Removal of humic acid from water using adsorption coupled with electrochemical regeneration

A novel and economic waste water treatment technology comprised of adsorption coupled with electrochemical regeneration was introduced at the University of Manchester in 2006. An electrically conducting adsorbent material called Nyex? 1000 (Graphite intercalation based material) was developed for the said purpose. This adsorbent material delivered significantly lower adsorption capacity for the removal of a number of organic pollutants. With the aim to expand the scope of newly developed adsorbent material called Nyex? 2000, we studied the adsorption of humic acid followed by electrochemical regeneration. Nyex? 2000 is a highly electrically conducting material with an adsorption capacity almost twice that of Nyex? 1000 (intercalation based graphite compound) for humic acid. The adsorption of humic acid onto both Nyex? adsorbents was found to be fast enough keeping almost the same kinetics with approximately 50% of the adsorption capacity being achieved within the first twenty minutes. The parameters affecting the regeneration efficiency, including the treatment time, charge passed and current density, were investigated. The regeneration efficiency at around 100% for Nyex? 1000 & 2000 adsorbents saturated with humic acid was obtained using the charge passed of 8 and 22 Cg^?1 at a current density of 7mA cm^?2 during a treatment time of 30minutes, respectively.     

Electrochemical regeneration of a carbon-based adsorbent loaded with crystal violet dye

The removal of colour from a crystal violet dye solution using a non-porous, electrically conducting carbon-based adsorbent was systematically investigated under different operating conditions. Whilst the adsorptive process was very quick (up to 88% of equilibrium capacity could be achieved within 2 min), the adsorptive capacity of the adsorbent was very low (2 mg g⁻¹) compared with activated carbons. This was due to its low surface area. The conductivity of the adsorbent/electrolyte mixture within the anodic compartment of the electrochemical cell was found to be over 13 times greater with the new adsorbent compared with powdered activated carbon. One hundred percent could be achieved in a simple divided electrochemical cell using treatment times as low as 10 min by passing a charge of 25 C g⁻¹ at a current density of 20 mA cm⁻². The efficiency of electrochemical regeneration depends on a range of variables including charge passed, current density, treatment time, electrolyte type and concentration and the adsorbent bed thickness. Multiple adsorption and regeneration cycles indicate that there is little or no loss in adsorbent capacity on regeneration.     

Pre-treatment of adsorbents for waste water treatment using adsorption coupled-with electrochemical regeneration

With the aim to address waste water treatment problems, a novel and economic water treatment technology was introduced at the University of Manchester. It comprised of a unique combination of adsorption and electrochemical regeneration in a single unit. This process successfully eliminated a number of organic pollutants by using an electrically conducting adsorbent material called Nyex? which was a modified form of synthetic graphite. To expand the scope of other graphite types in waste water treatment applications, natural vein and recycled vein graphite materials were selected for electrochemical surface treatment (pre-treatment) in order to evaluate their adsorptive and electrical properties. New graphite based adsorbents were developed and characterized using a laser diffraction particle size analyser, BET surface area, SEM analysis, X-ray (EDS) elemental analysis, X-ray powder diffraction, Boehm surface titration, Zeta potential electrical bed conductivity and bulk density measurements. Boehm surface titration and EDS (X-ray) elemental analysis showed a significant increase in oxygen containing surface functional groups. Although, no significant improvement in bed electrical conductivity was found to occur after electrochemical surface treatment, however, natural vein and recycled vein graphite materials presented highest bed electrical conductivity amongst competing graphite materials. Aqueous solution of acid violet 17 as a standard pollutant was used to evaluate the comparative performance of these adsorbents. The investigations revealed that electrochemical surface treatment contributed to an increase in the adsorption capacity by a factor of two only for natural vein graphite. Un-treated recycled vein graphite adsorbent delivered the same adsorptive capacity (3.0 mg g^?1) to that of electrochemically treated natural vein graphite. The electrochemical regeneration efficiency at around 100% was obtained using a treatment time of 60 and 30 min, current density of 14 mA cm^?2, charge passed of 36 and 18 C g^?1 for synthetic graphite, natural and recycled vein graphite materials respectively. Relatively a small consumption of electrical energy, 24 J g^?1 for regenerating natural vein graphite adsorbent versus 36 J g^?1 for synthetic graphite adsorbent, was found to be required for destruction/oxidation of adsorbed acid violet 17. Multiple adsorption/regeneration cycles presented no loss in adsorptive capacity over 5 adsorption/regeneration cycles. The use of natural and recycled vein graphite adsorbents offered some advantages over graphite intercalation based adsorbents with reduced electrical energy consumption during regeneration and simpler separation of particulate adsorbent.     

