Volhard titration.  After this it is 'ion chromatography' a form of HPLC.

Hi you can remove most of the organic compound through charring and ashing process in a muffled furnace. 

Dissolve your residue in water, filter and top up to a known volume. Your sample is ready for chloride analysis. 

Choices of analysis : Mohr Titration , Volhard Titration (mentioned by Mr. Bruce), Ion Chromatography , Ion Selective Electrode etc 

If you are expecting trace level of chloride in your sample, most suitable method is Ion Chromatography.

Simplest method would be Mohr and Volhard Titration method.  

Hope this helps. 

thks everyone. Yan Jie I'll try your method

Dear Yan Jie

can i an idea of the amount of chloride in sugar factory scum/filter cake.

thanks

Sorry to disappoint you but I really have no idea the range because it is a very common element.

It very depends on the factory process, material etc. Two different factories in same industry might differ a lot on their filter cake quality.

If you want to estimate range of chloride in your sample, maybe you can try follow steps: 

1) Prepare known concentration of chloride solution (~1000mg/L) using NaCl 

2) Pipette 5 - 10ml of the solution into a test tube

3) Add 1ml 0.1M silver nitrate solution

4) Char, ash, dissolve and filter 10g of your sample into a 50ml volumetric flask, top up with distilled water

5) Take 5 - 10ml of your sample solution (exactly same amount as your standard)

6) Add 1ml 0.1M silver nitrate solution

7) Observe turbidity of the solution

If your sample solution was saturated with white precipitate, lower down sample size taken (50ml) before you proceed to titration method (save your titrant cost) 

If your sample solution has slightly higher or same turbidity compared to your standard solution, you can try titration method with equivalent or higher concentration of titrant.

If your sample solution has lower turbidity than your standard solution, you can try titration using lower concentration of titrant and must include a method blank.

If your sample solution didn't show significant turbidity, you can try ion chromatography or ion selective electrode method.