Unfortunately, that is not possible. The 32K RAM is first supported by S110 7.1.0, see the S110 release notes
Update 21.9.2015
Softdevice S110 v7.0.0 was the first softdevice to be tested with third revision nRF51. For first and second revision nRF51, all nRF51 chip variants had 16kB RAM. There was however a bug in S110 7.0.0 that it only supported 16kB RAM and therefore the remaining 16kB of the RAM in the nRF51822/nRF51422 QFAC variant could not be utilized. This was fixed for S110 v7.1.0 which is reported in the release notes for S110 v7.1.0 in the "Bug fixes" section:
Fixed an issue, effecting nRF51 chips with more than 16 kB of RAM, that could cause an assert at sd_ble_enable() or cause SVC calls to return NRF_ERROR_INVALID_ADDRESS when a pointer to RAM above 16 kB was supplied
Unfortunately, that is not possible. The 32K RAM is first supported by S110 7.1.0, see the S110 release notes
Update 21.9.2015
Softdevice S110 v7.0.0 was the first softdevice to be tested with third revision nRF51. For first and second revision nRF51, all nRF51 chip variants had 16kB RAM. There was however a bug in S110 7.0.0 that it only supported 16kB RAM and therefore the remaining 16kB of the RAM in the nRF51822/nRF51422 QFAC variant could not be utilized. This was fixed for S110 v7.1.0 which is reported in the release notes for S110 v7.1.0 in the "Bug fixes" section:
Fixed an issue, effecting nRF51 chips with more than 16 kB of RAM, that could cause an assert at sd_ble_enable() or cause SVC calls to return NRF_ERROR_INVALID_ADDRESS when a pointer to RAM above 16 kB was supplied
