| Rubber seed is a kind of woody plants resources with high economic value and social significance. Rubber seed kernels are rich in fat, protein, etc.. The ash content of hard rubber seed shell is low. Our country can produce 630000t-420000 t rubber seed each year. However, more than 90% rubber seed rot in the field, and utilization rate of rubber seed is less than 10%. One of the major reason is that the rubber seed contain the toxic factor--cyanogenic glucoside, and its metabolites--hydrogen cyanide(HCN) is highly toxic, which wiil poison human and animal and seriously obstacle to comprehensive utilization of the rubber seed resources.Around obstacles, this paper started with the detoxification, then used the spectral method to identify rubber seed toxic factors in chemical structure, explored the mechanism of detoxification, screened the detoxification treatments, eliminated the poison of rubber seed resources and then put forward a complete set of products using rubber seed resources for improving its added value and efficiency.This paper used the rubber seed produced in Xishuangbanna, Yun Nan Province, as raw material, and analyzed its chemical composition. The results showed that the weight of rubber seed shell accounted for 45.5% of the total seed weight, and the weight of rubber seed cake, which mainly contains 50.11% oil, 18.10% protein, 14.42% starch, 6.41% crude fiber(in terms of dry basis), accounted for 54.5% of the total seed weight. After being extracted oil, the rubber seed cake main contains 28.91% protein, 37.10% starch, 6.91% reducing sugar and 4.22% crude fiber(in terms of dry basis). According to the test results, the rubber seed shell, the rubber seed oil and the protein of the rubber seeed cake were identified as the main development objects, in the main time, to design the products and technology solutions of full compositon of rubber seed resources, with high value and recycled utilization.The weight of rubber seed cake after extracted oil accounted for above 28% of the total seed weight. The compositions such as protein, starch, oil, total sugar are more than 20% of the whole rubber seed fruit quality. So the rubber seed cake is another piece of usable resource. After oil extraction, the analysis of the main component of rubber seed cake showed that protein content in the rubber seed cake is as high as 28.91%(dry basis), and the proportion of all kinds of essential amino acid content is balanced, and there is rich in the microelements such as Mg, Fe, Zn, Mn, Ga, etc.. At the same time, the heavy metal content is lower than the set limit standard of “feed hygiene standards”. But through the isonicotinic acid-pyrazole ketone colorimetric method, the content of HCN in the rubber seed cake reach 60.50mg/kg, according to the backstepping of the experiment principle, the rubber seed cake has the toxic factor--cyanogenic glucoside, In addition, through the LC- MS spectrum experiment, the LC spectra data showed that there was at least six main chemical composition, and the MS spectra data certified that their molecular weight were, respectively, 287 D, 307 D, 287 D, 321 D, 437 D(including 289 D fragments) and 289 D(including 301 D fragments). The sugar-based of cyanogenic glucoside may be the derivatives of replaced monosaccharide and the derivatives of replaced trisaccharide. This paper treated the rubber seed cake through five detoxification treatments, such as microwave heating, baking, cooking, boiling and solvent extracting, in the same time, inspected the effect of the protein content in the rubber seed cake.The result showed that to a certain extent, these five detoxification treatments all can reduce the cyanogenic glucoside content in the rubber seed cake with different removal rate. The cooking method had the highest removal rate of 100%, and the others were the boiling method of 85.9%, the solvent extracting method of 76.7%, the baking method of 76.5%, the microwave heating method of 75.7%. The five detoxification treatments had different effect on the protein content in the rubber seed cake. The solvent extracting method had the highest protein retention rate of 126%, and the baking method of 98.5%, the microwave heating method of 97.3%, the boiling method of 90.8%, the cooking method of 87.3%. Although under the condition of high temperature and high pressure, the cooking method resulted in the decrease of protein content in the cake, its effect on detoxification is the best. It can 100% remove the cyanogenic glucoside, that means complete detoxification. So, in healthy point of view, it must give priority to the cooking method to treat the rubber