Chamber Testing of Adsorption of Volatile Organic Compounds (VOCs) on Material Surfaces

Abstract

A simple test chamber method to quantify adsorption and desorption of organic compounds on material surfaces is described. Important environmental parameters such as temperature, relative humidity and air velocity were varied and controlled independently around typical indoor values. Experiments were performed with alpha-pinene and toluene in concentrations of 160-300 micrograms/m3. The measurements show adsorption on and desorption from wool carpet, nylon carpet, polyvinyl chloride (PVC) floor coverings, cotton curtain material and the empty chamber. The ranking of the materials, with respect to their sorption capacity, is as mentioned above. The adsorption of alpha-pinene was higher than the adsorption of toluene for all the materials. Air velocity was not found to influence the sorption of alpha-pinene and toluene on wool carpet, tested with air velocities at 0, 10 and 20 cm/s. The experiments were carried out during both the adsorption and the desorption phase. The uncertainty of the experiments was lowest during the desorption phase. Based on the results obtained, it can be recommended that sorption experiments should be performed as desorption phase experiments. A one-sink model, based on the Langmuir adsorption isotherm, appears adequate to describe the results.

Surface analysis of particulates from laboratory hood exhaust manifold

“…32 On the other hand, the slow rate of depletion was surprising, given the very high flow velocity in the exhaust manifold. However, the results are in qualitative accord with the findings of Jorgensen, who concluded that flow rate was not an important influence on sorption processes of organics in test chamber experiments, 2 and with the fact that sorption would be the rate limiting process in depletion. Certainly the depletion function would be expected to be more complex than a single exponential because of the varied nature of the surfaces in the hood ventilation system.…”

“…At higher masses, cluster ions containing CHA were also observed, which provided additional insight into the chemical nature of the surface. The most abundant of the cluster ions corresponded to [((CHA)H) 2 …”

Emission Rates of Volatile Organic Compounds Released from Newly Produced Household Furniture Products Using a Large-Scale Chamber Testing Method

“…Among the VOCs detected, toluene and α -pinene from a sofa sample recorded the largest mean equilibrium concentrations (353 and 189  μ g/m 3 , resp.). Reference [33] used the toluene and α -pinene to evaluate VOC emission rates from a number of potential sources, including wool carpet, nylon carpet, and cotton curtain. These authors conducted two types of experiments to induce both adsorption (in which toluene and α -pinene were introduced into the chamber) and desorption (in which only clean air was brought in).…”

Determination of emission characteristics of volatile compounds from mosquito repellents (MRs) by headspace and chamber methods, and indoor levels related to use of MRs

“…However, in actual apartment bedrooms, VOCs emitted from MRs can be adsorbed onto the surface of furniture such as beds and closets. In addition, building International Journal of Environmental Analytical Chemistry 1135 finishing materials such as walls, floors and ceilings can also adsorb VOCs [24][25][26]. Indoor chemistry would be insignificant as regards the discrepancy of measured and estimated data for BTEX, since these compounds are inert [27].…”