Wastewater treatment by adsorption with electrochemical regeneration using graphite-based adsorbents

An innovative technology for wastewater treatment using adsorption and electrochemical regeneration has been developed at the University of Manchester. The process uses a low capacity graphitic adsorbent material (a graphite intercalation compound, Nyex^TM 1000) which can be regenerated electrochemically. In this study, we investigate the characteristics of a new, partially porous adsorbent material, Nyex^TM 2000 which offers increased surface area in comparison with Nyex^TM 1000. Nyex^TM 2000 was found to have an adsorption capacity of almost three times that of Nyex^TM 1000. The electrical conductivity of a Nyex^TM 2000 was found to be double that of Nyex^TM 1000, enabling improvements in the electrochemical regeneration characteristics. The removal of an anionic azo dye, acid violet 17, from aqueous solution using Nyex^TM 1000 and 2000 was investigated under various operating conditions. The adsorption of acid violet 17 on Nyex^TM 2000 was found to be comparatively fast with 75 % of the equilibrium capacity being achieved within 5 min. The parameters affecting the regeneration efficiency including the charge passed, current density, treatment time, adsorbent bed thickness, and pH were investigated. An electrochemical regeneration efficiency of around 100 % was achieved for a fully loaded Nyex^TM 2000 in a sequential batch electrochemical cell with a regeneration time of 60 min and a charge passed of 100 C g⁻¹ at a current density of 14 mA cm⁻². The charge required for electrochemical regeneration was found to be approximately equal to theoretical charge required for complete oxidation of the adsorbed acid violet 17, making process design relatively simple. Nyex^TM 2000 was found to be an economic adsorbent with relatively small electrical energy consumption required (31 J mg⁻¹ of acid violet 17 treated, compared to 52 J mg⁻¹ of acid violet 17 for Nyex^TM 1000). Multiple adsorption/regeneration cycles presented no loss in adsorptive capacity and material loses over five adsorption/regeneration cycles.     

Synthesis of electrically conducting composite adsorbents for wastewater treatment using adsorption & electrochemical regeneration

Electrically conducting adsorbent materials called Nyex™ 1000 & 2000 have already been reported with comparatively low adsorption capacity for various organic, biologically non-degradable and toxic compounds. Two composite adsorbents called CA₁ & CA₂ were synthesized using synthetic graphite-carbon black and expanded graphite-carbon black respectively. The aim of developing the new adsorbents was to increase the adsorption capacity along with good electrical properties. The developed adsorbents were characterized using N₂ adsorption for specific surface area, Boehm surface titration for surface chemistry, bed electrical conductivity, laser size analyzer for average particle size, and scanning electron microscope (SEM) for particle morphology and shape. Then both the composite adsorbents were tested for the adsorption of acid violet 17 followed by an electrochemical regeneration. The adsorption study revealed that both the adsorbents had almost similar kinetic behavior with a significant increase in adsorption capacity for acid violet 17 (300 & 26 mg g⁻¹ respectively) when compared with the adsorption capacity of previously developed electrically conducting materials called Nyex™ 1000 & 2000 (3.5 and 9 mg g⁻¹ respectively). The composite adsorbent CA₂ was successfully electrochemically regenerated by passing an electric charge of 138 C g⁻¹ at a current density of 14 mA cm⁻² for a treatment time of 60 min, whereas, the composite adsorbent CA₁ could not be regenerated successfully. The regeneration efficiencies of CA₂ were obtained at around 120% during five adsorption–regeneration cycles. The amount of actual charge passed of 138 C g⁻¹ for achieving 100% regeneration efficiency was found to be similar with stoichiometrically calculated amount of charge. The amount of electrical energy required to oxidize each mg of adsorbed acid violet onto CA₂ (24 J mg⁻¹) was found to be significantly lower to that of Nyex™ 1000 & 2000 adsorbents (52 J mg⁻¹ & 32 J mg⁻¹ respectively).     