seed cake for its advantage of complete detoxification. In addition, the cooking method has many advantages, such as simple process, low cost, no solvent pollution, etc..The content of rubber seed oil is more than 25% of the totle seed weight, so, in this paper, the rubber seed oil was in key development. According to the test result, the rubber seed oil had peroxide value of 1.14mmol/g, iodine value of 134.68 g I / 100 g, acid value of 34.21mg/g. Because of the characteristic of rubber seed oil, such as containing cyanogenic glucoside toxin, its high acid value, high degree of unsaturated fat and low degree of oxidation, it is mainly used in the preparation of industrial products. This paper had some research and development experiment of its industrial products, respectively.The results show that firstly, if the rubber seed oil was used to prepare epoxy oil, with epoxy value as an index, the optimum process conditions are formic acid in the material liquid mass ratio of 0.12:1, the hydrogen peroxide in the material liquid mass ratio of 0.5:1, the reaction temperature of 50℃, the reaction time of 6h. Under the optimizing condition, the preparation of epoxy rubber seed oil has the recovery of 92%. Then the epoxy rubber seed oil and epoxy soybean oil(reference sample) were tested its performance and characterization of FT-IR. The results show that the epoxy value of epoxy rubber seed oil can reach 5.02% and the FT- IR spectras of these two kinds of epoxy oil are very close. To a certain extent, it can explain that epoxy rubber seed oil is very close to the epoxy soybean oil on the structure.Secondly, if the rubber seed oil was used to prepare biodiesel, with conversion rate as an index, the optimum process conditions are alcohol oil ratio of 1:15, the dosage of catalyst of 1.5%, the reaction temperature of 65℃, the reaction time of 8h. Under the optimizing condition, the preparation of biodiesel rubber seed oil has the conversion rate of 91.86%. The test results showed that the opening kinematic viscosity, flash point and ash content of rubber seed biodiesel accord with the standard of ASTM(American) of biodiesel and its value is close to the commercial 0# diesel oil. It can be considered as the 0# diesel alternative products.The ratio between the weight of rubber seed shell and the weight of the whole rubber seed reached 45.5%. The rubber seed shell is an important biomass resources. And it is hard. The rubber seed shell has the low ash content of 0.33%, and high lignin content of 25.80%, cellulose content of 7.31%, hemicellulose content of 19.92%. In addition, the heavy metals--arsenic, lead, mercury were not found in the rubber seed shell, and the content of cadmium is far lower than the set limit standard of the "feed hygiene standards". This paper apply the shell to the industrial field and design the develop experiment of its preparation of the activated carbon product.The results showed that if the rubber seed shell was used to prepare the activated carbon product, with the iodine adsorption value as an index, the optimum process conditions are activator concentration of 40%(mass fraction), impregnation time of 24 h, irradiation time of 10 min and irradiation power of 700 W. Under the optimizing condition, the preparation of the activated carbon product has the yield of 28.7% and the iodine adsorption value of 830mg/g. Under the optimizing condition, using different types of activator to prepare the rubber seed shell activated carbon, and carring on their specific surface area and pore size distribution analysis, infrared spectrum analysis, X-ray diffraction analysis, the surface morphology observation. By all sorts of spectra characterization, it showed that the activated carbon prepated with zinc chloride as the activator has higher quality. Through the BET analysis, its specific surface area was 995.68m2/g and its average pore diameter was 2.66 nm. In the FT-IR spectrum diagram, characteristic peaks showed that its cellulose was basicly decomposed. The number absorption peaks was small and their strength was weak, that means the number and the variety of its surface functional groups were small. This activated carbon may contain the following functional groups: carboxyl, polyphenols, amino, alcoholic hydroxyl, etc.. The XRD diffraction spectrum of this activated carbon had the strongest intensity of the diffraction peaks in the figure. It represents the higher degree of graphitization and more order internal structure. The SEM spectra showed that this activated carbon had more developed and uniform pore structure. |
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