Effects of physical refining on contents of waxes and fatty alcohols of refined olive oil

Changes in the contents of waxes and fatty alcohols during deodorization/physical refining of bleached olive oil were studied. Experiments were carried out with 1.85% acidity oil, which was physically refined in a discontinuous deodorizer of 250-kg maximum capacity using nitrogen as stripping gas instead of steam. The variables studied were load and temperature of oil in the deodorizer as well as N₂ flow. Analyses of waxes and alcohols were carried out at different operation times. The maximum content of wax was always observed when the oil reached the deodorization temperature. The variation in the wax content depended on temperature and N₂ flow. Wax decomposition started and continued during the operating time, and a progressive decrease, which was pronounced between 3 and 4 h, was observed. Small changes in waxes were observed between 4 and 5 h. Total content of fatty alcohols diminished throughout the operating time, and changes did not depend on the variables studied.     

Oxidative stability of high-fatty acid rice bran oil at different stages of refining

The contents of natural antioxidants and the oxidative stability of rice bran oils at different refining steps were determined. Tocopherols and oryzanols were constant in crude and degummed oils but decreased in alkali-refined, bleached and deodorized oils. The process of degumming, alkali-refining, bleaching and deodorization removed 34% of the tocopherols and 51% of the oryzanols. During storage of deodorized oil for 7 wk, 34% of the tocopherols and 19% of the oryzanols were lost. The maximum weight gain, peroxide value and anisidine value were obtained from alkali-refined oil during storage. The order of oxidation stability was crude ≥ degummed > bleached = deodorized > alkali-refined oil.     

Alternative hydrocarbon solvents for cottonseed extraction: Plant trials

Hexane has been used for decades to extract oil from cottonseed and is still the solvent of choice for the edible-oil industry. Due to increased regulations as a result of the 1990 Clean Air Act and potential health risks, the edible-oil extraction industry urgently needs an alternate hydrocarbon solvent to replace hexane. Based on laboratory-scale extraction tests, two hydrocarbon solvents, heptane and isohexane, were recommended as potential replacements for hexane. A cottonseed processing mill with a 270 MT/day (300 tons/day) capacity agreed to test both solvents with their expander-solvent process. Extraction efficiencies of isohexane and heptane, judged by extraction time and residual oil in meal, refined and bleached color of miscella refined oil, and solvent loss, were comparable to that of hexane. However, fewer problems were encountered with the lower-boiling isohexane than with the higher-boiling heptane. With isohexane, the daily throughput increased more than 20%, and natural gas consumption decreased more than 40% as compared to hexane.     

冬虫夏草多糖的研究开发

该项目对虫草菌菌种SD-801进行了分离纯化及选育,筛选出最佳菌株C-235,虫草多糖含量在10％～12％。经过提取及精制,虫草多糖含量达到45.9％。该项目还对多糖组分进行了分析,通过红外光谱、核磁共振得出各组分结构特点。急性毒性试验及药理试验表明,虫草多糖无毒,是很有前景的抗癌药物。虫草多糖的提取、精制工艺还有待于进一步优化,以降低生产成本和提高产品纯度。     

利用超声细化羟基磷灰石制备胶原-羟基磷灰石复合膜的研究

为了克服市售颗粒状羟基磷灰石（HA）颗粒过大，与胶原复合后界面结合不充分的缺点，在不破坏HA本体晶格结构的前提下，采用超声细化法制备HA-胶原复合膜，通过对材料的拉伸强度的测试以及SEM形貌观察证实了此法的优越性。通过XRD、DSC和IR等手段考查HA在超声处理后与胶原的复合过程中，HA本体结构是否遭到破坏，界面是否发生化学反应以及超声细化处理是否有利于两种材料的复合。结果表明，HA经超声细化处理后，胶原-HA复合材料界面的黏合效果明显好于胶原-HA直接混合的效果，HA经超声细化后本体的晶格结构没有被破坏，而且胶原-HA复合膜界面有化学键C-O-P形成，宏观上表现为材料的拉伸强度增加。     

大孔树脂法精制甘草酸

介绍了用大孔树脂从甘草中分离精制甘草酸的方法。大孔树脂是目前广泛采用的分离天然产物的方法。用大孔树脂精制甘草酸,使甘草酸和其他杂质得到很好的分离,明显改善了甘草酸的质量。在纯度测定时,采用香草醛-硫酸比色法能准确测定甘草酸纯度。另外,实验使用草酸还原Fe3+的方法改善产品颜色,并在进样前先用活性炭脱色,这两种方法同时使用有效地改善了产品的颜色。     

Galvanostatic and microscopic studies of nodulation during copper electrolysis

The galvanostatic technique on a laboratory scale has been shown to be a useful tool in detecting the presence of nodules on the cathode during copper electrodeposition by using the value of the starting electrolytic potential and by the presence of a cathodic polarization peak on the potential–time curve. Studying the morphology of the deposit with a scanning electron microscope at various magnifications confirmed the galvanostatic results. It is postulated that inappropriate concentrations and/or ratios of the additives (thiourea, gelatin and chloride ions) are associated with a certain current density that generates intergranular microcracks due to adsorption of the additives and leads to the formation of nodules at the macroscale.     

炉外精炼用耐火材料提高寿命的途径及其发展动向

结合VOD与RH介绍了造成炉外精炼蚀损严重部位的原因。从MgO-Cr2O3、MgO-CaO、MgO-C、MgO-CaO-C、MgO-MgO·Al2O3等耐火材料性能及在精炼中的作用介绍了如何选择耐火材质;从接触角、熔渣粘度、形成高熔点化合物、气孔微细化以及炉渣成分控制、双饱和与精炼温度等方面介绍了提高炉外精炼用耐火材料寿命的途径。最后结合镁铬、镁钙、MgO-C、镁钙碳与无铬耐火材料介绍了炉外精炼用耐火材料的发展动向,并对MgAlON结合镁质耐火材料在炉外精炼中的研究与应用进行了评估与预期。     

不锈钢冶炼用不烧镁钙砖的研制及应用

介绍了冶炼不锈钢用不烧镁钙砖的研制过程及其在冶炼不锈钢的 90tAOD炉炉帽和 90t装入包包底的应用情况。结果表明 :在 90t装入包包底的使用寿命达 1 1 0次 ,最大侵蚀速度仅为 1 .50mm·次 -1 左右 ;在 90tAOD炉炉帽上的使用寿命达 2 1 7次 ,最大侵蚀速度仅 0 .55mm·次-1 ,但存在裂纹和剥落现象 ,今后应改进砖型设计 ,增加调整砖 ,以消除砌缝 ,提高衬砖的整体性和稳固性     

提高科技创新实力实现我国炼油工业的持续发展

分析了21世纪我国炼油工业要持续发展，国际竞争能力要大力提高，涉及到的原油资源战略、现代化企业管理、行业体制和机制、企业机构调整、人才机制及科技创新等多方面问题，并就产品质量、深度加工、油化一体化、信息技术和运输燃料替代技术，以及如何提高科技创新能力、加强科技开发等技术发展战略，提出了一些对策和建议。