Modeling of Adsorptive Filtration of a Leather Dye in a Fixed Bed Column

Abstract

Activated carbons offer an efficient option for the removal of organic and inorganic contaminants from water. However, due to its high costs and difficulty in the regeneration, other low cost adsorbents have been used. In this work, the adsorption capacity of an adsorbent carbon with high iron oxides concentration was compared with that of a commercial activated carbon in the removal of a leather dye from an aqueous solution. The adsorbents were characterized using SEM/EDAX analysis and BET surface area. The capacity of adsorption of the adsorbents was evaluated through the static method at 25°C. The results showed that the color removal was due to the adsorption and precipitation of the dye on the surface of the solids. The adsorption equilibrium was described according to the linear model for the adsorbent carbon and the equilibrium constant was 0.02 L g^?1. The equilibrium of adsorption on activated carbon exhibited a behavior typical of the Langmuir isotherm and the monolayer coverage was 24.33 mg g^?1. A mathematical model was proposed to describe the dynamics of the color removal using a fixed bed considering that the color removal is due to the adsorption and the precipitation of the dye on the adsorbent.     

A poly(2-hydroxyethyl methacrylate)-based immobilized metal affinity chromatography adsorbent for protein purification

Poly(HEMA) microbeads were prepared by suspension polymerization of 2-hydorxyethylmethacrylate and ethyleneglycoldimethacrylate (EGDMA). The water content, ligand density, and selectivity for poly(His)-tagged d-hydantoinase of the poly(HEMA)-based adsorbents were affected by the concentration of EDGMA used during polymerization. The Ni(II)-loaded poly(HEMA) adsorbent exhibited an adsorption capacity of 1.0 mg/g for poly(His)-tagged d-hydantoinase under optimal conditions with buffer containing 100-300 mM NaCl at pH 6.0. One-step purification protocol with the adsorbent gave a purity of at least 92%. The adsorption capacity of adsorbent declined by 54% after 7 cycles, due to the leaching of Ni(II) from the adsorbent. However, upon regeneration the adsorption capacity can be restored. Given the ease of preparation and the chemical and microbial resistance, the poly(HEMA)-based IMAC adsorbent could be a promising substitute for the polysaccharide-based IMAC adsorbents.     

多孔材料对柴油脱色及脱碱性氮性能的对比研究

以焦化柴油和催化柴油加氢精制混合柴油作为原料,在一定条件下,考察了不同类型固体吸附剂对柴油脱色脱碱性氮的效果。静态实验结果表明,活性炭吸附剂的脱色效果最好,ASTM D1500色度达到0.2;硅酸铝吸附剂的脱碱性氮效果最好,脱除率达到90%。动态实验结果表明,活性炭吸附剂的胶质饱和吸附量最高,达到5.58%,但碱性氮饱和吸附量仅有0.45%。硅酸铝吸附剂的脱碱性氮效果最好,碱性氮吸附容量为0.91%,碱性氮饱和吸附量达到1.24%。与新鲜剂相比,采用高温焙烧再生,活性炭吸附剂能够完全恢复脱色脱胶质能力;采用极性溶剂再生,硅酸铝吸附剂能够完全恢复脱碱性氮能力。     

Fabrication of magnetic β-CD/chitosan nanocomposite as an efficient and recyclable dye adsorbent

ABSTRACT

In this work, novel magnetic nanocomposite adsorbents were prepared by crosslinking β-cyclodextrin (β-CD) onto chitosan backbones by using epichlorohydrin as a crosslinker and in the presence of Fe₃O₄ nanoparticles. The composition of β-CD-chitosan nanocomposites was characterized via FTIR, XRD, TEM, SEM, and VSM. Then, the as-prepared nanocomposites were treated for elimination of methyl orange (MO). The results indicated that the adsorption of MO exhibited a maximum adsorption capacity of 314 mg g^?1 at 25°C. Moreover, the rates and isotherm data of adsorption matched excellent at different MO concentrations (10, 60, and 120 mg/L) using second-order and Langmuir models with the regression coefficient (R²) of 0.9993 and 9990, respectively. Besides, the thermodynamic data confirmed MO adsorption as an endothermic process. The adsorbent was also confirmed as good materials for re-use and maintained 88% of its initial adsorption capacity for MO after the fifth regeneration cycles. In conclusion, the synthesized magnetic nanocomposites can be applied as cost-effective dye adsorbents with high regeneration efficiency.     

