Chemistry of antiscalants - Essay Example

Conversely, Phosphonates, polyphosphates and polycarboxylates react with minimal quantities (Singh et. al., 2008). Threshold inhibitors are the name that refers to the chemical agents that inhibit scale and work at quantities below the stoichiometric level. These inhibitors foil the whole process of precipitation. Various mechanisms take place when interfering with the process of precipitation. The first manner is the modifying of the crystals into shapes that make it impossible for attachment with other crystals.

Secondly, the inhibitors attack the forces that bind the particles into precipitation to break the bond necessary for the precipitation. The third mechanism is through impeding the growth of the particles to bring a non-precipitation zone. Despite the effectiveness of the antiscalants, other indispensable factors determine the whole process. These factors comprise of presence of other ions in the solution, the temperature, the PH and the ratio of super saturation. Moreover, the heaviness of a polymer matters a lot when the antiscalant is polymer (Singh et. al., 2008).

CACO3 crystallization is a process that is intricate and requires great understanding to know the reaction that takes place with the antiscalant. The various mechanisms with which the antiscalant inhibits the precipitation are under one method of “charges attraction”. The antiscalant is always negatively charged and it gets attracted to the area with the crystals, which is positively charged. The definition of threshold inhibition is assumed from this description. Threshold inhibition thus refers to the fusing of the particles of the inhibitor to the crystal-filled arena that is rich with ions.

The surface of the crystallization zone tends to be loose and hence creates a space for absorption of the inhibitor’s particles. Once the inhibitors have penetrated to the inside of the crystals, the formation of crystals is in interference. It delays the beginning of crystallization since the walls that would bind the crystals are filled with the inhibitors particles. The first crystals cannot be detected since the inhibitors particles impose a derailment between the period of super saturation state and crystallization (Singh et. al., 2008).

Consequently, the crystals form but the inhibitors attack to tamper the growth sites. It thus obstructs the normal reaction that would have to happen. The inhibitors modify and alter the growth of the crystals. Results from the modification of the crystals, is retarded crystals that do not have the strength to stick on metal materials. These crystals are then electrostatic charged and thus posses repulsion with particles with the same side charges. It makes the crystals not to converge and clot (Singh et. al., 2008).

There is a common fact that phosphonates are better threshold inhibitors than polycarboxylates. Contrarily, polycarboxylates are better dispersants than phosphonates. Both chemical agents show their reaction when in a solution in inhibiting scale threshold. In a condition where the level of super saturation is low, the phosphonates can be the ultimate solution. Conversely, where the level of super saturation is high, polycarboxylates can salvage the reaction (Singh et. al., 2008). Polycarboxylates have properties that can help in dispersing of particles that are useful in a condition of high super saturation. It is a