REVIEW: TEKNOLOGI PEMBUATAN SORBITOL DARI TEPUNG TAPIOKA

Sugar alcohol or sorbitol is a derivative product of carbohydrates, namely glucose through the hydrogenation process with hydrogen gas. The glucose used comes from flour, because the carbohydrate content in tapioca flour is considered the highest compared to other flour ingredients. Before the hydrogenation process is carried out, tapioca flour is enzymatically hydrolyzed so that the starch is broken down into glucose. The process of making sorbitol can be done in two ways, namely the electrolysis reduction process and the hydrogenation process with the help of a nickel catalyst. This literature study aims to determine the technology for making sorbitol and its advantages and disadvantages, both in terms of product and process, so that it can be used as a reference in selecting processes in sorbitol manufacturing plants. The catalytic hydrogenation process has advantages, namely the resulting yield is greater and the operating costs are relatively cheaper. The catalytic hydrogenation process also has several disadvantages, namely that it requires good safety handling because it requires high pressure in the process.

Catalytic Hydrogenation of Post-Mature Hydrocarbon Source Rocks Under Deep-Derived Fluids: An Example of Early Cambrian Yurtus Formation, Tarim Basin, NW China

As a link between the internal and external basin, the deep derived fluids play a key role during the processes of hydrocarbon (HC) formation and accumulation in the form of organic-inorganic interaction. Two questions remain to be answered: How do deep-derived fluids affect HC generation in source rocks by carrying a large amount of matter and energy, especially in post-mature source rocks with weak HC generation capability? Can hydrogen and catalysts from deep sources significantly increase the HC generation potential of the source rock? In this study, we selected the post-mature kerogen samples of the early Cambrian Yurtus Formation in the Tarim Basin of China. Under the catalytic environment of ZnCl2 and MoS2, closed system gold tube thermal simulation experiments were conducted to quantitatively verify the contribution of catalytic hydrogenation to "HC promotion" by adding H2. The catalytic hydrogenation increased the kerogen HC generation capacity by 1.4–2.1 times. The catalytic hydrogenation intensity reaction increased with temperature. The drying coefficient of the generated gas decreased significantly as the increasing yield of heavy HC gas. In the simulation experiment, alkane δ13C becomes lighter after the catalytic hydrogenation experiment, while δ13CCO2 becomes heavier. In the process of catalytic hydrogenation, the number of gaseous products catalyzed by ZnCl2 is higher than that catalyzed by MoS2 under the same conditions, indicating that ZnCl2 is a better catalyst for the generation of gaseous yield. Meanwhile, Fischer-Tropsch synthesis (FFT) reaction was happened in the catalytic hydrogenation process. The simulation experiment demonstrates that hydrogen-rich components and metal elements in deep-derived fluids have significant catalytic hydrogenation effects on organic-rich matter, which improved the HC generation efficiency of post-mature source rocks.

Continuous Catalytic Hydrogenation of Carbon Dioxides on Immobilized Ru Functionalistic Catalysts

Functionalized catalyst preparation is a new and attractive method for hydrogenation of carbon dioxides. Three kind of carriers were functionalized firstly and then Ru was immobilized on the carriers. Continuous catalytic hydrogenation process was used to evaluate the activity of the catalyst on fixed-bed. It was found that the main production are formic acid and CO at 10MPa, and both the selectivity and recovery of CO are more than 90%, the hydrogen reaction mechanism could be explained with the reversed water gas reaction process. This may offer a new way for the reuse of CO2.

The fall of the traditional lipid hypothesis

The Finnish recommendation "Diagnosis and treatment of hypercholesterolaemia and other hyperlipidaemias in adults"(6) is mainly based on the traditional lipid hypothesis. The expediency of the recommendation should be reviewed in the light of the latest studies on diet, blood serum cholesterol and mortality. According to this information: 1. The mortality of the population increases both at high and at low cholesterol levels. The U-shape (Fig. 1) illustrating mortality vs. blood cholesterol level is different for men and women. Hence, the optimum blood cholesterol range should be set for men and for women separately. The present target value, below 5 mmol/1 for the entire Finnish population, is not reasonable. 2. The trans fatty acids formed in the catalytic hydrogenation process of polyunsaturated fatty acids have an unfavourable effect on blood cholesterol and may contribute to the occurrence of CHD. Thus the Finnish recommendation to increase the use of margarines is not well-founded. There are considerably better alternatives on the Finnish yellow fat market (Table 1).