Fully automatic determination of organic additives in electroplating baths with CVS Voltammetry The 838 Advanced VA Sample Suppressor determination Processor in a nutshell The new 838 Advanced VA Sample Processor allows Suppressors and similar compounds are determined the fully automatic and extremely flexible processing of by Dilution Titration in combination with the CVS tech-large sample series in the routine monitoring of electro-nique. Using an 800 Dosino, the calibration standard so-plating baths. lutions or bath samples are taken from the sample ves-This means that the 838 Advanced VA Sample Pro-sels on the rack of the Advanced VA Sample Processor cessor is the ideal partner for the 797 VA Computrace and added in small steps to the Virgin Makeup Solution for the fully automated determination of organic addi- (VMS) in the measuring vessel. The VMS is added by a tives in electroplating baths by means of the CVS tech-second 800 Dosino. nique (Cyclic Voltammetric Stripping). Both Dilution Ti-Placing both samples and calibration standards on the tration (DT) for the determination of suppressors (level-sample processor makes it possible to automatically ers, carriers) and LAT (Linear Approximation Technique) calibrate methods before and even during a sample se-or MLAT (Modified Linear Approximation Technique) for ries. A maximum of 56 samples or calibration standard the determination of brighteners can be automated. solutions can be analyzed in a single run. The large sample rack of the 838 Advanced VA Sample Between the determinations the measuring vessel is au-Processor with 112 positions for different vessel sizes tomatically emptied and thoroughly rinsed with water guarantees the rapid and efficient determination of addi-using two 823 Membrane Pump Units. Carryover is thus tives – even with large sample numbers. reliably prevented. The CVS technique is used, for example, for monitoring the following types of electroplating baths: • Acidic copper baths • Tin baths • Tin-lead baths • Alkaline zinc baths Existing, manually operated 797 VA Computrace systems can, of course, be easily extended with the 838 Advanced VA Sample Processor. Completely automated analysis system for the determination of suppressors, consisting of 797 VA Computrace, 838 Advanced VA Sample Processor, two 800 Dosinos and rinsing equipment. 838 Advanced VA Sample Processor Voltammetry Brightener determination Advantageous flexibility Brighteners in electroplating baths are determined by For convenient instrument configuration the 838 Ad-the two related calibration techniques LAT (Linear Ap-vanced VA Sample Processor has a separate keypad proximation Technique) or MLAT (Modified Linear Ap-with LCD display. With the method editor, the prepro-proximation Technique) in combination with the mea-grammed methods can be very easily adapted to your suring techniques CVS (Cyclic Voltammetric Stripping) individual requirements. or CPVS (Cyclic Pulse Voltammetric Stripping). All these The sample rack accommodates a maximum of 56 sam-techniques are supported by the 797 VA Computrace ple vessels with a capacity of 5 to 11 mL as well as a fur-and can be automated with the 838 Advanced VA Sam-ther 56 sample vessels with a capacity of 20 to 50 mL. ple Processor. This means that sample volumes in the range between 5 In brightener determination by the MLAT calibration and 50 mL can be processed without any problems. technique, the so-called intercept solution and the stan-The automated analytical procedure is completely con-dard brightener solution are dosed into the measur-trolled by the software of the 797 VA Computrace. This ing vessel using 800 Dosinos. After the determination includes both the control of the 838 Advanced VA Sam-of the intercept value the bath sample is transferred to ple Processor and the 800 Dosinos connected to the the measuring vessel by means of the peristaltic pump 797 VA Computrace. built into the 838 Advanced VA Sample Processor and added to the intercept solution. In the LAT calibration technique both the intercept solution and the bath samples are transferred into the measuring vessel by means of the peristaltic pump built into the 838 Advanced VA Sample Processor. The solution transfer permits a real, fully automatic MLAT determination without having to remove the elec-trodes from the solution during the measurement. This guarantees the highest possible reproducibility and ac-curacy of the results. The brightener content of up to 28 samples can be analyzed automatically in a single run. As in the suppressor determination, the measuring vessel is automatically emptied and rinsed after each determination. All the waste is collected centrally in a waste container, which allows the analysis system to be operated easily and cleanly. Completely automated analysis system for the determination of brighteners, consisting of 797 VA Computrace, 838 Advanced VA Sample Processor, three 800 Dosinos and rinsing equipment. 838 Advanced VA Sample Processor Voltammetry Specifications Ordering information Capacity 56 positions for sample ves- 2.838.0310 838 Advanced VA Sample Processor sels with max. 11 mL solu-Sample Changer for the fully automat-tion ic determination of organic additives in 56 positions for sample ves-electroplating baths by means of CVS sels with max. 50 mL solu- in combination with the 797 VA Com-tion putrace. Capacity: max. 56 solutions Sample volume 5…50 mL of 5 to 11 mL volume and 56 solutions of 20 to 50 mL. With built-in peri-Operation Via external keypad staltic pump for sample transfer. Flex-Peristaltic pump Dual-channel pump ible method setup and parameter settings via the included keypad. Includes Rotation rate ±6.7…±100 min–1 comprehensive accessories for setting (adjustable in 15 steps) up the measuring station: sample rack, Flow rate Typically 3.8 mL/min keypad, tubings, sample vessels and (with 6.1826.020 tubing and splash protection. Without connecting 20 min–1) cable and without rinsing equipment. Typically 25 mL/min (with 6.1826.150 tubing and Consumables 67 min–1) 6.2743.057 Sample vessel 11 mL made of polypro-The flow rate depends on the pylene (200 pieces) mechanical tension applied 6.2747.010 Sample vessel 50 mL made of polypro-to the tubing and has been pylene (25 pieces) measured with water and in the absence of any counter- 6.1826.020 Pump tubing for a typical flow rate of pressure approx. 3.8 mL/min Pressure Max. 0.4 MPa (4 bar) 6.1826.150 Pump tubing for a typical flow rate of approx. 25 mL/min Dimensions Width 280 mm Height 730 mm Depth 500 mm Equipment for rinsing and emptying the measuring vessel on the 797 VA Computrace 2.731.0010 731 Relay Box 2 x 2.823.0010 823 Membrane Pump Unit 2 x 6.2160.010 Adapter cable 6.5323.010 Rinsing equipment for VA instrument with connected Membrane Pump Units 6.2141.180 Connecting cable 797 VA Computrace – 838 Advanced VA Sample Processor Subject to modifications – Printed in Switzerland by Metrohm Ltd., CH-9101 Herisau – 8.838.6013 – 2004-12 838 Advanced VA Sample Processor