From: "jhannapel@thepolicygroup.com" <jhannapel@thepolicygroup.com>

To: Phil Mulrine/RTP/USEPA/US@EPA, Steve Fruh/RTP/USEPA/US@EPA, Chuck 

French/RTP/USEPA/US@EPA

Cc: <crichter@thepolicygroup.com>

Date: 07/11/2012 03:33 PM

Subject: Chromium Emissions Study with Fume Suppressants

Steve, Chuck and Phil, 

Attached is a PowerPoint presentation summarizing a German study on chromium emissions from 

experimental baths using different fume suppressants, including PFOS and two different non-PFOS 

alternatives. The results demonstrate that although the surface tension was maintained at 30 dynes, the 

chromium emissions were different for each. The PFOS reduced chromium emissions significantly (with 

the presences of a small foam blanket), one non-PFOS alternative reduced chromium emissions 

significantly, but not as well as PFOS (with a very heavy foam blanket), and one non-PFOS alternative 

had chromium emissions that were greater that the control that had no fume suppressants (no foam was 

generated with this fume suppressant). The chromium emissions for the PFOS and the first non-PFOS 

that controlled emissions were below the German air emissions standard, but not necessarily below 

EPA's proposed emission limits for chromium electroplating and anodizing baths. Based on these results, 

it would appear that more study is required, particularly with respect to the use of non-PFOS fume 

suppressants, before EPA can support any new emission limits. 

The reuslts of this study are consistent with the position that we have presented to you from the beginning 

that the proposed emissions limits cannot be achieved with the use of fume suppressants, especially with 

non-PFOS alternatives -- which will soon be the only technology available due to EPA's Voluntary 

Stewardship Program to elimiante PFOS and the TSCA Action Plan to ban the use of PFOS and other 

long-chain PFCs. In the absence of specific data that shows the use of non-PFOS fume suppressants 

can achieve the proposed limits, it is not clear how the proposed emission limits can be supported by any 

credible scientific data.

We are expecting the formal study from Germany, but it is in the process of being translated into English. 

As soon as we receive the final study in English, we will forward it to you. We would be happy to discuss 

the results of this study and look forward to working with you on a reasonable outcome for this 

rulemaking. Please contact Christian Richter or me to discuss this further.

Best regards,

Jeff (See attached file: Chrome MACT EMD Cr Emissions Presn USEPA July 11.xps)
Effect on Cr(VI) Emissions and 

Surface Tension of Non-PFOS 

Mist Suppressants in Hard and 

Decorative Chrome Plating

MERCK KGaA, Darmstadt, Germany

EMD
Agenda

 New Merck/EMD non-PFOS fume suppressant Cr(VI) emissions study

background

 New Merck/EMD non-PFOS product- attributes

 Cr(VI) emissions study experimental conditions

2 Cr(VI) Emissions | 11 August 2012

 Cr(VI) emissions study experimental conditions

 Cr(VI) emissions results for „hard chrome“ 

 Cr(VI) emissions results for „decorative chrome“ 

 Study conclusions

 Discussion
New Merck/EMD Non-PFOS Fume Suppressant

Cr(VI) Emissions Background

 Merck/EMD study was conducted at a German Institute (IGOS)

– Specialized chromium plating experience

 Study involved Merck/EMD new product , MAFS-010 (Tivida FL2100TM), alternative 2100TM), alternative commercial commercial non-PFOS product product and PFOS

 Study measured Cr(VI) emissions using EPA recommended methods

 Study was done using 4.5 L glass vessels

 Study measured surface tension using tensiometer

 Study was run using „typical“ concentrations for chromium plating

 Cr(VI) emissions results measured before any scrubbing

3 Cr(VI) Emissions | 11 August 2012
New Merck/EMD Non-PFOS Product –

Attributes

• Chemistry

– Merck/EMD mist suppressant is a perfluorinated phosphinic acid

– Merck/EMD process is patented by Merck

• Regulatory Status

– Merck/EMD product is currently available under USEPA LVE 

– Merck/EMD product cleared under REACH up to 10 tons active

• Market Situation

– Merck/EMD product successfully „beta tested“ by large US fume

suppressant suppliers

– No commercial sales in USA or EU to date

4 Cr(VI) Emissions | 11 August 2012
New Merck/EMD Non-PFOS Product –

Attributes

Performance

– Durable surface tension reduction

– No foam

– „Concentrates“ in plating plant sludge with precipitation by lime

milk

– Does not bioaccumulate

– Good aquatic toxicity characteristics

5 Cr(VI) Emissions | 11 August 2012
New Merck/EMD Non-PFOS Product Surface 

Tension Measurements in H2O

Results:

 MAFS-010 shows

typical surfactant 

property in H2O

MAFS-010 γ/concentration in H2O

6

property in H2O

Cr(VI) Emissions | 11 August 2012
New Merck/EMD Product Surface Tension 

Measurements In Chromium Electrolytes

Results:

 With 200 ppm the 

surface tension is

lowered to 32 mN/m

MAFS-010 γ/concentration curve in electrolyte for hard chrome plating

7

 A reduction 

γ< 25mN/m is 

possible with a 

higher amount of 

MAFS-010

Cr(VI) Emissions | 11 August 2012
Chromium Emissions Study Tank Conditions

For Hard and Decorative Chrome Plating

 Study was performed in 4.5 L glass vessels

 Off-gases collected using PVC pipe collector surrounding the vessels

– PVC pipe had holes drilled regularly around the inside perimeter

 Temperatures Temperatures held between between 55 and 60 deg C

 Metal concentrations identical for hard and decorative baths

 Current density much higher for hard chrome tests

 Details of bath contents and conditions on next slide

8 Cr(VI) Emissions | 11 August 2012
New Merck/EMD Product Cr(VI) Emissions for 

Hard Chrome And Decorative Chrome Plating:

