The invention discloses a device and a method for detecting total
cyanide and
sulfide in a water solution by employing direct conversion. The method comprises the following steps: feeding a sample solution of which the pH is greater than or equal to 11 into a six-way valve quantitative loop to quantify through an online filter, feeding excessive sample solution into a
liquid waste bottle; switching a six-way valve, pumping a pure water
solvent as a carrying current, pushing out the sample solution, and pumping a water solution containing a stabilizer and an exchanger in advance; after mixing with the sample coming from quantitative loop samples, switching a three-way valve, and refluxing into a storage
bottle, further pushing the solution to be mixed evenly in a mixing
pipe by virtue of the pure water
solvent; entering a photolysis device to carry out photolysis until reaching a capture column in the six-way valve in an
ion chromatograph; locking a to-be-detected object, feeding a non-to-be-detected object into the
liquid waste bottle; rising the capture column by using an eluting solution, and entering a separation post; sequentially discharging the
sulfide and
cyanide; and respectively detecting the
sulfide and the
cyanide by virtue of an
ampere detector, and then rinsing the
separation column in a reinforcing manner. Compared with an existing
national standard method, the method disclosed by the invention is green, safe, environment-friendly, and little in interference; the analysis time, the
laboratory safety and the cost are obviously improved; and use of a toxic
reagent is also reduced.