Arsenic adsorption using copper (II) oxide nanoparticles

Arsenic poisoning is a major problem in today's life. To reduce its concentration in drinking water, different metal based compounds were explored as arsenic adsorbents. In the present study, copper (II) oxide nanoparticles were prepared by thermal refluxing technique and used as an adsorbent for arsenic removal from water. Characterization of the adsorbent using TEM, BET, XRD and FTIR implied that the prepared adsorbent was in nano size and had excellent adsorption behavior with surface area of 52.11 m²/g. Systematic adsorption experiments were carried out with different process parameters such as contact time, adsorbent mass, pH, temperature and stirring speed and found that copper (II) oxide had very good efficiency towards arsenic adsorption. Thermodynamic parameters and adsorption kinetics were studied in detailed to know the nature and mechanism of adsorption. Results showed that the adsorption process followed pseudo second order kinetic and endothermic behavior. Adsorption equilibrium was studied with Langmuir and Freundlich isotherm models. The adsorption process followed Langmuir isotherm with an adsorption capacity of 1086.2 μg/g. A regeneration study was proposed in order to reuse the adsorbent for better economy of the process. Finally, a process design calculation is reported to know the amount of adsorbent required for efficient removal of arsenic from aqueous medium.     

不同方法制备的镍基非加氢脱硫吸附剂的脱硫效果

针对不同方法制备的镍基非加氢脱硫吸附剂及改性前后的吸附性能进行评价。在常压下,以100×10-6噻吩的苯溶液为模型原料油,氧化镍作为吸附剂的活性组分,评价各吸附剂的脱硫性能,分析等温吸附曲线,改性前后、再生前后脱硫性能的变化规律。结果表明,不同方法制备的吸附剂吸附效果大不相同。沉淀法制备的吸附剂表面活性组分分布均匀,半峰宽较小,结晶度高,吸附硫容大,操作简便。助剂氧化锌的添加起到较好的助催化效果,且能增强活性组分与载体之间的相互作用。沉淀法制备的吸附剂的再生性能优异,能够很好的重复利用。     

空气中直接捕集CO2技术研究进展

减少碳排放并推动碳中和是应对气候变化、促进经济社会绿色转型的重要途径之一,碳中和技术已成为工业界和学术界的关注焦点。目前碳捕集与封存主要对工业固定源排放的CO₂进行处置捕集,而对占CO₂总排放近50%的分布源CO₂关注度不高。直接空气捕集(direct air capture,DAC)技术不仅可对数以百万计的小型化石燃料燃烧装置以及数以亿计的交通工具等分布源排放的CO₂进行捕集处理,还可有效降低大气中CO₂浓度。介绍了DAC的发展历史、研究现状以及发展趋势,综述了已有DAC技术的工艺流程以及反应装置,对DAC现行工艺中涉及的空气捕捉模块、吸收剂或吸附剂再生模块、CO₂储存模块进行了叙述,对比了几种工艺的优缺点以及吸附剂类型和再生方式,指出DAC技术发展的关键在于研发高效低成本的吸收/吸附材料和设备。分析了DAC吸收/吸附材料的作用原理以及吸附效果,碱性溶液原料成本相对低廉,但再生过程中能耗较高。分子筛及金属有机框架吸附剂虽然再生能耗较低,但对空气中CO₂的吸附容量和吸附选择性表现一般。胺类吸附剂具有较好的吸附能力,由于其再生温度较低,可使用工业废热或少量热能为系统供能;使用胺类吸附剂时吸附和解吸在一个单元中逐步发生,具有更高的效率和操作时间,有望降低DAC系统成本。对比了DAC与其他碳捕集技术的成本并进行了技术经济性分析,DAC成本主要包含运营和维护成本(N_Q&M)、吸附剂材料成本(N_S)和工厂设备的净成本(N_bop);指出目前限制DAC工业化应用的主要因素之一在于吸收/吸附材料和相关工艺成本过高,随着阴离子交换树脂等新型吸附剂的出现和工艺的发展,DAC成本逐年下降。全面探究吸收/吸附材料稳定性、动力学、吸附容量、选择性、再生能量损失等综合性能,研发利于快速装载和卸载吸附剂的相关装置,开发成本低廉的工艺系统是目前DAC领域的发展方向和迫切需求。DAC技术将为减少全球碳排放、实现碳中和提供重要技术支撑。     

