The Study Of The Salting Effect Of CO₂ And Carbon Dioxide Flux Of Sediment-sea Interface

This article determines the solubility of carbon dioxide by coulometric titration and calculates the salting-coefficient of CO2 in different electrolyte solutions at 3 temperatures. It attains the rule of ks. After calculating the theoretical model calculation of Debye-McAulay theory (DMT), Conway-Desnoyers -Smith theory (CDMT), McDevit-Long theory(IPT) and Scaled Particle theory(SPT), the order of salting coefficients were explained. Using coulometric titration , this article determines the dissolved inorganic carbon in Changjiang estuary, Jiaozhou bay, East China Sea and presents the carbon flux between sea and sediment, also gives the diffusion direction. This article explains these with factors of wave, biology and chemistry. The main results are as follows.1. the systems studied of salting effect including l:ltype Nad, KC1, KF, NaF, NaBr, KBr; 1:2 type Na2SO4, K2SO4; 2:1 type MgCl2, CaCl2, SrCl2; special electrolytes: NaClO4?NaNOs.2. the rules of the salting effect in different electrolyte solutions and at different temperature are:(1) ks increases with the increasing of temperature for 1-1, 2-1 salts.(2) the influence of different electrolytes on salting coefficients at the same temperature:(1) 1 -1 type salts, NaF > KF >NaCl > KC1 > NaBr > KBr(2) the comparity of k, of 1-1 type salt with the same anion and different cation,with the same cation and different anion:when the cation is the same, k, is smaller with the largening of the radius ofanion.Na: NaF > NaCl> NaBrK: KF >KC1 > KBfwhen the anion is the same, ks is smaller with the largening of the radius of cation.F: NaF > KF Cl: NaCl > KC1 Br: NaBr > KBr(3) 1-2 type, the change order of ks in different electrolytes of the same temperature:Na2SO4 >K2SO4(4) 2 - 1 type, the change order of ks in different electrolytes of the same temperature:SrCl2 > CaCl2 > MgCl2(3) The salting effect is more intensity if the electro valence is greater. The ks of 2-1 type salt is bigger than the 1-1 type in the same anion condition; in the same cation condition, the salting effect is more intensity if the electrovalence is greater ,Na2SO4 >NaCl, K2SO4>KC10(4) The ks of NaClO4 is negative, this means that salting-in effect takes place in thiselectrolyte solutions.3. ksin different electrolyte solutions were calculated and explained by four theoretical model of DMT, CDMT, IPT, SPT.4. Determined the flux of C between sediment and sea in Changjiang estuary, Jiaozhou bay and East China Sea. tthe flux was calculated and explained.