贝壳制备氨基葡萄糖盐酸盐影响因素的探讨

本文探讨了水解时间,质量配比、盐酸浓度、术解温度、甲壳素粒度、脱色时间及温度、浓缩结晶条件对GAH产率和质量的影响.实验表明:甲壳素水解制备氨基葡萄糖盐酸盐的水解时间控削在3.5 h、甲壳素与盐酸的质量比为1:6,盐酸浓度为36%、水解温度为90℃、甲壳素粒度为25目、脱色时间为35min、脱色温度在65～70℃、晶体与母液比在1:1左右时,产品的质量和产率最好.     

黄连中盐酸小檗碱的提取工艺教学实验改进

采用解吸-内部沸腾两步法改进大学专业实验黄连中盐酸小檗碱的提取工艺,得到最佳提取工艺如下:解吸剂浓度为40%乙醇、解吸剂固液比1:2、热提第一次时间1 min、第二次时间5 min、热提剂固液比1:40。并与传统醇提法相比,提取时间短、乙醇消耗少和浸膏有效成分含量高,有效的提高了实验效率和经济性。     

环保型纤维素海绵高粘度粘胶液生产工艺研究

纤维素海绵的产品性能主要受粘胶液粘度的影响。文章研究了高粘度的粘胶液的制备条件,通过对纤维素浆粕聚合度、碱液浓度、反应温度和固液比的考察,确定了最优的工艺条件,用500 DP纤维素浆粕在固液比1∶3.8、碱量15 wt%、温度5℃的条件下,生产出的粘结液粘度最大在152 cps。     

从粉煤灰中提铝的试验研究

文章对粉煤灰焙烧——酸浸过程进行了研究,考察了焙烧、酸浸对提取铝的影响。试验结果表明：焙烧条件为：时间2h,焙烧温度850℃,粉煤灰与ZP的质量比为5∶1;浸出条件为：反应温度90℃,浸出时间2h,盐酸浓度5ml/l,液固比5ml/g的条件下,铝提取率达到93.12%。     

淫羊藿总黄酮的提取工艺优化

目的:探讨淫羊藿总黄酮和多糖的提取工艺优化条件。方法:以淫羊藿中含有的总黄酮含量为主要的评价指标,分别考察浸提温度、浸提时间、固液比和乙醇浓度四个因素对总黄酮提取量的影响,采用正交试验优化淫羊藿中总黄酮的提取工艺。结果:经过研究后发现淫羊藿中总黄酮的最佳提取条件为60%乙醇,固液比为l:10条件下80℃进行回流提取2次,每次1h。结论:经过优化后的总黄酮提取工艺简单、方便、提取率高,值得推广使用。     

造纸高浓磨浆工艺条件的优化

以甘蔗浆粕为原料,水溶性蛋白质的得率为指标,采用正交试验对造纸高浓度磨浆工艺进行优化。通过优化,得到的最佳工艺条件为:固液比1:8,浸泡温度65℃,浸泡时间3h,碳酸氢钠浓度0.5%,水溶性蛋白质的得率为39.42%。实际应用结果表明,浆体质量和得率提升明显,能源消耗显著降低。     

槐米中芦丁的微波提取研究

目的：优化槐米中芦丁的提取工艺。方法：以芦丁提取率为评价指标,采用正交试验法对芦丁的提取工艺进行优选。结果：最佳的工艺条件为提取温度65℃,提取时间5min,固液比1：10,甲醇浓度90%。结论：优选出的工艺科学合理。     

响应面法在优化中药提取工艺中的应用

目的:探讨响应面法在优化中药提取工艺中的应用,方法:以灯芯草多糖的产率为衡量指标,在单因素的实验基础上,利用响应曲面法分别对水提法中的提取温度、提取时间、料液比3因素进行分析,从而优选最佳提取工艺。结果:水提法的最佳提取工艺条件为温度80℃、提取时150min、水料比20:1,此条件下,灯芯草多糖的提取率为1.431%。结论:水提法的最佳提取工艺为:温度80℃、提取时150min、水料比20:1,此条件下,灯芯草多糖的提取率为1.431%,可以在运用中推广。     

酶解法制取蚕蛹多肽

以蚕蛹为原料,经脱脂后,采用碱法提取蚕蛹蛋白,以双酶水解的方法制取可溶性蚕蛹多肽,最佳制取条件为固液比1:10,水解温度45℃,酶用量3%(木瓜蛋白酶:胰蛋白酶=1:1),水解时间6h,在此条件下制备的蚕蛹多肽得率为62.5%。使用胃蛋白酶和胰蛋白酶分别水解时,多肽得率为58.7%。     