Attapulgite/carbon composites as a recyclable adsorbent for antibiotics removal

We evaluated the adsorption performance of attapulgite/carbon (APT/C) composite as reusable adsorbents for antibiotics. APT/C composite was first synthesized by one-step calcination based on the spent bleaching earth after bleaching of vegetable oil, and followed by a thermal regeneration after adsorption of antibiotic at different temperatures. Antibiotics adsorption results revealed that APT/C composites prepared at 300 °C exhibited high adsorption capacity and fast equilibrium. Thermal regeneration proved to be an efficient methodology for recycling the spent antibiotic-loaded APT/C composites. After the ten-time continuous adsorption-calcination process, the removal ratios of the recycled adsorbents still retained around 67.3% and 62.9% for chlortetracycline and tetracycline, respectively. The conjugation of the adsorption and regeneration results suggested that combining the advantages of APT and carbon species provided a feasible strategy to fabricate a promising adsorbent with the desirable adsorption and regeneration properties for removal of antibiotics in the future.     

Removal of methylene blue from coloured effluents by adsorption onto SBA‐15

Adsorption has been proven to be the most efficient method for quickly lowering the concentration of dissolved dyes in an effluent. In this regard, activated carbon is the most widely used adsorbent for removal of dyes from aqueous solution. However, the high cost of production and regeneration make it uneconomical. Therefore, inorganic adsorbents (e.g. zeolites) with high surface areas have been used as alternatives to carbon adsorbents. Microporous zeolites ZSM‐5, NH₄‐Beta, MCM‐22 and mesoporous materials MCM‐41 have been investigated for the removal of dyes from aqueous solutions and they show effective adsorption performance. SBA‐15 possesses a larger pore size and pore wall thickness than MCM‐41. As a result, SBA‐15 has greater potential for the adsorption of methylene blue with larger molecule size and higher hydrothermal stability than the M41S family. SBA‐15 is an excellent adsorbent for methylene blue (MB), exhibiting 280 mg g^?1 adsorption capacity and about 100% fading rate for MB. The adsorptive process is so fast that adsorption equilibrium is achieved in 5 min. In addition, SBA‐15 can be effectively recovered by calcination and reused 10 times without significant loss in removal of MB from aqueous solution. The efficient adsorption of MB molecules onto SBA‐15 was ascribed to MB adsorbed into the pore channels of SBA‐15, which was confirmed by nitrogen physisorption analysis of the adsorbent before and after adsorption. The long reuse life of the adsorbent suggests a high potential for application in industry. Copyright © 2010 Society of Chemical Industry     

Synthesis of bifunctional polymeric adsorbent and its application in purification of stevia glycosides

Polymeric adsorbents with both functions of adsorption and decolorization were synthesized by introducing quaternary ammonium groups (e.g. –N⁺(CH₃)₃ groups) into conventional resinic adsorbent used to adsorb stevia glycosides in production. The relation between the adsorption capacity of the bifunctional adsorbents for stevia glycosides and the structure of adsorbents, and that between the decolorization efficiency and the structure were investigated. The results revealed that the adsorption capacity for stevia glycosides decreased somewhat as the increase of the content of quaternary ammonium groups in the adsorbent, while the decolorization efficiency increased. Adsorbents containing about 0.6–0.8 mmol/g of –N⁺(CH₃)₃ groups showed both high adsorption capacity and high decolorization efficiency, and showed adsorptive selectivity for the small-sized components of stevia glycosides. Mechanism of adsorption and decolorization was also studied, and revealed that adsorption of stevia glycosides was based on hydrophobic interactions, but decolorization was based on both ion exchange and hydrophobic interactions. Introduction of –N⁺(CH₃)₃ groups into polymeric adsorbent also changed the adsorption selectivity for various stevia glycosides, and thus the bifunctional adsorbent could be used to prepare stevia glycosides with high content of rebaudioside A.     

