两步法催化潲水油制备生物柴油的研究

采用两步法催化高酸值潲水油制备生物柴油,第一步先用硫酸铁催化潲水油中游离脂肪酸和甲醇酯化生成脂肪酸甲酯(生物柴油),然后再用氢氧化钾催化潲水油中的甘油三酯和甲醇进行酯交换。结果表明,硫酸铁对酯化反应具有很强的催化活性,而且可以回收利用。通过正交试验得到最佳酯化反应参数:硫酸铁用量2%,反应温度95℃,醇油摩尔比10∶1,反应时间4 h,该条件下游离脂肪酸酯化率达97.22%。酯交换条件为:KOH用量1%,反应温度65℃,反应时间1 h,醇油摩尔比6∶1。经过两步催化,产品中总的脂肪酸甲酯(生物柴油)含量达97.02%。该两步催化法具有不产生酸化废水,不需要耐强酸设备,反应时间短,转化率高,同时硫酸铁可以回收重复利用等优点。     

固体碱催化地沟油制备生物柴油工艺研究

以地沟油为原料,硫酸铁作为催化剂,通过酯交换反应制备生物柴油。酯交换反应考察醇油摩尔比、反应时间、反应温度和催化剂氢氧化钾的用量对降酸后的地沟油酯化产率的影响。结果表明:醇油摩尔比为7∶1,反应时间为40min,催化剂氢氧化钾用量为油重的1.0%,反应温度为65℃时,生物柴油得出产率含量为96.53%。     

两步法催化高酸值油脂生产生物柴油的研究

以高酸值废油脂为原料,采用两步法即先用硫酸氢钠为催化剂催化废油脂中的游离脂肪酸和甲醇酯化反应降低原料的酸值,然后分离出硫酸氢钠,加入氢氧化钠催化中性油酯交换生产生物柴油。酯化反应的最佳条件为：温度65℃,催化剂硫酸氢钠用量4%,醇油摩尔比为12∶1,反应4h;酯交换反应条件是：在65℃下加入0.8%的氢氧化钠,醇油摩尔比为6∶1,反应时间为1h,最终生物柴油的得率为93.2%。该两步催化法具有不产生酸化废水,不需要耐强酸设备,同时硫酸氢钠可以回收重复利用等优点。     

两步法试制生物柴油的研究

采用硫酸作催化剂,利用高酸值油脂与甲醇进行预酯化反应;再用氢氧化钠作催化剂,进行酯交换反应.结果表明:预酯化的反应条件为:醇油摩尔比8∶1、催化剂用量0.25%、反应时间1h,游离脂肪酸的转化率达到97.2%;酯交换的反应条件为:醇油摩尔比6∶1、催化剂用量0.5%、反应时间0.5h,生物柴油的收率可达98%.     

钙基固体碱法制备生物柴油工艺的研究

研究了钙基负载型固体碱制备生物柴油的酯交换反应,通过正交试验得出菜籽油制备生物柴油的最佳工艺条件为:反应温度70 ℃、反应时间6 h、催化剂用量4%,醇油摩尔比8∶1,在最优条件下,生物柴油转化率97.62%.     

利用地沟油制备生物柴油

以废弃地沟油为原料,经预处理后采用两步酯化工艺将其转化为生物柴油.第一步为酸催化预酯化反应,主要是将地沟油中的游离脂肪酸转化为脂肪酸甲酯;第二步为酸催化转酯化反应.主要是进一步将地沟油中的甘三酯转化为甲酯和甘油.通过正交实验得到预酯化反应的最佳条件为:醇油摩尔比10:1、催化剂用量1.0%、反应温度70℃、反应时间4 h;转酯化反应的最佳条件为:醇油摩尔比20:1、催化剂用量6%、反应温度70℃、反应时间4 h.在最佳反应条件下,甘三酯的酯化率可达到86.89%.     

氨基磺酸催化合成脂肪酸丁酯的研究

以氨基磺酸为催化剂,油酸及菜籽油与正丁醇分别进行酯化反应与酯交换反应制备脂肪酸丁酯。并利用气相色谱及红外光谱对产物进行分析及结构表征。考察了醇(正丁醇)油(油酸及菜籽油)摩尔比、催化剂用量、反应温度和反应时间对油酸及菜籽油转化率的影响。结果表明,油酸酯化反应的最佳工艺条件为:醇油摩尔比3∶1,催化剂用量为油酸质量的0.8%,反应温度110℃,反应时间1.5 h,此时油酸转化率达到88.6%,产品收率为83.5%;菜籽油酯交换反应的最佳工艺条件为:醇油摩尔比10∶1,催化剂用量为菜籽油质量的1.0%,反应温度115℃,反应时间2.0 h,此时菜籽油转化率达到85.6%,产品收率为80.1%。     

油莎豆油制备生物柴油的研究

以油莎豆油为原料,四甲基氢氧化铵为催化剂,通过酯交换反应制备生物柴油.通过单因素试验和正交试验研究了催化剂用量、醇油摩尔比、反应温度和反应时间对生物柴油转化率的影响.结果表明,酯交换反应的最佳反应条件为:催化剂用量为油莎豆油质量的0.5％,醇油摩尔比为6∶1,反应温度50℃,反应时间4.5h.在最佳反应条件下,生物柴油转化率达94.5％.     

米糠油制备生物柴油工艺条件的试验研究

以米糠油为原料,氢氧化钠为催化剂,采用酯交换法制取生物柴油.考察了醇油摩尔比、催化剂用量、反应时间和温度对产品转化率的影响.正交试验结果表明,米糠油在酯交换反应的最优条件为:醇油摩尔比6∶1,催化剂浓度0.8%,反应温度60℃,反应时间60min.试验所得的生物柴油质量指标达到德国DIN V 51606标准,并接近0#柴油的中国国家标准.     

硅酸钠固体催化剂的制备及催化酯交换反应

以NaSiO3*9H2O为原料,通过高温煅烧、研磨、过筛等工艺制得硅酸钠固体催化剂,将其用于棉籽毛油的酯交换反应制备生物柴油.考察了醇油摩尔比、催化剂用量、反应时间等对转化率的影响.研究表明,催化剂最佳制备条件为:煅烧温度200 ℃,煅烧时间1 h,粒度60目.在常压、醇油摩尔比8∶ 1,催化剂用量7%,反应温度65 ℃,反应时间1 h的条件下,酯交换反应转化率达到99.45%;催化剂重复使用10次后,转化率仍在90%以上.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.