葛根总黄酮提取工艺

目的:寻找出一种提取率更高更好的方法,有效地提高葛根的利用价值。方法:以乙醇为主要溶剂,使用浸提法对葛根进行总黄酮的提取,主要对溶剂的体积分数、提取所需时间、提取所需温度、固液比以及粉粒度等因素进行考察,并在单独的因素中采用正交试验,找出能够提取葛根总黄酮的最佳工艺。结果:提取温度、时间、粉粒度、固液比以及乙醇的体积分数都是影响葛根总黄酮提取率的关键因素。结论:提取葛根总黄酮的最佳工艺为:将提取温度控制为80摄氏度,提取时间控制为120分钟,乙醇的体积分数控制在百分之十,固液比控制为1:12,粉料度控制为80目。     

赤铁矿制备聚硅酸铁絮凝剂的性能研究

为利用赤铁矿、工业盐酸及硅酸钠为原料,制备聚硅酸氯化铁絮凝剂的方法并得出最佳条件,运用实验分析、文献分析及比较分析的方法,对聚硅酸氯化铁混凝性能进行了相关分析,并对聚硅酸氯化铁絮凝剂的性能进行了简要分析。结果表明,酸浸的温度、反应的时间、盐酸的浓度以及液固比均对铁的浸出有一定的影响,得到的最佳条件使铁的浸出率可达到94.58%;该方法制备的聚硅酸氯化铁絮凝剂pH适用范围较广,在整个中性和弱碱性范围内的处理效果较好;处理水的温度在10～30℃时,其效果较好;与市售的絮凝剂比较,在加药量相同的情况下,具有形成絮体速度较快,沉降速度快的优点。     

Hierarchically porous monoliths based on low-valence transition metal (Cu,Co, Mn) oxides: gelation and phase separation

Hierarchically porous monoliths based on copper (Cu), cobalt (Co) and manganese (Mn) oxides with three-dimensionally (3D) interconnected macropores and open nanopores were prepared using metal bromides as precursors via a sol–gel process accompanied by phase separation. The difficulty of gelation for low-valence metal cation was overcome by introducing a highly electronegative Br atom near to the metal atom to control the rates of hydrolysis and polycondensation. The 3D interconnected macropores were obtained using appropriate polymers to induce phase separation. The domain sizes of macropores and skeletons can be controlled by reaction parameters such as concentration and/or average molecular weight of polymers, and the amount of hydrochloric acid. The crystalline metal oxide monoliths with their 3D interconnected macroporous structure preserved were obtained after heat treatment in air.     

Improvement of ethanol production from birch and spruce pretreated with 1-H-3-methylmorpholinium chloride

BackgroundPretreatment is the critically important step for the production of ethanol from lignocelluloses. In this study, hardwood birch (Betula pendula) and softwood spruce (Norway spruce) woods were pretreated with a newly synthesized morpholinium ionic liquid, 1-H-3-methylmorpholinium chloride ([HMMorph][Cl]), followed by enzymatic hydrolysis and fermentation to ethanol.Results[HMMorph][Cl] was synthesized using inexpensive raw materials, i.e., hydrochloric acid and N-methyl morpholine, following a simple process. The influence of pretreatment time (2, 3, 5, and 8 h) and temperature (120 and 140°C) in terms of hydrolysis efficiency was investigated. Glucose yields from enzymatic hydrolysis were improved from 13.7% to 45.7% and 12.9% to 51.8% after pretreatment of birch and spruce woods, respectively, under optimum pretreatment conditions (i.e., at 140°C for 3 h) as compared to those from pristine woods. Moreover, the yields of ethanol production from birch and spruce were increased to 34.8% and 44.2%, respectively, while the yields were negligible for untreated woods.ConclusionsThis study demonstrated the ability of [HMMorph][Cl] as an inexpensive agent to pretreat both softwood and hardwood.How to cite: Mohammadi M, Shafiei M, Karimi K. Improvement of ethanol production from birch and spruce pretreated with 1‐H‐3‐methylmorpholinium chloride. Electron J Biotechnol 2019;41. https://doi.org/10.1016/j.ejbt.2019.07.004.     

利用锡废渣合成锡酸钾的研究

利用锡废渣合成锡酸钾,经浸出条件试验,得到最佳锡浸出条件为:10 mol/L盐酸,共浸出三次,每次浸出6h。锡酸钾合成最佳条件为:中和温度为20～25℃,中和PH为2.5,得到的α-锡酸用去离子水洗涤时,需调节洗涤混合液的PH为2.5。该工艺流程短,方法简单易行,产品直收率可达到97%以上,锡金属损失少,项目设备投入少,易于产业化。     

Development of biodegradation process for Poly(DL-lactic acid) degradation by crude enzyme produced by Actinomadura keratinilytica strain T16-1