Novel type of alginate gel‐based adsorbents for heavy metal removal

Various alginate gel‐based adsorbents were investigated for the removal of heavy metals: alginate beads, alginate capsules, and alginate gel‐coated adsorbent. Of these, alginate capsules showed the greatest Pb²⁺ uptake capacity of 1560 mg g^?1 of dry sodium alginate, and the alginate gel‐coated adsorbent, prepared simply by forming a thin alginate film on an inert matrix, achieved rapid adsorption equilibrium within 10 min. Adsorbed metals were readily removed from the alginate gel‐based adsorbents using eluents such as HNO₃ and could be reused for up to 10 adsorption–desorption cycles without marked loss of metal uptake capacity. Alginate gel‐coated adsorbents could be prepared in a dried state and have great application potential for the removal of heavy metals from contaminated water. Copyright © 2004 Society of Chemical Industry     

车用燃料油固体脱硫吸附剂的研究进展

吸附脱硫的优势是投资成本低、操作条件温和,其技术关键在于研发吸附硫容量大、选择性高和再生性能好的固体吸附剂。本文综述了车用燃料油固体脱硫吸附剂的研究进展,包括常规的分子筛、活性炭、金属氧化物吸附剂以及一种新型金属-有机骨架（MOFs）材料脱硫吸附剂。从吸附机理、制备方法、脱硫效果等方面分析了上述吸附剂的优缺点和改进方向。提出今后的固体脱硫吸附剂可从吸附机理出发在分子尺度上设计和组装新材料的观点。     

Synthesis and adsorption performance of fly ash/steel slag-based geopolymer for removal of Cu (II) and methylene blue

In order to realize the value-added resource utilization of solid waste, geopolymer particle adsorbents were prepared at low temperatures using silica-aluminum-rich fly ash and steel slag powders as raw materials. In order to investigate the mechanism of their adsorption of dyes and heavy metal ions from wastewater, the effects of steel slag/fly ash ratio, adsorbent dosage, initial concentration of methylene blue (MB) and Cu²⁺ solution, adsorption time and temperature on the adsorption performance of the fly ash/steel slag-based geopolymer adsorbents were investigated, systematically. Results presented that the adsorption capacities of MB and Cu²⁺ were 33.30 and 24.15 mg/g, and the removal efficiencies were 99.90% and 96.59% with the dosages of 3 and 4 g/L geopolymer adsorbents (steel slag/fly ash ratio of 20 wt.%), respectively. The adsorption processes of MB and Cu²⁺ on the adsorbents were in accordance with the proposed pseudo-second-order and Langmuir isotherm models, which mainly included physical and chemical adsorption mechanisms. The adsorption was a spontaneous endothermic process. The fly ash/steel slag-based geopolymer had good removal ability for dyes and heavy metal ions, and it could maintain good adsorption performance after three cycles of regeneration. It had potential application in wastewater treatment.     

Preparation of hierarchical magnesium silicate with excellent adsorption capacity

Magnesium silicate (MS) is a widely used adsorbent, and much work has been done to control the surface morphology of MS to improve its adsorption capacity. In this work, hierarchical MS was prepared by combining hydrothermal process with freeze drying technique for potential application in adsorption. Firstly, the MS hydrogel was prepared by hydrothermal process, followed by replacement of water in hydrogel by tert-butyl alcohol. Finally, the MS was obtained by freeze drying. The prepared MS exhibited a rough and porous hierarchical structure having BET specific surface area and total pore volume of 530?m²/g and 0.90?cm³/g, respectively. MS was further used for methylene blue (MB) adsorption in aqueous solution and the adsorption data exhibited good correlation with the Langmuir adsorption isotherm model. The maximum adsorption capacity for MB was found to be 526?mg/g, far higher than the conventional adsorbents that popularly reported in literature. In conclusion, this work provides a novel route to prepare adsorbents with high adsorption performance.     

低温吸湿复合吸附剂的制备及吸湿性能

针对冷库结霜严重制约其经济性的问题,化学固体吸附除湿防霜技术逐渐得到重视。本文将对水吸附能力较强的金属卤化物与容易定型且传热传质性能较好的分子筛相结合,制成复合吸附剂,建立了低温情况下吸附材料的吸湿性能测试系统,并进行了大量测试,给出了多种材料在-5℃、-10℃、-15℃下的吸湿量及吸湿速率变化,实验结果表明复合吸附剂的吸附性能与单纯的分子筛相比有了明显的改善,13X型分子筛浸渍浓度20%的Na Br溶液所得试样吸湿量和吸湿速率性能优越,复合过程中损失较少,成本低,可作为复合吸附剂应用于冷库除湿系统中。