Experimental Conditions

Parameter hard chrome plating

decorative chrome 

plating

chromium trioxide 260 g/l 260 g/l 

chromium(III) ca. 3 g/l ca. 3 g/l 

9

sulfate ca. 3 g/l ca. 3 g/l

electrolyte volume 4,5 l 4,5 l

temperature 55-60 °C 55-60 °C

current density 50 A/dm2 20 A/dm2

Difference in decorative

plating is lower current density

Cr(VI) Emissions | 11 August 2012
New Merck/EMD Product – Cr(VI) Emissions

Results For Hard Chrome

 PFOS, non-PFOS commercial alternative, and MAFS-010 (Tivida FL-2100TM) were

tested

 Initial surface tensions of approximately 30 dynes for all three baths (tensiometer)

 PFOS vessel covered with foam in thin layer

 Non-PFOS alternative vessel completely covered with foam in very thick layer

 MAFS-010 product vessel shows no foam

– Shown in picture on next slide

 Cr(VI) emissions measured in PVC pipe before any scrubbing

– It should be noted that European chromium plating is regulated by Cr(VI) emissions

ONLY, not surface tensions

– German limit is shown on next slide

 Cr(VI) data results shown on next slide

10 Cr(VI) Emissions | 11 August 2012
New Merck/EMD Product Hard Chrome Plating 

Results

11

Conclusions for hard chrome plating:

 MAFS-010 causes an increase of the chromium emission (possible explanation by IGOS: 

stabilization of aerosols by MAFS-010)

 PFOS and Non-PFOS Alternative perform below EU legal limits of 50 μg/m3 

MAFS-010 Non-PFOS

Alternative

PFOS

Cr(VI) Emissions | 11 August 2012
New Merck/EMD Product - Cr(VI) Emissions

Results For Decorative Plating

 Decorative chromium plating conditions run according to earlier slide

– Identical bath composition to hard chrome

– Much lower current density

 All vessels run at approximately 30 dynes surface tension (tensiometer)

 Same off-gas collection system and analytical protocols

 MAFS-010 (Tivida FL-2100TM) , non-PFOS alternative and „no mist suppressant“ tested

 Due to changes in air flow, decorative Cr(VI) emissions results should not be compared

to hard chrome results

 Cr(VI) emissions for decorative plating as shown on next slide

12 Cr(VI) Emissions | 11 August 2012
Decorative chrome plating results

Design of experiment

 No Cr(VI)- emission of the chromium bath 

without electric current 

 Cr (VI) emission is not caused by 

contaminations in the tubes

 Decorative experiments were done with two 

cells (instead of three like in hard chrome) 

 air flow and the resulting Cr (VI)-

13

emission of the cells is not comparable to 

the hard chrome experiments 

Conclusions for decorative chrome plating:

 MAFS-010 causes a chromium emission which is significantly higher than the Non-PFOS 

alternative (H4PFOS)

 Non-PFOS alternative (H4PFOS) performs below EU legal limits of 50 μg/m3

Cr(VI) Emissions | 11 August 2012
Conclusions

 Cr(VI) emission results with Tivida FL-2100TM (MAFS-010), at an approximate 

surface tension of 30 dynes, are much higher than the legal limits of 50 μg/m3

under both hard and decorative chrome conditions

 A competitive commercial non-PFOS alternative, at an approximate surface 

tension of 30 dynes, controls the Cr(VI) emissions below the EU limits

 The traditional relationship between bath surface tension and the resulting 

Cr(VI) emissions must be called into question. 

 This relationship was found not to be valid for MAFS-010 (Tivida FL-2100TM)

 The cause(s) of the higher Cr(VI) emissions for MAFS-010 (Tivida FLTM) are 

not known 

14 Cr(VI) Emissions | 11 August 2012
Regulatory limits for Cr (VI) emission for 

chromium plating

Legal limits USA

(National Emissions Standards for 

Hazardous Air Pollutants (NESHAPs) 

set by the United States EPA [15]; 2002)

Emmision Concentration= 0,015mg/m3

γ= 45mN/m (stalagmometer)

γ= 35mN/m (Tensiometer)

The proposed amendments to the NESHAP addressed

Legal limits Germany

(TA Luft 2002 [14])

Mass Flow = 0,15g/h

Mass Conc. = 0,05mg/m3

The maximum allowable mass

emission rate calculated using equation [15]:

MAMER = ETSA × K × 0.015 mg/dscm

15

The proposed amendments to the NESHAP addressed

five technical areas: 

(1) The use of fume suppressants for controlling chromium

emissions from hard chromium electroplating tanks

(2) a revised surface tension limit for decorative chromium 

electroplating tanks when measuring surface tension with a 

tensiometer

(3) an alternate emission limit for hard chromium electroplating

tanks equipped with enclosing hoods

(4) revised definitions for chromium electroplating and chromium 

Anodizing tanks

(5) the pressure drop monitoring requirement for composite

mesh pad (CMP) control systems.

MAMER = the alternative emission rate for enclosed hard chromium

electroplating tanks in mg/hr

ETSA = the hard chromium electroplating tank surface area in

square feet(ft 2).

K = a conversion factor, 425 dscm/(ft2× hr)

Analytical procedure for chromium 

emission concentration (Method 306):

inductively-coupled plasma emission spectrometry (ICP)

graphite furnace atomic absorption spectrometry (GFAAS)

ion chromatography with a postcolumn

reactor (IC/PCR)

(Details see [20; S2146])

Cr(VI) Emissions | 11 August 2012