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21.
采用以磷脂为唯一碳源的限制性培养基,从富油土样中筛选得到一株磷脂酶活性较高的菌株Achromobacter sp. BIT-56. 经紫外诱变处理后其磷脂酶活力比原始菌株提高了73.3%,进一步采用紫外-硫酸二乙酯(DES)复合诱变后其磷脂酶活力提高了95.6%. 利用该菌株生产的磷脂酶进行豆油脱胶研究,其适宜的脱胶条件:脱胶温度为40 ℃,pH为5.0,加酶量为100 U/kg,加水量为4%,脱胶时间为4 h,在该条件下脱胶油中磷脂的去除率高达75.6%.   相似文献   
22.
研究地沟油的脱胶工艺,比较了磷酸脱胶、水脱胶和磷酸-水联合脱胶3种方法的脱胶效果,考察了脱胶温度、磷酸用量、酸化时间、水用量和水化时间对磷酸-水联合脱胶效果的影响,并通过正交试验对其脱胶条件进行了优化。结果表明,磷酸脱胶、水脱胶和磷酸-水联合脱胶的脱胶率分别为8.78%、68.18%和79.32%;磷酸-水联合脱胶的最优脱胶条件为:脱胶温度60℃,磷酸用量0.1%,酸化时间40 min,水用量3%,水化时间30 min,在此条件下,脱胶率为96.70%。因此,磷酸-水联合脱胶可除去地沟油中的胶体,达到生物柴油原料的要求。  相似文献   
23.
采用水解酸化工艺预处理亚麻废水。并对其进行了相关研究。在处理过程中有很多影响因素对水解酸化过程的速度和效率,以及最终产物都有重要的影响,并直接影响到水解酸化池的出水水质及处理效果。实验中主要考察了水力停留时间、进水COD、进水pH值和温度等影响因素对水解酸化池出水的影响,同时考察了水解酸化池稳定运行后对废水可生化性的改善,连续监测了水解酸化池进出水的COD、BOD、SS、pH、色度等各项指标,对类似的废水处理有一定的借鉴价值。  相似文献   
24.
添加NH4HCO3对亚麻生物脱胶的影响   总被引:5,自引:0,他引:5  
研究了在亚麻生物脱胶过程中,向沤麻水中添加NH4HCO3后沤麻液中pH值、氨基氮、NH4^ 、果胶酶活性和细菌数量的变化规律.与天然沤麻相比,亚麻生物脱胶过程中添加NH4HCO3,缩短了沤麻周期,并提高了打成麻纤维质量.图2表3参9  相似文献   
25.
桑皮纤维是一种资源可再生纤维素纤维,但在脱胶制取桑皮纤维过程中产生大量的废水,污染环境,限制了桑皮纤维的开发利用。采用调节pH值、絮凝、Fenton试剂催化氧化、活性炭吸附等物理-化学综合处理法处理桑皮脱胶废水,研究结果表明,通过物理化学法处理桑皮脱胶废水,COD总去除率达到97%以上,色度降到5倍。此方法处理效果明显、操作简单。  相似文献   
26.
In this study, a non-edible seed oil of Alexandrian Laurel (Calophyllum inophyllum L.) with higher free fatty acid content has been harnessed to produce biodiesel by transesterification process. The 20.2% free fatty acid (FFA) content was first reduced to 12.9% by using TOP degumming process. Ortho-phosphoric acid was used to esterify the refined kernel oil. Transesterification reaction was performed with NaOH as an alkaline catalyst and methanol as an analytical solvent. The effects of methanol to oil molar ratio (MR), catalyst concentration (CC), reaction temperature (TP), reaction time (TM), and stirrer speed (SS) on biodiesel conversion were studied to optimize the transesterification conditions using DOE- approach. The experimental study revealed that 9:1 MR, 0.8 wt.% CC, 60°C TP, 75 min TM and 1000 rpm SS were the optimal process control variables. The study indicated that CC was the most important control parameter in optimal methyl ester production. The optimal treatment combination yielded 97.14% of biodiesel. The profile of biodiesel was determined using gas chromatography-mass spectrometry. 1H NMR spectrum of Calophyllum inophyllum methyl ester (CIME) has been reported. The properties of the biodiesel have been found within specifications of the ASTM D6751 and EN 14214 standards and hence could be considered as a suitable alternative to diesel fuel for sustainable circulation of carbon.  相似文献   
27.
Manufacturing composites with polymers and natural fibers has traditionally been performed using chopped fibers or a non-woven mat for reinforcement. Fibers from flax (Linum usitatissimum L.) are stiff and strong and can be processed into a yarn and then manufactured into a fabric for composite formation. Fabric directly impacts the composite because it contains various fiber types via fiber or yarn blending, fiber length is often longer due to requirements in yarn formation, and it controls the fiber alignment via weaving. Composites created with cotton and flax-containing commercial fabrics and recycled high-density polyethylene (HDPE) were evaluated for physical and mechanical properties. Flax fiber/recycled HDPE composites were easily prepared through compression molding using a textile preform. This method takes advantage of maintaining cotton and flax fiber lengths that are formed into a yarn (a continuous package of short fibers) and oriented in a bidirectional woven fabric. Fabrics were treated with maleic anhydride, silane, enzyme, or adding maleic anhydride grafted polyethylene (MAA-PE; MDEX 102-1, Exxelor® VA 1840) to promote interactions between polymer and fibers. Straight and strong flax fibers present problems because they are not bound as tightly within yarns producing weaker and less elastic yarns that contain larger diameter variations. As the blend percentage and mass of flax fibers increases the fabric strength, and elongation generally decrease in value. Compared to recycled HDPE, mechanical properties of composite materials (containing biodegradable and renewable resources) demonstrated significant increases in tensile strength (1.4–3.2 times stronger) and modulus of elasticity (1.4–2.3 times larger). Additional research is needed to improve composite binding characteristics by allowing the stronger flax fibers in fabric to carry the composites load.  相似文献   
28.
沤麻过程中产生的废水量大,浓度高,气味难闻,含有大量不易降解的单宁、木质素.研究采用气浮/粉煤灰/土壤渗滤系统处理沤麻废水,结果证明,该处理系统取得了良好的效果.COD去除率为95%~98%,木质索去除率为80%~89%,处理后的出水可回用于沤麻,有很好的经济效益和环境效益.  相似文献   
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