bed boiler.

Based on the composition characteristics, hazards and treatment methods of biomass tar, the mechanism of catalytic cracking of biomass tar and the research progress in recent years are briefly introduced, and the catalytic conversion mechanism of biomass charcoal (mainly involving cracking, The three reactions of reforming and condensation), the adsorption and reforming of biomass charcoal, and the catalytic conversion process, the catalytic performance of biomass charcoal is affected by factors such as raw materials, cracking temperature, heating rate and residence time. By analyzing the performance changes of biomass charcoal after modification, it is found that the addition of metal promoters or structural modification of biomass charcoal has the potential for high-efficiency catalytic cracking of tar, which provides a direction for further research and development of low-cost composite catalysts.

Conversion of biomass into high value-added chemicals was an effective way to solve the current problems of fossil energy depletion and global warming. 5-Hydroxymethylfurfural(HMF) was considered as one of the most important platform compounds, which could be used to prepare many high value organic compounds through oxidation, hydrogenation, and ring-opening reactions. Among its derivatives, 2, 5-furandicarboxylic acid(FDCA) could be regarded as the most promising chemical, which could replace the widely used petroleum-based polyester terephthalic acid(PTA) to synthesize biodegradable polyester polyethylene furanoate(PEF). This article systematically reviewed the new processes for preparing FDCA from HMF through electrocatalytic oxidation, photocatalytic oxidation, and biocatalysis. These catalytic methods were different from traditional pyrolysis catalytic methods, which did not requiring high temperature and pressure as well as harmful solvents and expensive catalysts, and had the characteristics of high efficiency, greenness, and sustainability. However, there were still some problems, such as electrocatalysis needed special and stable electrolytes and high requirements for instruments and equipment; photocatalysis had the problems of high cost and low energy conversion rate; biocatalysis had long preparation cycles and the inhibited intermediates. By analyzing the results obtained by these methods and the existing problems, it provided feasible ideas for the efficient catalytic conversion of FDCA in the future.

In recent years, the application field of superhydrophobic materials has become more and more extensive, and the requirements on mechanical strength, wear resistance, light transmissibility, reuse and other properties of super hydrophobic materials have become higher and higher, and the requirements on green environmental protection of raw materials have been increasing day by day. Biomass materials have many kinds and large volume, which occupy the do minant position of renewable resources. Cellulose, as the downstream fine products of biomass materials, has entered the field of vision of researchers with its advantages of green environmental protection, large reserves and flexible application. This paper briefly indicates the development history, characteristic, and application of superhydrophobic materials and cellulose, the application of superhydrophobic modification methods such as hydrothermal method, chemical deposition method, atom transfer radical polymerization and sol-gel method (cellulose/SiO₂ super-hydrophobic materials and cellulose aerogel) in the preparation of cellulose based superhydrophobic materials was emphatically analyzed. Finally, the future development of cellulosic superhydrophobic materials was prospected.

Corn straw was used as raw material for aerobic biological pretreatment by a complex bacterial system and then inoculated with anaerobic sludge for anaerobic fermentation. The influence of pretreatment time on anaerobic fermentation was investigated, and the changes in lignocellulose structure and content, key enzyme activities, microbial diversity and anaerobic acidification fermentation yield were determined. The results showed that with the extension of pretreatment time, the structure of corn straw was gradually destroyed, the activity of lignin peroxidase, the key enzyme for lignin degradation, gradually decreased, and the activities of xylanase and cellulase gradually increased and were up to 0.879 U/mg and 0.0257 U/mg. Actinomyces, Bacillus and Aspergillus were the dominant bacterium groups in the aerobic biological pretreatment of straw. The best acid production from anaerobic fermentation of corn straw was achieved by aerobic biological pretreatment for 2 d. The yield of ethanol and volatile fatty acids was 249.3 mg/g, 46.73% higher than that of untreated. The yield of ethanol and volatile fatty acids was 138.2 mg/g after 5 d of aerobic pretreatment, which was 18.66% lower than that of the untreated corn straw. The reason for the decrease of volatile fatty acids production from anaerobic fermentation due to extended aerobic pretreatment time was the excessive degradation of hemicellulose and cellulose. The pretreatment method of anaerobic fermentation of corn straw using aerobic biological pretreatment with complex microbial system as the purpose of energy and resource utilization should strictly control the pretreatment time to avoid the decrease of product yield caused by excessive degradation of cellulose and hemicellulose.

With the rapid development of automobiles and manufacturing, the demand for lubricant has also greatly increased, and a large amount of waste lubricant has also been produced. Based on the current pollution status of waste lubricant, this article introduced its deterioration process, pollutant composition, and commonly regeneration processes (flocculation, distillation, extraction, hydrotreating, adsorption, etc.). The article introduced the adsorbents, such as clay, activated carbon, fly ash, natural polymer adsorbents and so on and new technologies (electrostatic adsorption) in detail. The overseas and domestic research status of adsorption regeneration were summarized and the merits and demerits of the adsorbents and adsorption technologies were summarized. Therefore, the problems and development trends of waste lubricant absorption regeneration in the future were proposed.

Before determining the specific surface area and pore volume of woody activated carbon, the activated carbon was pre-treated with degassing, and the effect of pre-treatment conditions(desorption temperature and desorption time) on the specific surface area and pore volume of activated carbon was investigated. The obtained results were compared with those measured under the recommended conditions of the instrument. The results showed that the desorption temperature and time had little influence on the specific surface area and pore volume of physical activated carbon. It was owing to the preparation temperature of physical activated carbon was high few functional groups, the structure was mainly microporous, the adsorption type was mainly physical adsorption, and the adsorption and desorption speeds were fast. The optimum pretreatment condition of physical activated carbon was desorbed at a temperature of 150 ℃ for 3 hours. Compared with the pretreatment conditions of 350 ℃ and 24 hours recommended in the instruction manual of ASAP 2460, pretreatment time was significantly shortened, the power consumption was reduced, and the detection efficiency was improved. The degassing temperature and time had a great influence on the specific surface area and micro-pore of chemical wood activated carbon, and the suitable pretreatment condition was 300 ℃ for 12 h. The main reason was that the preparation temperature of activated carbon by phosphoric acid method was relatively low, and there were many heteroatoms and the surface chemical groups. Physical and chemical adsorption were easy to occur simultaneously, which required higher temperature and longer time for degassing. When the degassing temperature was too high, the adsorbate in the pores would be carbonized to form carbonaceous particles that blocked the pores. At the same time, part of the physical adsorption would be converted into chemical adsorption at a higher activation energy, which would reduce the analysis results.