BackgroundPlastic waste is a serious problem because it is difficult to degrade, thereby leading to global environment problems. Poly(lactic acid) (PLA) is a biodegradable aliphatic polyester derived from renewable resources, and it can be degraded by various enzymes produced by microorganisms. This study focused on the scale-up and evaluated the bioprocess of PLA degradation by a crude microbial enzyme produced by Actinomadura keratinilytica strain T16-1 in a 5 L stirred tank bioreactor.ResultsPLA degradation after 72 h in a 5 L bioreactor by using the enzyme of the strain T16-1 under controlled pH conditions resulted in lactic acid titers (mg/L) of 16,651 mg/L and a conversion efficiency of 89% at a controlled pH of 8.0. However, the PLA degradation process inadvertently produced lactic acid as a potential inhibitor, as shown in our experiments at various concentrations of lactic acid. Therefore, the dialysis method was performed to reduce the concentration of lactic acid. The experiment with a dialysis bag achieved PLA degradation by weight loss of 99.93%, whereas the one without dialysis achieved a degradation of less than approximately 14.75%. Therefore, the dialysis method was applied to degrade a commercial PLA material (tray) with a conversion efficiency of 32%, which was 6-fold more than that without dialysis.ConclusionsThis is the first report demonstrating the scale-up of PLA degradation in a 5 L bioreactor and evaluating a potential method for enhancing PLA degradation efficiency.How to cite: Panyachanakul T, Sorachart B, Lumyong S, et al. Development of biodegradation process for Poly(DL-lactic acid) degradation by crude enzyme produced by Actinomadura keratinilytica strain T16-1. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.005     

Enhanced pyruvic acid yield in an osmotic stress-resistant mutant of Yarrowia lipolytica

BackgroundPyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica.ResultsTo increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain.ConclusionThe PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.How to cite: Yuan W, Lin X, Zhong S, et al. Enhanced pyruvic acid yield in an osmotic stress-resistant mutant of Yarrowia lipolytica. Electron J Biotechnol 2020;44. https://doi.org/10.1016/j.ejbt.2020.01.002.     

洗氯水除砷及砷渣富集工艺研究

含砷洗氯水可采用盐酸中和,石灰和硫酸铁两段除砷的方法处理,溶液中的砷能降至0.5mg/L以下,达到国家规定的工业污水砷排放标准。一段砷渣可采用二次富集方法提高渣含砷。     

絮凝法提取木薯黄浆废水中植物蛋白质的效果研究

文章采用混凝技术提取木薯黄浆废水中的植物蛋白质物质,实验通过选取最佳的混凝剂和助凝剂种类及其最佳用量,并研究p H、沉淀时间对混凝效果的影响,为木薯黄浆废水的资源化利用提供科学依据。单因素实验结果表明:分别以1%的PAC、1%的氯化铁和1%的改性玉米淀粉处理木薯黄浆废水,三种絮凝剂的最佳投加量分别为0.133g/L、0.133g/L和0.05g/L,最佳絮凝p H分别为9、2和8,三种絮凝剂的沉淀时间均大于15min时处理效果较佳,此时木薯黄浆淀粉废水的浊度去除率均到达80%以上,COD去除率达到50%。复配实验结果表明:PAC与PAM的复配投加后,PAC投加量为0.02g/L,PAM投加量为0.002g/L,浊度去除率从80%左右上升至98.2%,COD去除率上升至51.8%,复配絮凝剂相比单一絮凝剂提取植物蛋白效果更好。     

一种同步脱氮脱硫并回收单质硫的新工艺初探

依据脱氮硫杆菌(Thiobacillus denitrificans)在厌氧(或兼性厌氧)条件具有脱硫反硝化的生理特性,采用分离筛选的脱氮硫杆菌,通过间歇试验考察了同步脱氮脱硫技术的关键因素。试验结果证明了同步脱氮脱硫技术的可行性,提出硫氮比(S2-/NO3-)和硫化物浓度是同步脱氮脱硫技术的主要因素,两者分别控制在5/3和低于300mg/L的水平可以获得较好的脱硫和反硝化效果,在此条件下,单质硫转化率最高达94%。     

正交法优化松脂直接制备对伞花烃和松脂基生物柴油的工艺条件及产品性能表征

以松脂为原料,酸改性膨润土为催化剂进行松脂直接歧化-裂解制备对伞花烃和松脂基生物柴油的研究。采用三因素四水平正交实验考察了反应温度、催化剂用量(以原料质量分数计)和反应时间对对伞花烃得率和松脂基生物柴油酸值的影响。实验结果表明,反应的优化条件为:反应温度260℃、催化剂用量为10%和反应时间120 min,对伞花烃的得率为47.9897%和松脂基生物柴油酸值为0.46 mgKOH·g-1,反应温度和催化剂用量对产品的收率和品质影响较为显著。松脂基生物柴油与O#柴油调和后低温流动性得到明显改善。