Detecting method for contents of cadmium, lead, mercury and chromium in plastic
A detection method and technology of chromium content, applied in the detection of lead, mercury, chromium content, and cadmium in plastics, can solve the problems of toxicity, protein denaturation, etc., achieve good repeatability and reproducibility, high accuracy, and simple detection method Effect
Patent Information
- Authority / Receiving Office
- CN · China
- Current Assignee / Owner
- Publication Date
- 2014-06-11
- Estimated Expiration
- Not applicable · inactive patent
Smart Images
Figure 1
Abstract
Description
technical field
[0001] The invention relates to a method for detecting the content of heavy metal elements, in particular to a method for detecting the contents of cadmium, lead, mercury and chromium in plastics. Background technique
[0002] Heavy metal elements generally refer to metal elements with an elemental density greater than 4500kg / m3 under standard conditions, which are different from light metal elements (such as aluminum and magnesium). Common heavy metal elements are cadmium (Cd), mercury (Hg), arsenic (As), Cr (chromium), copper (Cu), barium (Ba), lead (Pb), etc. The ions of heavy metal elements are generally toxic. For example, copper is non-toxic, but copper ions denature proteins and are toxic.
[0003] Renewable resources are a strategic measure to make up for the shortage of resources in our country. As a measure to save resources and protect the environment, the recycling of waste plastics has been paid more and more attention. Due to the complexity of...
Examples
Embodiment 1
[0036] (a) Use an electronic balance to weigh 0.2±0.001g of the plastic sample, cut it into particles no larger than 0.2g, and put it into a 100ml beaker;
[0037] (b) Add 5 ml of sulfuric acid (H 2 SO 4 ), covered with a glass watch glass, placed on a heating plate with a temperature above 280°C, and heated for 20-30 minutes to decompose and carbonize the organic components; slowly add 5ml of nitric acid to the beaker to digest and oxidize the sample (repeat this step until sample is completely digested), Note meaning: Risk of splashing due to violent reaction;
[0038] (c) Remove the beaker from the heating plate, let it stand for cooling, then slowly add 10ml of perhydrochloric acid and 10ml of EDTA-2Na solution, heat the beaker on the heating plate, continue to heat until boiling, keep for 3 minutes, remove the beaker from the heating plate , leave to cool for 10 minutes (to room temperature);
[0039] (d) Rinse the beaker and glass watch glass used for pretreatment ...