| In the paper, the preparation process of nano-hydrophobic catalyst Pt/C/PTFE has been investigated. Technologic conditones and influencing factors for preparing nano -Pt particles, deposited temperature of nano -Pt particles, processing pressure of carrier and properties of nano-hydrophobic catalyst Pt/C/PTFE were thoroughly studied.Nano-Pt particles were synthesized by the method of microemulsion reaction, and the ratio of microemulsion system's three components (CTAB/C8H17OH/H2O) was researched. The results showed that the ratio was a key factor to determine whether the microemulsion system can be formed. The microemulsion system cannot be formed and it exhibited a kind of opacity latex when the ratio of CTAB/ C8H17OH was 1:1 or 1:2. While the ratio of CTAB/ C8H17OH reached or exceed 1:3, the microemulsion system can be formed.The soluble capacity of Pt salt in the kind of microemulsion system was investigated and it was suitable to keep Pt salt below 0.02%(wt).The size of nano-Pt particles in the different water content was measured by TEM.The results showed that the size of nano-Pt particles increased with addied water content. Temperature had a substantial influnce on the aggregation of nano-Pt particles, with the increasing of temperature, the aggregation was aggravated. Reaction process of preparing nano-Pt particles was also observed.. It can be finished in the 15 minutes at the room temperature. As temperature increased, the reaction became more intensive, and it be can finished instantaneously and the shape of nano-Pt particles was not desired .Nano-Pt particles in the different heating treat temperature was studied by XRD. It tested that surfactants existed in the XRD peak at 100℃ and cannot be observed impurities at 200℃. As temperature increasing at 300℃, XRD peaks of nano-Pt particles exhibited sharply and narrowly. The weight loss of not washing sample was measured by TG. The results showed that the biggest ratio of weight loss was about 92%.A method to deposit the Pt on the carrier directly was brought forword firstly in order to fabricate nano-hydrophobic catalyst. Under different temperature, the depositing quantities of nano-Pt particles on surface of carrier were measured.The results showed that the deposition quantities of nano-Pt particles increased linearly within l5h at room temperature,and as time going on, the rate of depositing decreased and deposition quantities increased slowly and were almost stable. With the temperature increasing, the depositing rate increased and the time of reaching a stable deposition quantities was shorten.The processing pressure effected on the ratio surface area and aperture of carrier C-PTFEof nano-hydrophobic catalyst Pt/C/PTFE was investigated. It exhibited that the ratio surface and aperture became small as pressing pressure increasing,.and the strength of carrier is not good and was fragile at 1.0 Mpa. The carriers strength increased and was not fragile within pressing pressure of 1.52.5Mpa.The section and shape of nano-hydrophobic catalyst Pt/C/PTFE were observed by SEM. However, the state of Pt particles on the surface of the carrier was measured by XPS , and the results showed that its chemical valence was zero and not other chemical valence state exited . In the system of hydrogen isotope HDO-H2O, the factors effect on catalytic activities of nano-hydrophobic catalyst Pt/C/PTFE were investigated . The different ratio of hydrophobic catalyst with filling had a large influence on catalytic activities. When the ratio of hydrophobic catalyst with filling was 1:4, the rate of exchange reaction was the rapidest.As reaction temperature increased,the catalytic activities date Kya was also increased, When the temperature exceed 75℃, the increasing degree of Kya become to weaken. Kya of Pt/C/PTFE by using different technology existed a large difference. In the same experimental condtiones, Kya of nano-hydrophobic catalyst is one times higher than that of Pt/C/PTFE by the immersion method. However, th...
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