The development of new recycling-type treatment for nitrate wastewater using lead compounds

[1]用蒸汽分流添加铅（II）氧化物（II）氧化物（II）氧化物（II）氧化物在373 K处添加到0.1- 2 M NH_4NO_3解决方案，并在0.5- 2 h处恢复NH_3解决方案。PbO/NO_3^的摩尔比率的影响，以及蒸汽分流时间对NO_3^的去除和NH_3的恢复，以及测试的基本先导成分（II）硝酸盐。removal of NO_3^- as pb（NO_3） _2·5 pb（OH）_2 and recovery of NH_3 reached ca.100%at the PbO/NO_3^- molar ratio of 4 for 1 h。Above 0.5 M NH_4 NO_3， the removal of NO_3^- was independent on the initial concentration of NO_3^-. NH_3 was analogous to the removal of NO_3^-. [2]减少钠硝酸盐解决方案由在NaNO_3溶液中的原位缓冲液去除的领先平板硝酸盐离子减少由精细的Pb粉末产生的连续去除Pb板的缓冲液去除。在25-80 C以下，初始概念 ... More ion of NO_3^- 0.01- 0.1 M，rotation speed of buff 400- 800 rpm， 20- 100% nitrate ion被降低到NO_3^-， N_2和/或NH_3在12 h内。自NO_3^-降低率以来，N_2和NH_2格式的比率非常缓慢，最大百分比分别为14，6，平均为12 h。Pb在12小时时氧化化，使PbO含有不反应的Pb。在生产较大的Pb颗粒（20毫米）时，使用焦炭缓冲（#120）增加旋转速度，降低率NO_3^-增加到裸露Pb的数量和Pb的表面区域，通过去除PbO层生长在Pb颗粒上。However，降低了Pb降解的有效性，增加了不反应性Pb核的数量。[3]用湿球铣削反应器减少钠氮含量的速率，用金属氧化物在铅滴表面通过减少氮含量的表面不断地被去除，与彼此接触低于5 -80 ℃ C，初始浓度NaNO_30.05 -0.1M，球铣削旋转速度，欧米茄， 80- 180 rpm， NO_3^-被减少到NO_2^-快速，然后缓慢地到达N_2和N_3。NO_3^- was降低到NO_2^- 32- 100% in 10 h，但降低率NO_2^- was非常低，因此N_2和NH_3的最大百分比从NO_2 ^- were仅6和10%，响应。以上40-C，NO_3^- was降低了zero-order反应和NO_2^- was formed corresponding to the reduction stoichiometry。降低率为omega^<1/2>，而特定激活能量为27.5 kJ-mol ^<-1>，但与NO_3^-集中无关。这些结果可能会认为，确定速率的步骤是粒子表面上的PbO layr的peeling。以下25-C，降低速率被降低为反应时间，而表面并不覆盖完全与PbO的速率降低。Less（低）

[1] Recovery of ammonia and nitrate ion from ammonium nitrate in waste water by steam distilllation adding lead (II) oxide.Lead (II) oxide was added to 0.1-2M NH_4NO_3 solutions at 373K to precipitate basic lead (II) nitrates and to recover NH_3 simultaneously by steam distilllation for 0.5-2h. Effects of the molar ratio of PbO/NO_3^- and steam distilllation time on the removal of NO_3^- and recovery of NH_3, and the composition of basic lead (II) nitrate were examined. The removal of NO_3^- as pb(NO_3) _2・ 5pb(OH)_2 and recovery of NH_3 reached ca.100% at the PbO/NO_3^- molar ratio of 4 for 1 h. Above 0.5M NH_4NO_3, the removal of NO_3^- was independent on the initial concentration of NO_3^-. The recovery of NH_3 was analogous to the removal of NO_3^-.[2] Reduction of sodium nitrate solution by in situ buff abrasion of leadplateNitrate ions were reduced by fine Pb powder produced by continuous abrasion of Pb plate with buff abrasive in NaNO_3 solution. Under 25-80ﾟC,initial concentrat … More ion of NO_3^- 0.01-0.1M,and rotation speed of buff 400-800rpm, 20-100% nitrate ion was reduced to NO_3^-, N_2 and/or NH_3 within 12h. Since reduction rate of NO_3^- was extremely slow, maximum percentages of formed N_2 and NH_2 were 14,6, respectively at 12h. Pb was oxidized at 12h to PbO containing unreacted Pb.In the case of producing bigger Pb particles (20mum) by using coarse buff (#120) and increasing rotation speed, the reduction rate NO_3^- increased due to an increase in amount of abrabed Pb and surface area of Pb by removing PbO layr grown on Pb particles. However, the reduction efficiency of Pb decreased with increasing amount of unreacted Pb core.[3] Reduction rate of sodium nitrate by lead drops with wet-ballmillingIn a ballmill reactor, metal oxides formed on the lead drops surface by reduction of nitrate ions were continuously removed by contacting with each other.Under5-80ﾟC,initial concentration of NaNO_3 0.05-0.1M,and ballmill rotation speed, omega, 80-180rpm, NO_3^- was reduced to NO_2^- fast, then slowly to N_2 and NH_3. NO_3^- was reduced to NO_2^- 32-100% in 10h, but the reduction rate of NO_2^- was very low, so the maximum percentages of N_2 and NH_3 from NO_2^- were only 6 and 10%, respectively.Above 40ﾟC,NO_3^- was reduced under zero-order reaction and NO_2^- was formed corresponding to the reduction stoichiometry. The reduction rate was proportional to omega^<1/2>, and the apparent activation energy was 27.5kJ-mol^<-1>, but independent of the NO_3^- concentration. These results may suggest that the rate determining step is the peeling of PbO layr on the particle surface. Below 25ﾟC,the reduction rate decreased with reaction time as the surface was not covered completely with PbO due to the lowering of the rate. Less